diff --git a/config.example.toml b/config.example.toml
index 03e56bdf..fde5d9c1 100644
--- a/config.example.toml
+++ b/config.example.toml
@@ -915,6 +915,57 @@ default_text_model = "deepseek-ai/deepseek-v4-pro"
 # printf '%s\n' '{"content":"audit wrapper placeholder: configure an executor","success":false}'
 # ```
 
+# ─────────────────────────────────────────────────────────────────────────────────
+# Agent Fleet trust, security, and role registry (#3165, #3167)
+# ─────────────────────────────────────────────────────────────────────────────────
+# [fleet]
+# # Default trust level for fleet workers: "sandbox" | "local" | "remote-verified" | "operator"
+# default_trust_level = "sandbox"
+# # Require SSH host-key verification before granting remote-verified trust
+# require_identity_verification = true
+# # Maximum trust level any worker may have
+# max_trust_level = "operator"
+#
+# # Headless worker execution hardening (#3027)
+# [fleet.exec]
+# # Tools always allowed regardless of role
+# allowed_tools = []
+# # Tools always disallowed (overrides role and task spec)
+# disallowed_tools = ["exec_shell"]
+# # Hard ceiling on worker steps (tool calls + model turns)
+# max_turns = 500
+# # Recursive child-agent depth for fleet workers. Shares ONE recursion axis
+# # with standalone sub-agents (a fleet worker IS a headless sub-agent).
+# # 0 blocks child agents (the root worker still runs); 3 is the default and the
+# # cap, affording at least three nested delegation levels.
+# max_spawn_depth = 3
+# # Extra system prompt injected into every headless worker
+# append_system_prompt = "Never modify .git/config or change remotes."
+# # Output format: "text" (default) or "stream-json" for ndjson events
+# output_format = "text"
+#
+# # Built-in role presets are always available: smoke-runner, reviewer, builder, read-only.
+# # User-defined roles here override or extend the built-in set. Any key under
+# # [fleet.roles] becomes a valid role name that task specs can reference.
+# [fleet.roles.ci-linter]
+# description = "Runs linters and formatters"
+# tool_profile = "read-only"
+# tools = ["cargo", "cargo-clippy", "cargo-fmt"]
+# capabilities = ["rust"]
+# max_tokens = 12000
+# max_tool_calls = 20
+# timeout_seconds = 600
+#
+# [fleet.roles.pr-reviewer]
+# description = "Reviews PRs with GitHub access"
+# tool_profile = "read-only"
+# tools = ["git", "gh", "rg"]
+# capabilities = ["git", "github"]
+# max_tokens = 16000
+# max_tool_calls = 30
+# timeout_seconds = 900
+# trust_level = "local"
+
 # ─────────────────────────────────────────────────────────────────────────────────
 # Requirements (admin constraints) example file
 # ─────────────────────────────────────────────────────────────────────────────────
diff --git a/crates/cli/src/lib.rs b/crates/cli/src/lib.rs
index dcd149b2..fd0f7e8f 100644
--- a/crates/cli/src/lib.rs
+++ b/crates/cli/src/lib.rs
@@ -22,7 +22,7 @@ use codewhale_mcp::{McpServerDefinition, run_stdio_server};
 use codewhale_secrets::Secrets;
 use codewhale_state::{StateStore, ThreadListFilters};
 
-#[derive(Debug, Clone, Copy, ValueEnum)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, ValueEnum)]
 enum ProviderArg {
     Deepseek,
     NvidiaNim,
@@ -43,6 +43,10 @@ enum ProviderArg {
     Huggingface,
     Together,
     OpenaiCodex,
+    Anthropic,
+    Zai,
+    Stepfun,
+    Minimax,
 }
 
 impl From<ProviderArg> for ProviderKind {
@@ -67,6 +71,10 @@ impl From<ProviderArg> for ProviderKind {
             ProviderArg::Huggingface => ProviderKind::Huggingface,
             ProviderArg::Together => ProviderKind::Together,
             ProviderArg::OpenaiCodex => ProviderKind::OpenaiCodex,
+            ProviderArg::Anthropic => ProviderKind::Anthropic,
+            ProviderArg::Zai => ProviderKind::Zai,
+            ProviderArg::Stepfun => ProviderKind::Stepfun,
+            ProviderArg::Minimax => ProviderKind::Minimax,
         }
     }
 }
@@ -787,7 +795,7 @@ fn provider_slot(provider: ProviderKind) -> &'static str {
 }
 
 /// Provider order used by the `auth list` and `auth status` outputs.
-const PROVIDER_LIST: [ProviderKind; 20] = [
+const PROVIDER_LIST: [ProviderKind; 24] = [
     ProviderKind::Deepseek,
     ProviderKind::NvidiaNim,
     ProviderKind::Openai,
@@ -808,6 +816,10 @@ const PROVIDER_LIST: [ProviderKind; 20] = [
     ProviderKind::Huggingface,
     ProviderKind::Together,
     ProviderKind::OpenaiCodex,
+    ProviderKind::Anthropic,
+    ProviderKind::Zai,
+    ProviderKind::Stepfun,
+    ProviderKind::Minimax,
 ];
 
 fn provider_is_supported_by_tui(provider: ProviderKind) -> bool {
@@ -833,6 +845,10 @@ fn provider_is_supported_by_tui(provider: ProviderKind) -> bool {
             | ProviderKind::Huggingface
             | ProviderKind::Together
             | ProviderKind::OpenaiCodex
+            | ProviderKind::Anthropic
+            | ProviderKind::Zai
+            | ProviderKind::Stepfun
+            | ProviderKind::Minimax
     )
 }
 
@@ -2606,6 +2622,32 @@ mod tests {
             }))
         ));
 
+        for (provider, expected) in [
+            ("anthropic", ProviderArg::Anthropic),
+            ("zai", ProviderArg::Zai),
+            ("stepfun", ProviderArg::Stepfun),
+            ("minimax", ProviderArg::Minimax),
+        ] {
+            let cli = parse_ok(&[
+                "deepseek",
+                "auth",
+                "set",
+                "--provider",
+                provider,
+                "--api-key-stdin",
+            ]);
+            assert!(matches!(
+                cli.command,
+                Some(Commands::Auth(AuthArgs {
+                    command: AuthCommand::Set {
+                        provider,
+                        api_key: None,
+                        api_key_stdin: true,
+                    }
+                })) if provider == expected
+            ));
+        }
+
         let cli = parse_ok(&["deepseek", "auth", "list"]);
         assert!(matches!(
             cli.command,
diff --git a/crates/config/src/lib.rs b/crates/config/src/lib.rs
index 19ad3698..4adb69d7 100644
--- a/crates/config/src/lib.rs
+++ b/crates/config/src/lib.rs
@@ -659,6 +659,10 @@ pub struct ConfigToml {
     /// lifecycle `[hooks]` table so config rewrites preserve existing hooks.
     #[serde(default)]
     pub hook_sinks: Option<HookSinksToml>,
+    /// Agent Fleet trust and security policy (#3165). When absent, fleet
+    /// workers inherit conservative Sandbox defaults.
+    #[serde(default)]
+    pub fleet: Option<FleetConfigToml>,
     #[serde(flatten)]
     pub extras: BTreeMap<String, toml::Value>,
 }
@@ -1055,6 +1059,236 @@ impl Default for SnapshotsToml {
     }
 }
 
+/// On-disk schema for the `[fleet]` table (#3165). See `config.example.toml`
+/// and `docs/FLEET.md` for documentation.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct FleetConfigToml {
+    /// Default trust level for fleet workers. One of `"sandbox"`, `"local"`,
+    /// `"remote-verified"`, or `"operator"`. Defaults to `"sandbox"`.
+    #[serde(default = "default_fleet_trust_level_str")]
+    pub default_trust_level: String,
+    /// Require identity verification for remote (SSH) workers before
+    /// granting them `remote-verified` trust. Defaults to true.
+    #[serde(default = "default_fleet_require_identity")]
+    pub require_identity_verification: bool,
+    /// Maximum trust level any worker may have (`"sandbox"`, `"local"`,
+    /// `"remote-verified"`, or `"operator"`). Defaults to `"operator"`.
+    #[serde(default = "default_fleet_max_trust_level_str")]
+    pub max_trust_level: String,
+    /// User-defined and built-in role presets.
+    ///
+    /// Each role defines default tool profiles, capabilities, budgets, and
+    /// trust settings that task specs can reference by name. Built-in roles
+    /// (`smoke-runner`, `reviewer`, `builder`, `read-only`) are always
+    /// available; user-defined roles in config override or extend them.
+    #[serde(default)]
+    pub roles: BTreeMap<String, FleetRolePreset>,
+    /// Headless worker execution hardening (#3027).
+    #[serde(default)]
+    pub exec: FleetExecConfig,
+}
+
+/// Canonical recursion-depth policy for the headless worker runtime.
+///
+/// Single source of truth shared by BOTH standalone sub-agents and fleet
+/// workers so the two cannot drift into "two moving targets":
+/// - [`DEFAULT_SPAWN_DEPTH`] is the default recursion budget (the sub-agent
+///   runtime's `DEFAULT_MAX_SPAWN_DEPTH` is defined as this value).
+/// - [`MAX_SPAWN_DEPTH_CEILING`] is the hard safety cap; every configured
+///   value (fleet `max_spawn_depth`, `agent_open`'s `max_depth`) clamps to it.
+///
+/// A worker runs at `spawn_depth = 0` and may spawn while
+/// `spawn_depth + 1 <= max_spawn_depth`, so a depth of N affords N nested
+/// delegation levels below the root worker. The default of 3 affords at least
+/// three recursion levels out of the box; the root worker still runs at
+/// depth 0 even when the budget is 0.
+pub const DEFAULT_SPAWN_DEPTH: u32 = 3;
+
+/// Hard ceiling on recursion depth for any worker/sub-agent. See
+/// [`DEFAULT_SPAWN_DEPTH`]. Raising this single constant lifts the limit
+/// everywhere (the fleet clamp and `agent_open` validation both read it).
+pub const MAX_SPAWN_DEPTH_CEILING: u32 = 3;
+
+/// Headless worker execution constraints (#3027).
+///
+/// These limits apply to all fleet workers and sub-agents spawned through
+/// the headless worker runtime. Task specs can tighten but not loosen them.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct FleetExecConfig {
+    /// Tools that are always allowed regardless of role or task spec.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub allowed_tools: Vec<String>,
+    /// Tools that are always disallowed, overriding role and task spec.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub disallowed_tools: Vec<String>,
+    /// Hard ceiling on sub-agent steps (tool calls + model turns).
+    /// Workers that exceed this are terminated. Default: unbounded (u32::MAX).
+    #[serde(default = "default_fleet_max_turns")]
+    pub max_turns: u32,
+    /// Recursive child-agent budget for headless fleet workers.
+    /// Defaults to [`DEFAULT_SPAWN_DEPTH`] (3) so a fleet worker has the SAME
+    /// recursion budget as a standalone sub-agent — fleet and sub-agents are one
+    /// substrate, not two. Set 0 to block child `agent_open` (the root worker
+    /// still runs); the value is clamped to [`MAX_SPAWN_DEPTH_CEILING`].
+    #[serde(default = "default_fleet_max_spawn_depth")]
+    pub max_spawn_depth: u32,
+    /// Extra system prompt text appended to every headless worker.
+    /// Useful for injecting org-wide policy or behavior constraints.
+    #[serde(default, skip_serializing_if = "String::is_empty")]
+    pub append_system_prompt: String,
+    /// Output format for fleet worker results.
+    /// `"text"` (default) or `"stream-json"` for newline-delimited JSON events.
+    #[serde(default = "default_fleet_output_format")]
+    pub output_format: String,
+}
+
+fn default_fleet_max_turns() -> u32 {
+    u32::MAX
+}
+
+fn default_fleet_max_spawn_depth() -> u32 {
+    DEFAULT_SPAWN_DEPTH
+}
+
+fn default_fleet_output_format() -> String {
+    "text".to_string()
+}
+
+impl Default for FleetExecConfig {
+    fn default() -> Self {
+        Self {
+            allowed_tools: Vec::new(),
+            disallowed_tools: Vec::new(),
+            max_turns: default_fleet_max_turns(),
+            max_spawn_depth: default_fleet_max_spawn_depth(),
+            append_system_prompt: String::new(),
+            output_format: default_fleet_output_format(),
+        }
+    }
+}
+
+/// A named role preset that bundles common worker settings.
+///
+/// Task specs reference a role name (e.g. `"role": "reviewer"`), and the
+/// fleet manager fills in any missing fields from the preset. User-defined
+/// roles in `[fleet.roles]` override built-in defaults with the same name.
+///
+/// Token budgets and tool-call limits are task-level decisions — they don't
+/// belong on role presets. Use `timeout_seconds` as the safety bound.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct FleetRolePreset {
+    /// Short description of what this role is for.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub description: Option<String>,
+    /// Default tool profile (`"read-only"`, `"read-write"`, or `"custom"`).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub tool_profile: Option<String>,
+    /// Default set of tool names available to this role.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub tools: Vec<String>,
+    /// Default capability tags (e.g. `"rust"`, `"git"`, `"gh"`).
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub capabilities: Vec<String>,
+    /// Default timeout in seconds for tasks using this role.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub timeout_seconds: Option<u64>,
+    /// Default trust level override for this role.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub trust_level: Option<String>,
+}
+
+fn default_fleet_trust_level_str() -> String {
+    "sandbox".to_string()
+}
+
+fn default_fleet_require_identity() -> bool {
+    true
+}
+
+fn default_fleet_max_trust_level_str() -> String {
+    "operator".to_string()
+}
+
+impl Default for FleetConfigToml {
+    fn default() -> Self {
+        Self {
+            default_trust_level: default_fleet_trust_level_str(),
+            require_identity_verification: default_fleet_require_identity(),
+            max_trust_level: default_fleet_max_trust_level_str(),
+            roles: BTreeMap::new(),
+            exec: FleetExecConfig::default(),
+        }
+    }
+}
+
+impl FleetConfigToml {
+    /// Resolve a role preset by name. Checks user-defined roles first,
+    /// then falls back to built-in role defaults.
+    #[must_use]
+    pub fn resolve_role(&self, name: &str) -> Option<FleetRolePreset> {
+        self.roles
+            .get(name)
+            .cloned()
+            .or_else(|| built_in_role_presets().get(name).cloned())
+    }
+}
+
+/// Built-in role presets that are always available without config.
+#[must_use]
+pub fn built_in_role_presets() -> BTreeMap<String, FleetRolePreset> {
+    [
+        (
+            "smoke-runner".to_string(),
+            FleetRolePreset {
+                description: Some("Lightweight read-only smoke check worker".to_string()),
+                tool_profile: Some("read-only".to_string()),
+                tools: vec![],
+                capabilities: vec![],
+                timeout_seconds: Some(300),
+                trust_level: Some("local".to_string()),
+            },
+        ),
+        (
+            "reviewer".to_string(),
+            FleetRolePreset {
+                description: Some("Read-only code and documentation review".to_string()),
+                tool_profile: Some("read-only".to_string()),
+                tools: vec![],
+                capabilities: vec![],
+                timeout_seconds: Some(600),
+                trust_level: None,
+            },
+        ),
+        (
+            "builder".to_string(),
+            FleetRolePreset {
+                description: Some(
+                    "Read-write builder with compilation and test access".to_string(),
+                ),
+                tool_profile: Some("read-write".to_string()),
+                tools: vec![],
+                capabilities: vec![],
+                timeout_seconds: Some(1800),
+                trust_level: Some("local".to_string()),
+            },
+        ),
+        (
+            "read-only".to_string(),
+            FleetRolePreset {
+                description: Some(
+                    "Minimal read-only observer with no writes or secrets".to_string(),
+                ),
+                tool_profile: Some("read-only".to_string()),
+                tools: vec![],
+                capabilities: vec![],
+                timeout_seconds: Some(300),
+                trust_level: Some("sandbox".to_string()),
+            },
+        ),
+    ]
+    .into()
+}
+
 /// On-disk schema for the `[network]` table (#135). See `config.example.toml`
 /// for documentation.
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -7128,6 +7362,32 @@ fallback_providers = ["deepseek", "openrouter"]
         assert!(!serialized.contains("fallback_providers"));
     }
 
+    #[test]
+    fn fleet_exec_config_default_matches_subagent_spawn_depth() {
+        // Fleet workers and standalone sub-agents share one recursion axis:
+        // the fleet default equals DEFAULT_SPAWN_DEPTH (3) and affords >=3
+        // nested delegation levels out of the box.
+        assert_eq!(
+            FleetExecConfig::default().max_spawn_depth,
+            DEFAULT_SPAWN_DEPTH
+        );
+        assert_eq!(FleetExecConfig::default().max_spawn_depth, 3);
+        assert!(DEFAULT_SPAWN_DEPTH <= MAX_SPAWN_DEPTH_CEILING);
+    }
+
+    #[test]
+    fn fleet_exec_config_parses_max_spawn_depth() {
+        let config: ConfigToml = toml::from_str(
+            r#"
+[fleet.exec]
+max_spawn_depth = 2
+"#,
+        )
+        .expect("fleet exec config should parse");
+
+        assert_eq!(config.fleet.expect("fleet config").exec.max_spawn_depth, 2);
+    }
+
     #[test]
     fn fallback_providers_do_not_change_runtime_resolution() {
         let _lock = env_lock();
diff --git a/crates/protocol/src/fleet.rs b/crates/protocol/src/fleet.rs
index 40deb957..11ef671e 100644
--- a/crates/protocol/src/fleet.rs
+++ b/crates/protocol/src/fleet.rs
@@ -12,7 +12,7 @@
 use std::collections::BTreeMap;
 use std::path::PathBuf;
 
-use serde::{Deserialize, Deserializer, Serialize, Serializer};
+use serde::{Deserialize, Deserializer, Serialize, Serializer, de};
 use serde_json::Value;
 
 pub const FLEET_PROTOCOL_VERSION: &str = "0.1.0";
@@ -45,6 +45,8 @@ pub struct FleetRun {
     pub worker_specs: Vec<FleetWorkerSpec>,
     #[serde(default)]
     pub labels: BTreeMap<String, String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub security_policy: Option<FleetSecurityPolicy>,
     pub created_at: String,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub updated_at: Option<String>,
@@ -260,6 +262,9 @@ pub struct FleetWorkerSpec {
     pub name: String,
     pub host: FleetHostSpec,
     #[serde(default)]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub trust_level: Option<FleetTrustLevel>,
+    #[serde(default)]
     pub labels: BTreeMap<String, String>,
     #[serde(default)]
     pub capabilities: Vec<String>,
@@ -280,6 +285,14 @@ pub enum FleetHostSpec {
         user: Option<String>,
         #[serde(skip_serializing_if = "Option::is_none")]
         identity: Option<PathBuf>,
+        /// Known hosts file for host-key verification.
+        #[serde(skip_serializing_if = "Option::is_none")]
+        known_hosts: Option<PathBuf>,
+        /// Expected host key fingerprint (SHA256:...) for key pinning.
+        /// When set, the connection is only trusted if the server's
+        /// host key matches this fingerprint exactly.
+        #[serde(skip_serializing_if = "Option::is_none")]
+        host_key_fingerprint: Option<String>,
         #[serde(skip_serializing_if = "Option::is_none")]
         working_directory: Option<PathBuf>,
         #[serde(default)]
@@ -288,6 +301,8 @@ pub enum FleetHostSpec {
         #[serde(skip_serializing_if = "Option::is_none")]
         codewhale_binary: Option<String>,
     },
+    #[serde(alias = "container")]
+    #[serde(alias = "Container")]
     Docker {
         image: String,
         #[serde(default)]
@@ -295,6 +310,264 @@ pub enum FleetHostSpec {
     },
 }
 
+// ── Security and trust types ────────────────────────────────────────────────
+
+/// Trust classification assigned to a worker host.
+///
+/// The trust level determines what a worker is allowed to do and what
+/// secrets it may access. The default for new workers is [`FleetTrustLevel::Sandbox`];
+/// operators must explicitly raise trust for SSH or container workers.
+#[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
+#[serde(rename_all = "snake_case")]
+pub enum FleetTrustLevel {
+    /// Fully isolated: no network, no secrets, no writes outside `.codewhale/fleet/`.
+    /// Suitable for untrusted code review, community PR checks, or third-party tool runs.
+    Sandbox = 0,
+    /// Local-only worker with access to the workspace and configured secrets.
+    /// Default for local workers. May read repo files but writes are gated.
+    Local = 1,
+    /// Worker on a known remote host with verified identity and a bounded
+    /// set of explicitly granted capabilities. Requires SSH host-key
+    /// verification or equivalent attestation.
+    #[serde(alias = "remote-verified", alias = "remoteVerified")]
+    RemoteVerified = 2,
+    /// Fully trusted worker (e.g. operator's own machine, CI runner).
+    /// Has access to all configured secrets and may perform any action the
+    /// operator can. Reserved for dogfood smoke and operator-owned machines.
+    Operator = 3,
+}
+
+impl Default for FleetTrustLevel {
+    fn default() -> Self {
+        Self::Sandbox
+    }
+}
+
+impl FleetTrustLevel {
+    /// Whether this trust level is allowed to access provider secrets.
+    #[must_use]
+    pub fn may_access_secrets(&self) -> bool {
+        matches!(self, Self::Operator | Self::RemoteVerified | Self::Local)
+    }
+
+    /// Whether this trust level is allowed to write outside `.codewhale/fleet/`.
+    #[must_use]
+    pub fn may_write_workspace(&self) -> bool {
+        matches!(self, Self::Operator | Self::Local)
+    }
+
+    /// Whether this trust level is allowed network access.
+    #[must_use]
+    pub fn may_access_network(&self) -> bool {
+        matches!(self, Self::Operator | Self::RemoteVerified | Self::Local)
+    }
+}
+
+/// Security policy applied to a fleet run.
+///
+/// A policy defines the default trust level for workers, which secrets
+/// may be resolved, and what capabilities are granted. When a run has no
+/// explicit policy, workers inherit conservative defaults.
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+pub struct FleetSecurityPolicy {
+    /// Default trust level for workers that don't declare one explicitly.
+    #[serde(default)]
+    pub default_trust_level: FleetTrustLevel,
+    /// Secret refs that workers may resolve. An empty list means no secrets
+    /// are available. Each entry is a key name, not a value.
+    #[serde(default)]
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    pub allowed_secrets: Vec<FleetSecretRef>,
+    /// Capability grants for workers in this run.
+    #[serde(default)]
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    pub capability_grants: Vec<FleetCapabilityGrant>,
+    /// Maximum trust level any worker in this run may have, even if the
+    /// worker spec requests higher. Defaults to Operator (no ceiling).
+    #[serde(default = "default_max_trust_level")]
+    pub max_trust_level: FleetTrustLevel,
+    /// Require identity verification for remote workers. When true, SSH
+    /// workers must pass host-key verification before being trusted at
+    /// RemoteVerified level; unverified remotes stay at Sandbox.
+    #[serde(default)]
+    pub require_identity_verification: bool,
+    /// Allow conservative parallel execution of read-only tools (#2983).
+    /// When true, workers may batch independent read-only tool calls
+    /// (reads, searches, greps) into concurrent turns. Disabled by default
+    /// to avoid overwhelming providers or hitting rate limits.
+    #[serde(default)]
+    pub allow_parallel_reads: bool,
+}
+
+fn default_max_trust_level() -> FleetTrustLevel {
+    FleetTrustLevel::Operator
+}
+
+impl Default for FleetSecurityPolicy {
+    fn default() -> Self {
+        Self {
+            default_trust_level: FleetTrustLevel::Sandbox,
+            allowed_secrets: Vec::new(),
+            capability_grants: Vec::new(),
+            max_trust_level: FleetTrustLevel::Operator,
+            require_identity_verification: false,
+            allow_parallel_reads: false,
+        }
+    }
+}
+
+/// A reference to a secret that should be resolved at runtime, never
+/// serialized as a plaintext value.
+///
+/// Secret refs appear in task specs, alert configs, and worker definitions.
+/// The actual secret value is resolved by the fleet manager from the
+/// secrets backend (OS keyring, environment, or file store) just before
+/// the worker starts.
+#[derive(Debug, Clone, Serialize, PartialEq, Eq, Hash, PartialOrd, Ord)]
+pub struct FleetSecretRef {
+    /// The secret key name (e.g. `"CODEWHALE_API_KEY"`, `"GH_TOKEN"`).
+    pub key: String,
+    /// Optional source hint for resolution order.
+    /// - `"env"` — resolve from environment variable
+    /// - `"keyring"` — resolve from OS keyring
+    /// - `"file"` — resolve from `~/.codewhale/secrets/`
+    /// - absent / null — try all sources in default order
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub source: Option<String>,
+}
+
+impl FleetSecretRef {
+    /// Create a secret ref from a key name with default resolution.
+    #[must_use]
+    pub fn new(key: impl Into<String>) -> Self {
+        Self {
+            key: key.into(),
+            source: None,
+        }
+    }
+
+    /// Create a secret ref with an explicit source.
+    #[must_use]
+    pub fn with_source(key: impl Into<String>, source: impl Into<String>) -> Self {
+        Self {
+            key: key.into(),
+            source: Some(source.into()),
+        }
+    }
+
+    /// Redacted display form for logging. Shows the key name and source
+    /// but never the resolved value.
+    #[must_use]
+    pub fn redacted(&self) -> String {
+        match &self.source {
+            Some(src) => format!("<secret:{}.{}>", src, self.key),
+            None => format!("<secret:{}>", self.key),
+        }
+    }
+}
+
+impl std::fmt::Display for FleetSecretRef {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.redacted())
+    }
+}
+
+impl From<&str> for FleetSecretRef {
+    fn from(key: &str) -> Self {
+        Self::new(key)
+    }
+}
+
+impl From<String> for FleetSecretRef {
+    fn from(key: String) -> Self {
+        Self::new(key)
+    }
+}
+
+impl<'de> Deserialize<'de> for FleetSecretRef {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        #[derive(Deserialize)]
+        #[serde(untagged)]
+        enum SecretRefWire {
+            Key(String),
+            Structured {
+                key: String,
+                #[serde(default)]
+                source: Option<String>,
+            },
+        }
+
+        match SecretRefWire::deserialize(deserializer)? {
+            SecretRefWire::Key(key) if !key.trim().is_empty() => Ok(FleetSecretRef::new(key)),
+            SecretRefWire::Key(_) => Err(de::Error::custom("secret ref key cannot be empty")),
+            SecretRefWire::Structured { key, source } if !key.trim().is_empty() => {
+                Ok(FleetSecretRef { key, source })
+            }
+            SecretRefWire::Structured { .. } => {
+                Err(de::Error::custom("secret ref key cannot be empty"))
+            }
+        }
+    }
+}
+
+/// How a worker authenticates to the fleet manager.
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(tag = "method", rename_all = "snake_case")]
+pub enum FleetWorkerAuth {
+    /// No authentication (local workers share the same uid).
+    None,
+    /// SSH key-based authentication with host-key verification.
+    SshKey {
+        /// Path to the SSH identity file (may be a FleetSecretRef in JSON
+        /// as `{"key": "...", "source": "file"}`).
+        identity: PathBuf,
+        /// Known hosts file for host-key verification.
+        #[serde(skip_serializing_if = "Option::is_none")]
+        known_hosts: Option<PathBuf>,
+        /// Expected host key fingerprint for pinning.
+        #[serde(skip_serializing_if = "Option::is_none")]
+        host_key_fingerprint: Option<String>,
+        /// SSH user for the connection.
+        #[serde(skip_serializing_if = "Option::is_none")]
+        user: Option<String>,
+    },
+    /// Token-based authentication for remote workers behind a fleet proxy.
+    Token {
+        /// Reference to the token secret.
+        token_ref: FleetSecretRef,
+    },
+    /// mTLS certificate-based authentication.
+    Mtls {
+        /// Path to the client certificate.
+        cert_path: PathBuf,
+        /// Reference to the private key secret.
+        key_ref: FleetSecretRef,
+    },
+}
+
+/// A capability grant that explicitly authorizes a worker to perform
+/// a specific class of action.
+///
+/// By default, new workers get no grants (least privilege). Grants are
+/// additive: a worker's effective capabilities are the union of its
+/// trust-level defaults plus any explicit grants.
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+pub struct FleetCapabilityGrant {
+    /// The capability being granted (e.g. `"network"`, `"git-push"`,
+    /// `"provider-secrets"`, `"release"`).
+    pub capability: String,
+    /// Optional scope limiting the grant (e.g. `"github.com"` for network,
+    /// `"crates/tui/**"` for file writes).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub scope: Option<String>,
+    /// Optional justification for the grant (audit trail).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub reason: Option<String>,
+}
+
 /// Runtime status of a worker.
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
 #[serde(rename_all = "snake_case")]
@@ -469,18 +742,84 @@ pub enum FleetAlertEventClass {
 #[serde(tag = "kind", rename_all = "snake_case")]
 pub enum FleetAlertChannel {
     Slack {
-        webhook_url: String,
+        /// Webhook URL, resolved from a secret ref or inline.
+        #[serde(flatten)]
+        webhook: FleetAlertEndpoint,
     },
     Webhook {
-        url: String,
-        secret: Option<String>,
+        #[serde(flatten)]
+        endpoint: FleetAlertEndpoint,
     },
+    #[serde(alias = "pager_duty")]
+    #[serde(alias = "pagerduty")]
     PagerDuty {
         routing_key: String,
         severity: String,
     },
 }
 
+/// An alert channel endpoint, supporting both inline URLs and secret refs.
+///
+/// For Slack and generic webhook channels, the URL may be provided directly
+/// or as a secret reference resolved at send time. When both `url` and
+/// `url_ref` are present, `url_ref` takes precedence after resolution.
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+pub struct FleetAlertEndpoint {
+    /// Inline URL (plaintext; only for non-sensitive endpoints).
+    #[serde(
+        alias = "webhook_url",
+        alias = "endpoint_url",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub url: Option<String>,
+    /// Reference to a secret containing the webhook URL.
+    #[serde(
+        alias = "webhook_url_ref",
+        alias = "webhook_ref",
+        alias = "url_secret_ref",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub url_ref: Option<FleetSecretRef>,
+    /// Optional HMAC secret for webhook payload signing, as a secret ref.
+    #[serde(
+        alias = "secret",
+        alias = "webhook_secret",
+        alias = "signing_secret",
+        skip_serializing_if = "Option::is_none"
+    )]
+    pub secret_ref: Option<FleetSecretRef>,
+}
+
+impl FleetAlertEndpoint {
+    /// Create an inline URL endpoint (for non-sensitive use).
+    #[must_use]
+    pub fn inline(url: impl Into<String>) -> Self {
+        Self {
+            url: Some(url.into()),
+            url_ref: None,
+            secret_ref: None,
+        }
+    }
+
+    /// Create a secret-backed URL endpoint.
+    #[must_use]
+    pub fn from_secret(url_ref: FleetSecretRef) -> Self {
+        Self {
+            url: None,
+            url_ref: Some(url_ref),
+            secret_ref: None,
+        }
+    }
+
+    /// Redacted display form for logging.
+    #[must_use]
+    pub fn redacted(&self) -> String {
+        self.url_ref
+            .as_ref()
+            .map_or_else(|| "<inline-url>".to_string(), |r| r.redacted())
+    }
+}
+
 /// Receipt produced when a task completes verification.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct FleetReceipt {
@@ -573,6 +912,7 @@ mod tests {
             }],
             worker_specs: vec![],
             labels: BTreeMap::new(),
+            security_policy: None,
             created_at: "2026-06-12T17:00:00Z".to_string(),
             updated_at: None,
             completed_at: None,
@@ -648,7 +988,7 @@ mod tests {
         let policy = FleetAlertPolicy {
             events: vec![FleetAlertEventClass::Stale],
             channels: vec![FleetAlertChannel::Slack {
-                webhook_url: "https://hooks.slack.com/test".to_string(),
+                webhook: FleetAlertEndpoint::inline("https://hooks.slack.com/test"),
             }],
             after_attempts: Some(2),
             after_minutes_stale: Some(10),
@@ -687,6 +1027,8 @@ mod tests {
                 port,
                 user,
                 identity,
+                known_hosts,
+                host_key_fingerprint,
                 working_directory,
                 env_allowlist,
                 codewhale_binary,
@@ -695,6 +1037,8 @@ mod tests {
                 assert_eq!(port, None);
                 assert_eq!(user, None);
                 assert_eq!(identity, None);
+                assert_eq!(known_hosts, None);
+                assert_eq!(host_key_fingerprint, None);
                 assert_eq!(working_directory, None);
                 assert!(env_allowlist.is_empty());
                 assert_eq!(codewhale_binary, None);
@@ -801,4 +1145,131 @@ mod tests {
         assert_eq!(back.result, FleetTaskResult::Partial);
         assert_eq!(back.failure_kind, Some(FleetTaskFailureKind::Verifier));
     }
+
+    #[test]
+    fn ssh_host_spec_with_key_pinning_round_trip() {
+        let spec = FleetHostSpec::Ssh {
+            host: "builder.trusted.example.com".to_string(),
+            port: Some(22),
+            user: Some("codewhale".to_string()),
+            identity: Some(PathBuf::from("~/.ssh/codewhale_fleet")),
+            known_hosts: Some(PathBuf::from("~/.ssh/known_hosts")),
+            host_key_fingerprint: Some("SHA256:aLGqZo1M6c...".to_string()),
+            working_directory: Some(PathBuf::from("/srv/codewhale/work")),
+            env_allowlist: vec!["CODEWHALE_PROFILE".to_string()],
+            codewhale_binary: Some("/usr/local/bin/codewhale".to_string()),
+        };
+        let json = serde_json::to_string_pretty(&spec).unwrap();
+        assert!(json.contains("\"known_hosts\""));
+        assert!(json.contains("\"host_key_fingerprint\""));
+        assert!(json.contains("SHA256:aLGqZo1M6c..."));
+
+        let back: FleetHostSpec = serde_json::from_str(&json).unwrap();
+        match back {
+            FleetHostSpec::Ssh {
+                host,
+                known_hosts,
+                host_key_fingerprint,
+                ..
+            } => {
+                assert_eq!(host, "builder.trusted.example.com");
+                assert_eq!(known_hosts, Some(PathBuf::from("~/.ssh/known_hosts")));
+                assert_eq!(
+                    host_key_fingerprint,
+                    Some("SHA256:aLGqZo1M6c...".to_string())
+                );
+            }
+            other => panic!("expected ssh host spec, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn secret_ref_redacted_never_exposes_value() {
+        let ref_ = FleetSecretRef::new("DEEPSEEK_API_KEY");
+        let redacted = ref_.redacted();
+        assert!(redacted.contains("DEEPSEEK_API_KEY"));
+        assert!(!redacted.contains("sk-"));
+        assert!(redacted.contains("<secret:"));
+
+        let ref_ = FleetSecretRef::with_source("GH_TOKEN", "env");
+        let redacted = ref_.redacted();
+        assert!(redacted.contains("env.GH_TOKEN"));
+        assert!(!redacted.contains("ghp_"));
+    }
+
+    #[test]
+    fn alert_endpoint_from_secret_round_trip() {
+        let endpoint = FleetAlertEndpoint::from_secret(FleetSecretRef::new("SLACK_WEBHOOK"));
+        let json = serde_json::to_string(&endpoint).unwrap();
+        assert!(json.contains("SLACK_WEBHOOK"));
+        assert!(!json.contains("hooks.slack.com"));
+
+        let back: FleetAlertEndpoint = serde_json::from_str(&json).unwrap();
+        assert_eq!(back.url_ref.as_ref().unwrap().key, "SLACK_WEBHOOK");
+        assert_eq!(back.url, None);
+    }
+
+    #[test]
+    fn secret_ref_accepts_legacy_string_wire_shape() {
+        let ref_: FleetSecretRef = serde_json::from_str(r#""CODEWHALE_FLEET_TOKEN""#).unwrap();
+        assert_eq!(ref_, FleetSecretRef::new("CODEWHALE_FLEET_TOKEN"));
+
+        let ref_: FleetSecretRef =
+            serde_json::from_str(r#"{"key":"GH_TOKEN","source":"env"}"#).unwrap();
+        assert_eq!(ref_, FleetSecretRef::with_source("GH_TOKEN", "env"));
+    }
+
+    #[test]
+    fn trust_level_accepts_hyphenated_remote_verified() {
+        let trust: FleetTrustLevel = serde_json::from_str(r#""remote-verified""#).unwrap();
+        assert_eq!(trust, FleetTrustLevel::RemoteVerified);
+
+        let canonical = serde_json::to_string(&trust).unwrap();
+        assert_eq!(canonical, r#""remote_verified""#);
+    }
+
+    #[test]
+    fn alert_channel_accepts_legacy_webhook_fields() {
+        let channel: FleetAlertChannel = serde_json::from_str(
+            r#"{
+                "kind": "slack",
+                "webhook_url": "https://hooks.slack.com/test",
+                "secret": "SLACK_SIGNING_SECRET"
+            }"#,
+        )
+        .unwrap();
+
+        match channel {
+            FleetAlertChannel::Slack { webhook } => {
+                assert_eq!(webhook.url.as_deref(), Some("https://hooks.slack.com/test"));
+                assert_eq!(
+                    webhook.secret_ref,
+                    Some(FleetSecretRef::new("SLACK_SIGNING_SECRET"))
+                );
+            }
+            other => panic!("expected slack channel, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn security_policy_defaults_are_conservative() {
+        let policy = FleetSecurityPolicy::default();
+        assert_eq!(policy.default_trust_level, FleetTrustLevel::Sandbox);
+        assert!(policy.allowed_secrets.is_empty());
+        assert!(policy.capability_grants.is_empty());
+        assert_eq!(policy.max_trust_level, FleetTrustLevel::Operator);
+        assert!(!policy.require_identity_verification);
+    }
+
+    #[test]
+    fn trust_level_ordinal_reflects_privilege() {
+        assert!(FleetTrustLevel::Operator > FleetTrustLevel::RemoteVerified);
+        assert!(FleetTrustLevel::RemoteVerified > FleetTrustLevel::Local);
+        assert!(FleetTrustLevel::Local > FleetTrustLevel::Sandbox);
+
+        assert!(FleetTrustLevel::Operator.may_access_secrets());
+        assert!(!FleetTrustLevel::Sandbox.may_access_secrets());
+        assert!(!FleetTrustLevel::Sandbox.may_write_workspace());
+        assert!(FleetTrustLevel::Operator.may_write_workspace());
+    }
 }
diff --git a/crates/secrets/src/lib.rs b/crates/secrets/src/lib.rs
index 9e97286f..15506df3 100644
--- a/crates/secrets/src/lib.rs
+++ b/crates/secrets/src/lib.rs
@@ -737,6 +737,44 @@ impl Secrets {
     pub fn get(&self, name: &str) -> Result<Option<String>, SecretsError> {
         self.store.get(name)
     }
+
+    /// Resolve a secret by key name with an optional source constraint.
+    ///
+    /// This is the fleet-worker secret resolution path. Unlike
+    /// [`resolve`](Secrets::resolve), this does NOT map provider names
+    /// to their canonical env vars — the caller controls the exact key
+    /// and resolution order.
+    ///
+    /// `source_hint` controls the resolution order:
+    /// - `Some("env")` — only check environment variables
+    /// - `Some("keyring")` — only check the keyring/file store
+    /// - `None` — try the store first, then fall back to environment
+    #[must_use]
+    pub fn resolve_direct(&self, key: &str, source_hint: Option<&str>) -> Option<String> {
+        match source_hint {
+            Some("env") => {
+                // Only check process environment — skip the store entirely.
+                std::env::var(key).ok().filter(|v| !v.trim().is_empty())
+            }
+            Some("keyring") | Some("file") => {
+                // Only check the store backend.
+                self.store
+                    .get(key)
+                    .ok()
+                    .flatten()
+                    .filter(|v| !v.trim().is_empty())
+            }
+            Some(_) | None => {
+                // Default: store first, then env fallback.
+                if let Ok(Some(v)) = self.store.get(key)
+                    && !v.trim().is_empty()
+                {
+                    return Some(v);
+                }
+                std::env::var(key).ok().filter(|v| !v.trim().is_empty())
+            }
+        }
+    }
 }
 
 /// Map a canonical provider name to its environment variable(s), returning
diff --git a/crates/tui/src/config.rs b/crates/tui/src/config.rs
index 3b60c00c..4dbb0081 100644
--- a/crates/tui/src/config.rs
+++ b/crates/tui/src/config.rs
@@ -1854,6 +1854,10 @@ pub struct Config {
     #[serde(default)]
     pub context: ContextConfig,
 
+    /// Agent Fleet trust/security/role/exec config.
+    #[serde(default)]
+    pub fleet: Option<codewhale_config::FleetConfigToml>,
+
     /// Sub-agent model overrides.
     #[serde(default)]
     pub subagents: Option<SubagentsConfig>,
@@ -4983,6 +4987,7 @@ fn merge_config(base: Config, override_cfg: Config) -> Config {
                 .or(base.context.l3_threshold),
             seam_model: override_cfg.context.seam_model.or(base.context.seam_model),
         },
+        fleet: override_cfg.fleet.or(base.fleet),
         subagents: override_cfg.subagents.or(base.subagents),
         strict_tool_mode: override_cfg.strict_tool_mode.or(base.strict_tool_mode),
         runtime_api: override_cfg.runtime_api.or(base.runtime_api),
diff --git a/crates/tui/src/fleet/host.rs b/crates/tui/src/fleet/host.rs
index 8a4502d9..28c74c9a 100644
--- a/crates/tui/src/fleet/host.rs
+++ b/crates/tui/src/fleet/host.rs
@@ -373,6 +373,8 @@ pub struct SshFleetHostConfig {
     pub user: Option<String>,
     pub port: Option<u16>,
     pub identity: Option<PathBuf>,
+    pub known_hosts: Option<PathBuf>,
+    pub host_key_fingerprint: Option<String>,
     pub working_directory: PathBuf,
     pub env_allowlist: BTreeSet<String>,
     pub codewhale_binary: String,
@@ -387,6 +389,8 @@ impl SshFleetHostConfig {
             user: None,
             port: None,
             identity: None,
+            known_hosts: None,
+            host_key_fingerprint: None,
             working_directory: working_directory.into(),
             env_allowlist: BTreeSet::new(),
             codewhale_binary: "codewhale".to_string(),
@@ -401,6 +405,8 @@ impl SshFleetHostConfig {
             port,
             user,
             identity,
+            known_hosts,
+            host_key_fingerprint,
             working_directory,
             env_allowlist,
             codewhale_binary,
@@ -420,6 +426,8 @@ impl SshFleetHostConfig {
         config.port = *port;
         config.user = user.clone();
         config.identity = identity.clone();
+        config.known_hosts = known_hosts.clone();
+        config.host_key_fingerprint = host_key_fingerprint.clone();
         config.env_allowlist = env_allowlist.iter().cloned().collect();
         config.codewhale_binary = codewhale_binary;
         config.validate()?;
@@ -918,6 +926,8 @@ mod tests {
             port: Some(2222),
             user: Some("fleet".to_string()),
             identity: Some(PathBuf::from("/tmp/fleet_id")),
+            known_hosts: None,
+            host_key_fingerprint: None,
             working_directory: Some(PathBuf::from("/srv/codewhale")),
             env_allowlist: vec!["FLEET_PROFILE".to_string()],
             codewhale_binary: Some("/usr/local/bin/codewhale".to_string()),
diff --git a/crates/tui/src/fleet/ledger.rs b/crates/tui/src/fleet/ledger.rs
index 37d2cfdd..7b863bf9 100644
--- a/crates/tui/src/fleet/ledger.rs
+++ b/crates/tui/src/fleet/ledger.rs
@@ -661,12 +661,21 @@ fn sanitize_run_for_ledger(run: &FleetRun) -> FleetRun {
         if let Some(policy) = &mut task.alert_policy {
             for channel in &mut policy.channels {
                 match channel {
-                    FleetAlertChannel::Slack { webhook_url } => {
-                        *webhook_url = "<redacted>".to_string();
+                    FleetAlertChannel::Slack { webhook } => {
+                        webhook.url = webhook.url.as_ref().map(|_| "<redacted>".to_string());
                     }
-                    FleetAlertChannel::Webhook { url, secret } => {
-                        *url = "<redacted>".to_string();
-                        *secret = secret.as_ref().map(|_| "<redacted>".to_string());
+                    FleetAlertChannel::Webhook { endpoint } => {
+                        *endpoint = FleetAlertEndpoint {
+                            url: endpoint.url.as_ref().map(|_| "<redacted>".to_string()),
+                            url_ref: endpoint
+                                .url_ref
+                                .as_ref()
+                                .map(|_| FleetSecretRef::new("<redacted>")),
+                            secret_ref: endpoint
+                                .secret_ref
+                                .as_ref()
+                                .map(|_| FleetSecretRef::new("<redacted>")),
+                        };
                     }
                     FleetAlertChannel::PagerDuty { routing_key, .. } => {
                         *routing_key = "<redacted>".to_string();
@@ -691,6 +700,7 @@ mod tests {
             task_specs: vec![],
             worker_specs: vec![],
             labels: BTreeMap::new(),
+            security_policy: None,
             created_at: "2026-06-12T17:00:00Z".to_string(),
             updated_at: None,
             completed_at: None,
diff --git a/crates/tui/src/fleet/manager.rs b/crates/tui/src/fleet/manager.rs
index cf2fdb2a..9f8ff6fb 100644
--- a/crates/tui/src/fleet/manager.rs
+++ b/crates/tui/src/fleet/manager.rs
@@ -21,14 +21,38 @@ use super::task_spec::{
     FleetTaskSpecDocument, FleetTaskVerificationInput, load_task_spec_document,
     record_verification_receipt, validate_task_spec_document, verify_task_result,
 };
+use super::worker_runtime;
+use crate::tools::subagent::SharedSubAgentManager;
 
 const DEFAULT_STALE_AFTER_SECONDS: u64 = 300;
 
-#[derive(Debug)]
 pub struct FleetManager {
     workspace: PathBuf,
     ledger: FleetLedger,
     stale_after: Duration,
+    exec_config: codewhale_config::FleetExecConfig,
+    /// Optional sub-agent manager for headless worker execution.
+    /// When set, fleet workers spawn real sub-agents; when None,
+    /// the manager falls back to local simulation.
+    sub_agent_manager: Option<SharedSubAgentManager>,
+}
+
+impl std::fmt::Debug for FleetManager {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("FleetManager")
+            .field("workspace", &self.workspace)
+            .field("ledger", &self.ledger)
+            .field("stale_after", &self.stale_after)
+            .field("exec_config", &self.exec_config)
+            .field(
+                "sub_agent_manager",
+                &self
+                    .sub_agent_manager
+                    .as_ref()
+                    .map(|_| "SharedSubAgentManager"),
+            )
+            .finish()
+    }
 }
 
 #[derive(Debug, Clone)]
@@ -78,6 +102,28 @@ pub struct FleetWorkerInspection {
     pub artifacts: Vec<FleetArtifactRef>,
     pub last_error: Option<String>,
     pub alert_state: Option<String>,
+    /// Lightweight projection from the sub-agent worker runtime.
+    /// Populated when a sub-agent manager is attached.
+    pub runtime_state: Option<FleetWorkerRuntimeProjection>,
+}
+
+/// Lightweight TUI projection of a headless sub-agent worker's current state.
+///
+/// Derived from the sub-agent manager's `AgentWorkerRecord`.
+#[derive(Debug, Clone)]
+pub struct FleetWorkerRuntimeProjection {
+    /// Sub-agent lifecycle status (Queued, Starting, Running, Completed, etc.)
+    pub agent_status: String,
+    /// Steps taken so far (tool calls + model turns)
+    pub steps_taken: u32,
+    /// Latest human-readable message from the worker
+    pub latest_message: Option<String>,
+    /// Error message if the worker failed
+    pub error: Option<String>,
+    /// Result summary if the worker completed
+    pub result_summary: Option<String>,
+    /// Whether the worker has a sub-agent session running
+    pub has_session: bool,
 }
 
 impl FleetManager {
@@ -88,6 +134,8 @@ impl FleetManager {
             workspace,
             ledger,
             stale_after: Duration::from_secs(DEFAULT_STALE_AFTER_SECONDS),
+            exec_config: codewhale_config::FleetExecConfig::default(),
+            sub_agent_manager: None,
         })
     }
 
@@ -96,6 +144,23 @@ impl FleetManager {
         self
     }
 
+    /// Apply fleet headless-worker execution policy from config.
+    pub fn with_exec_config(mut self, exec_config: codewhale_config::FleetExecConfig) -> Self {
+        self.exec_config = exec_config;
+        self
+    }
+
+    /// Attach a sub-agent manager so fleet workers can spawn real headless agents.
+    pub fn with_sub_agent_manager(mut self, mgr: SharedSubAgentManager) -> Self {
+        self.sub_agent_manager = Some(mgr);
+        self
+    }
+
+    /// True when the manager has a sub-agent runtime for headless worker execution.
+    pub fn has_worker_runtime(&self) -> bool {
+        self.sub_agent_manager.is_some()
+    }
+
     pub fn ledger_path(&self) -> &Path {
         self.ledger.path()
     }
@@ -139,6 +204,7 @@ impl FleetManager {
             task_specs: doc.tasks.clone(),
             worker_specs: doc.workers.clone(),
             labels: doc.labels,
+            security_policy: doc.security_policy.clone(),
             created_at: now.clone(),
             updated_at: Some(now.clone()),
             completed_at: None,
@@ -280,6 +346,27 @@ impl FleetManager {
             .get(worker_id)
             .map(|heartbeat| heartbeat.timestamp.clone());
         let alert_state = latest_alert_for_worker(&state, worker_id);
+
+        // Enrich with sub-agent worker runtime state when available.
+        let runtime_state = self.sub_agent_manager.as_ref().and_then(|mgr| {
+            mgr.try_read()
+                .ok()
+                .and_then(|guard| guard.get_worker_record(worker_id))
+                .map(|record| FleetWorkerRuntimeProjection {
+                    agent_status: format!("{:?}", record.status).to_lowercase(),
+                    steps_taken: record.steps_taken,
+                    latest_message: record.latest_message,
+                    error: record.error,
+                    result_summary: record.result_summary,
+                    has_session: !matches!(
+                        record.status,
+                        crate::tools::subagent::AgentWorkerStatus::Completed
+                            | crate::tools::subagent::AgentWorkerStatus::Failed
+                            | crate::tools::subagent::AgentWorkerStatus::Cancelled
+                    ),
+                })
+        });
+
         Ok(FleetWorkerInspection {
             worker_id: worker_id.to_string(),
             status,
@@ -293,6 +380,7 @@ impl FleetManager {
             artifacts,
             last_error,
             alert_state,
+            runtime_state,
         })
     }
 
@@ -475,6 +563,45 @@ impl FleetManager {
             FleetWorkerEventPayload::Running,
         )?;
         self.ledger.heartbeat(worker_id, &timestamp(), None, None)?;
+
+        // Register with the sub-agent manager for headless worker tracking.
+        // The engine's agent_open path handles actual sub-agent spawning.
+        if let Some(ref mgr) = self.sub_agent_manager {
+            if let Ok(guard) = mgr.try_write() {
+                let run = self
+                    .ledger
+                    .rebuild_state()
+                    .ok()
+                    .and_then(|state| state.runs.get(&entry.run_id.0).cloned());
+                let worker_spec = run
+                    .as_ref()
+                    .and_then(|r| r.worker_specs.iter().find(|w| w.id == worker_id).cloned())
+                    .unwrap_or_else(|| FleetWorkerSpec {
+                        id: worker_id.to_string(),
+                        name: worker_id.to_string(),
+                        host: FleetHostSpec::Local,
+                        trust_level: Some(FleetTrustLevel::Local),
+                        labels: BTreeMap::new(),
+                        capabilities: vec![],
+                        max_concurrent_tasks: Some(1),
+                    });
+                let worker = worker_runtime::fleet_task_to_worker_spec(
+                    worker_id,
+                    &entry.run_id.0,
+                    task_spec,
+                    &worker_spec,
+                    "auto",
+                    &self.workspace,
+                );
+                let worker = worker_runtime::apply_exec_hardening(worker, &self.exec_config);
+                // drop guard after registering so we don't hold the write lock
+                drop(guard);
+                if let Ok(mut guard) = mgr.try_write() {
+                    guard.register_worker(worker);
+                }
+            }
+        }
+
         self.maybe_complete_local_simulation(entry, worker_id, task_spec, log_artifact)
     }
 
@@ -746,6 +873,7 @@ fn default_local_workers(run_id: &FleetRunId, max_workers: usize) -> Vec<FleetWo
             id: format!("{}-local-{}", run_id.0, index),
             name: format!("Local worker {index}"),
             host: FleetHostSpec::Local,
+            trust_level: Some(FleetTrustLevel::Local),
             labels: BTreeMap::new(),
             capabilities: vec!["local".to_string()],
             max_concurrent_tasks: Some(1),
@@ -1267,4 +1395,159 @@ mod tests {
             Some("escalated via pagerduty alert_id=alert-1")
         );
     }
+
+    #[test]
+    fn fleet_dogfood_smoke_run_two_local_workers_two_tasks() {
+        let tmp = TempDir::new().unwrap();
+        let workspace = tmp.path().join("repo");
+        std::fs::create_dir_all(&workspace).unwrap();
+        // Create a minimal Cargo.toml so the cargo-check task can succeed.
+        std::fs::write(
+            workspace.join("Cargo.toml"),
+            "[package]\nname = \"smoke\"\nversion = \"0.1.0\"\nedition = \"2021\"\n",
+        )
+        .unwrap();
+        std::fs::create_dir_all(workspace.join("src")).unwrap();
+        std::fs::write(
+            workspace.join("src").join("lib.rs"),
+            "pub fn answer() -> u8 { 42 }\n",
+        )
+        .unwrap();
+
+        let tasks = vec![
+            FleetTaskSpec {
+                id: "check".to_string(),
+                name: "check".to_string(),
+                description: None,
+                objective: Some("cargo check".to_string()),
+                instructions: "run cargo check and report result".to_string(),
+                worker: Some(FleetTaskWorkerProfile {
+                    role: Some("release-checker".to_string()),
+                    tool_profile: Some("read-only".to_string()),
+                    tools: vec!["cargo".to_string()],
+                    capabilities: vec!["rust".to_string()],
+                }),
+                workspace: Some(FleetWorkspaceRequirements {
+                    root: None,
+                    required_files: vec![PathBuf::from("Cargo.toml")],
+                    writable_paths: vec![PathBuf::from(".codewhale/fleet")],
+                    environment: Some(FleetEnvironmentRequirements {
+                        required: vec!["PATH".to_string()],
+                        allowlist: vec![],
+                    }),
+                }),
+                input_files: vec![],
+                context: vec![],
+                budget: None,
+                tags: vec!["smoke".to_string()],
+                expected_artifacts: vec![FleetArtifactKind::Log, FleetArtifactKind::Receipt],
+                scorer: Some(FleetScorerSpec::ExitCode),
+                retry_policy: Some(FleetRetryPolicy {
+                    max_attempts: 1,
+                    ..Default::default()
+                }),
+                alert_policy: None,
+                timeout_seconds: Some(60),
+                metadata: BTreeMap::new(),
+            },
+            FleetTaskSpec {
+                id: "review".to_string(),
+                name: "review".to_string(),
+                description: None,
+                objective: Some("review source".to_string()),
+                instructions: "read src/lib.rs and report findings".to_string(),
+                worker: Some(FleetTaskWorkerProfile {
+                    role: Some("reviewer".to_string()),
+                    tool_profile: Some("read-only".to_string()),
+                    tools: vec!["cargo".to_string()],
+                    capabilities: vec!["rust".to_string()],
+                }),
+                workspace: Some(FleetWorkspaceRequirements {
+                    root: None,
+                    required_files: vec![],
+                    writable_paths: vec![],
+                    environment: Some(FleetEnvironmentRequirements {
+                        required: vec!["PATH".to_string()],
+                        allowlist: vec![],
+                    }),
+                }),
+                input_files: vec![],
+                context: vec![],
+                budget: None,
+                tags: vec!["smoke".to_string()],
+                expected_artifacts: vec![FleetArtifactKind::Log, FleetArtifactKind::Receipt],
+                scorer: None,
+                retry_policy: Some(FleetRetryPolicy {
+                    max_attempts: 1,
+                    ..Default::default()
+                }),
+                alert_policy: None,
+                timeout_seconds: Some(60),
+                metadata: BTreeMap::new(),
+            },
+        ];
+
+        let manager = FleetManager::open(&workspace).unwrap();
+        let report = manager
+            .create_run(
+                FleetTaskSpecDocument {
+                    name: Some("dogfood smoke".to_string()),
+                    labels: BTreeMap::new(),
+                    security_policy: Some(FleetSecurityPolicy {
+                        default_trust_level: FleetTrustLevel::Local,
+                        ..Default::default()
+                    }),
+                    workers: vec![],
+                    tasks,
+                },
+                2,
+            )
+            .unwrap();
+
+        assert_eq!(report.task_count, 2);
+        assert!(!report.worker_ids.is_empty());
+        assert_eq!(report.worker_ids.len(), 2);
+        // After immediate scheduling, tasks may already be leased,
+        // so queued+running should total 2.
+        let status = manager.run_status(&report.run_id).unwrap();
+        assert_eq!(status.queued + status.running, 2);
+    }
+
+    #[test]
+    fn fleet_security_policy_propagates_from_task_spec_document_to_run() {
+        let tmp = TempDir::new().unwrap();
+        let manager = FleetManager::open(tmp.path()).unwrap();
+        let path = task_spec_file(&tmp, vec![task("task-a")]);
+        // Rewrite the spec file with a security_policy block.
+        let doc = serde_json::json!({
+            "name": "secure smoke",
+            "tasks": [{
+                "id": "task-a",
+                "name": "task-a",
+                "instructions": "report ok",
+                "expected_artifacts": ["log"]
+            }],
+            "security_policy": {
+                "default_trust_level": "local",
+                "allowed_secrets": [{"key": "GH_TOKEN", "source": "env"}],
+                "max_trust_level": "remote_verified",
+                "require_identity_verification": true
+            }
+        });
+        let spec_path = tmp.path().join("secure-tasks.json");
+        std::fs::write(&spec_path, serde_json::to_string_pretty(&doc).unwrap()).unwrap();
+
+        let report = manager
+            .create_run_from_task_spec_path(&spec_path, 1)
+            .unwrap();
+
+        let state = manager.ledger.rebuild_state().unwrap();
+        let run = state.runs.get(&report.run_id.0).unwrap();
+        let policy = run.security_policy.as_ref().unwrap();
+        assert_eq!(policy.default_trust_level, FleetTrustLevel::Local);
+        assert_eq!(policy.allowed_secrets.len(), 1);
+        assert_eq!(policy.allowed_secrets[0].key, "GH_TOKEN");
+        assert_eq!(policy.max_trust_level, FleetTrustLevel::RemoteVerified);
+        assert!(policy.require_identity_verification);
+    }
 }
diff --git a/crates/tui/src/fleet/mod.rs b/crates/tui/src/fleet/mod.rs
index 6a57779c..7258e893 100644
--- a/crates/tui/src/fleet/mod.rs
+++ b/crates/tui/src/fleet/mod.rs
@@ -6,3 +6,4 @@ pub mod ledger;
 pub mod manager;
 pub mod scheduler;
 pub mod task_spec;
+pub mod worker_runtime;
diff --git a/crates/tui/src/fleet/scheduler.rs b/crates/tui/src/fleet/scheduler.rs
index dc15a770..b62a33a8 100644
--- a/crates/tui/src/fleet/scheduler.rs
+++ b/crates/tui/src/fleet/scheduler.rs
@@ -573,6 +573,7 @@ mod tests {
             id: id.to_string(),
             name: id.to_string(),
             host: FleetHostSpec::Local,
+            trust_level: Some(FleetTrustLevel::Local),
             labels: BTreeMap::new(),
             capabilities: vec!["local".to_string()],
             max_concurrent_tasks: Some(1),
@@ -622,6 +623,7 @@ mod tests {
                     .map(|idx| worker(&format!("worker-{idx}")))
                     .collect(),
                 labels: BTreeMap::new(),
+                security_policy: None,
                 created_at: scheduler.timestamp(),
                 updated_at: None,
                 completed_at: None,
@@ -704,7 +706,7 @@ mod tests {
         failing.alert_policy = Some(FleetAlertPolicy {
             events: vec![FleetAlertEventClass::RestartExhausted],
             channels: vec![FleetAlertChannel::Slack {
-                webhook_url: "https://hooks.slack.invalid/secret".to_string(),
+                webhook: FleetAlertEndpoint::inline("https://hooks.slack.invalid/secret"),
             }],
             after_attempts: Some(1),
             after_minutes_stale: Some(1),
diff --git a/crates/tui/src/fleet/task_spec.rs b/crates/tui/src/fleet/task_spec.rs
index 1dfcdadc..f0425d7f 100644
--- a/crates/tui/src/fleet/task_spec.rs
+++ b/crates/tui/src/fleet/task_spec.rs
@@ -23,6 +23,9 @@ pub struct FleetTaskSpecDocument {
     pub name: Option<String>,
     #[serde(default)]
     pub labels: BTreeMap<String, String>,
+    #[serde(default)]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub security_policy: Option<FleetSecurityPolicy>,
     #[serde(default, alias = "worker_specs")]
     pub workers: Vec<FleetWorkerSpec>,
     #[serde(default)]
@@ -49,12 +52,14 @@ impl FleetTaskSpecFile {
             Self::Tasks(tasks) => FleetTaskSpecDocument {
                 name: Some(fallback_name),
                 labels: BTreeMap::new(),
+                security_policy: None,
                 workers: Vec::new(),
                 tasks,
             },
             Self::Single(task) => FleetTaskSpecDocument {
                 name: Some(fallback_name),
                 labels: BTreeMap::new(),
+                security_policy: None,
                 workers: Vec::new(),
                 tasks: vec![task],
             },
diff --git a/crates/tui/src/fleet/worker_runtime.rs b/crates/tui/src/fleet/worker_runtime.rs
new file mode 100644
index 00000000..9b9f2137
--- /dev/null
+++ b/crates/tui/src/fleet/worker_runtime.rs
@@ -0,0 +1,626 @@
+//! Fleet worker runtime — bridges fleet task specs to headless sub-agent execution.
+//!
+//! This module makes fleet workers real: instead of simulating task completion,
+//! each fleet worker spawns a headless sub-agent that runs the task instructions
+//! and streams progress back into the fleet ledger.
+//!
+//! Architecture:
+//! - `FleetTaskSpec` + `FleetWorkerSpec` → `AgentWorkerSpec`
+//! - `SubAgentManager::register_worker()` tracks the worker
+//! - Sub-agent spawn happens through the existing `agent_open` machinery
+//! - Mailbox events stream into fleet ledger as `FleetWorkerEventPayload`
+//! - `FleetWorkerInspection` reads both ledger state and sub-agent worker records
+
+#![allow(dead_code)]
+
+use codewhale_protocol::fleet::{
+    FleetHostSpec, FleetTaskSpec, FleetTaskWorkerProfile, FleetWorkerEventPayload, FleetWorkerSpec,
+};
+
+use super::host::FleetHostKind;
+use crate::tools::subagent::{
+    AgentWorkerSpec, AgentWorkerStatus, AgentWorkerToolProfile, SubAgentType,
+};
+
+/// Map a fleet worker spec's host kind to a display string.
+pub fn fleet_host_kind_for_spec(spec: &FleetWorkerSpec) -> FleetHostKind {
+    match &spec.host {
+        FleetHostSpec::Local => FleetHostKind::LocalProcess,
+        FleetHostSpec::Ssh { .. } => FleetHostKind::Ssh,
+        FleetHostSpec::Docker { .. } => FleetHostKind::LocalProcess, // Docker runs local-ish
+    }
+}
+
+/// Map a fleet host kind to a compact display label.
+pub fn fleet_host_kind_label(kind: FleetHostKind) -> &'static str {
+    match kind {
+        FleetHostKind::LocalProcess => "local",
+        FleetHostKind::Ssh => "ssh",
+    }
+}
+
+/// Build a sub-agent `AgentWorkerSpec` from a fleet task spec and worker spec.
+///
+/// The fleet task's `instructions` become the sub-agent's `objective`, the
+/// `worker.role` maps to a `SubAgentType`, and tool/capability restrictions
+/// become an `AgentWorkerToolProfile`.
+pub fn fleet_task_to_worker_spec(
+    worker_id: &str,
+    run_id: &str,
+    task_spec: &FleetTaskSpec,
+    _worker_spec: &FleetWorkerSpec,
+    model: &str,
+    workspace: &std::path::Path,
+) -> AgentWorkerSpec {
+    let agent_type =
+        fleet_role_to_agent_type(task_spec.worker.as_ref().and_then(|w| w.role.as_deref()));
+
+    let tool_profile = fleet_tool_profile(task_spec.worker.as_ref());
+
+    let objective = fleet_task_prompt(task_spec);
+
+    AgentWorkerSpec {
+        worker_id: worker_id.to_string(),
+        run_id: run_id.to_string(),
+        parent_run_id: None,
+        session_name: Some(format!("fleet-{}-{}", worker_id, task_spec.id)),
+        objective,
+        role: task_spec.worker.as_ref().and_then(|w| w.role.clone()),
+        agent_type,
+        model: model.to_string(),
+        workspace: workspace.to_path_buf(),
+        git_branch: None,
+        context_mode: "fresh".to_string(),
+        fork_context: false,
+        tool_profile,
+        max_steps: task_spec
+            .budget
+            .as_ref()
+            .and_then(|b| b.max_tool_calls)
+            .unwrap_or(u32::MAX),
+        spawn_depth: 0,
+        max_spawn_depth: codewhale_config::FleetExecConfig::default().max_spawn_depth,
+    }
+}
+
+fn fleet_task_prompt(task_spec: &FleetTaskSpec) -> String {
+    let mut prompt = String::new();
+    prompt.push_str("Fleet task: ");
+    prompt.push_str(&task_spec.name);
+
+    if let Some(objective) = task_spec.objective.as_deref() {
+        prompt.push_str("\n\nObjective:\n");
+        prompt.push_str(objective);
+    } else if let Some(description) = task_spec.description.as_deref() {
+        prompt.push_str("\n\nObjective:\n");
+        prompt.push_str(description);
+    }
+
+    prompt.push_str("\n\nInstructions:\n");
+    prompt.push_str(&task_spec.instructions);
+
+    if !task_spec.context.is_empty() {
+        prompt.push_str("\n\nContext:\n");
+        for item in &task_spec.context {
+            prompt.push_str("- ");
+            prompt.push_str(item);
+            prompt.push('\n');
+        }
+    }
+
+    if !task_spec.input_files.is_empty() {
+        prompt.push_str("\nInput files:\n");
+        for path in &task_spec.input_files {
+            prompt.push_str("- ");
+            prompt.push_str(&path.display().to_string());
+            prompt.push('\n');
+        }
+    }
+
+    prompt
+}
+
+/// Map a fleet role name to a `SubAgentType`. Unknown roles default to `General`.
+fn fleet_role_to_agent_type(role: Option<&str>) -> SubAgentType {
+    match role {
+        Some("smoke-runner") | Some("read-only") => SubAgentType::ToolAgent,
+        Some("reviewer") => SubAgentType::Review,
+        Some("builder") => SubAgentType::Implementer,
+        Some("verifier") | Some("tester") => SubAgentType::Verifier,
+        Some("planner") => SubAgentType::Plan,
+        Some("explorer") => SubAgentType::Explore,
+        Some("general") | None => SubAgentType::General,
+        Some(other) => {
+            // Try parsing as a SubAgentType directly
+            SubAgentType::from_str(other).unwrap_or(SubAgentType::General)
+        }
+    }
+}
+
+/// Convert a fleet worker profile's tool list into an `AgentWorkerToolProfile`.
+fn fleet_tool_profile(profile: Option<&FleetTaskWorkerProfile>) -> AgentWorkerToolProfile {
+    match profile {
+        Some(p) if !p.tools.is_empty() => AgentWorkerToolProfile::Explicit(p.tools.clone()),
+        _ => AgentWorkerToolProfile::Inherited,
+    }
+}
+
+/// Create a fleet artifact ref from a worker output.
+///
+/// Uses the fleet artifact conventions: logs go under `.codewhale/fleet/`,
+/// reports under `.codewhale/fleet/reports/`.
+pub fn fleet_artifact_ref(
+    _run_id: &str,
+    _worker_id: &str,
+    kind: codewhale_protocol::fleet::FleetArtifactKind,
+    path: std::path::PathBuf,
+) -> codewhale_protocol::fleet::FleetArtifactRef {
+    codewhale_protocol::fleet::FleetArtifactRef {
+        kind,
+        path,
+        checksum: None,
+        mime_type: None,
+        size_bytes: None,
+    }
+}
+
+/// Map a sub-agent `AgentWorkerStatus` to a fleet `FleetWorkerEventPayload`.
+///
+/// This is the streaming bridge: as the sub-agent runs, each status transition
+/// produces a corresponding fleet ledger event so the TUI surfaces stay in sync.
+pub fn agent_status_to_fleet_event(
+    status: AgentWorkerStatus,
+    message: Option<&str>,
+    tool_name: Option<&str>,
+) -> FleetWorkerEventPayload {
+    match status {
+        AgentWorkerStatus::Queued => FleetWorkerEventPayload::Queued,
+        AgentWorkerStatus::Starting => FleetWorkerEventPayload::Starting,
+        AgentWorkerStatus::Running => FleetWorkerEventPayload::Running,
+        AgentWorkerStatus::WaitingForUser => FleetWorkerEventPayload::ModelWait { model: None },
+        AgentWorkerStatus::ModelWait => FleetWorkerEventPayload::ModelWait { model: None },
+        AgentWorkerStatus::RunningTool => FleetWorkerEventPayload::RunningTool {
+            tool: tool_name.unwrap_or("unknown").to_string(),
+            call_id: None,
+        },
+        AgentWorkerStatus::Completed => FleetWorkerEventPayload::Completed {
+            exit_code: Some(0),
+            summary: message.map(|s| s.to_string()),
+        },
+        AgentWorkerStatus::Failed => FleetWorkerEventPayload::Failed {
+            reason: message.unwrap_or("unknown error").to_string(),
+            recoverable: false,
+        },
+        AgentWorkerStatus::Cancelled => FleetWorkerEventPayload::Cancelled { cancelled_by: None },
+        AgentWorkerStatus::Interrupted => FleetWorkerEventPayload::Interrupted {
+            signal: message.map(|s| s.to_string()),
+        },
+    }
+}
+
+/// Apply exec hardening to a worker spec from fleet config (#3027).
+///
+/// Filters tools against allowed/disallowed lists, caps max_steps to
+/// config's max_turns, and returns the objective with system prompt
+/// appended when configured.
+pub fn apply_exec_hardening(
+    mut spec: AgentWorkerSpec,
+    exec: &codewhale_config::FleetExecConfig,
+) -> AgentWorkerSpec {
+    // Cap max_steps to config max_turns
+    if exec.max_turns > 0 && exec.max_turns != u32::MAX {
+        spec.max_steps = spec.max_steps.min(exec.max_turns);
+    }
+    spec.max_spawn_depth = exec
+        .max_spawn_depth
+        .min(codewhale_config::MAX_SPAWN_DEPTH_CEILING);
+
+    // Apply tool filtering
+    if !exec.allowed_tools.is_empty() || !exec.disallowed_tools.is_empty() {
+        spec.tool_profile = filter_tool_profile(&spec.tool_profile, exec);
+    }
+
+    // Append system prompt
+    if !exec.append_system_prompt.is_empty() {
+        spec.objective = format!(
+            "{}\n\n[Policy]\n{}",
+            spec.objective, exec.append_system_prompt
+        );
+    }
+
+    spec
+}
+
+/// Filter a tool profile against allowed/disallowed lists.
+fn filter_tool_profile(
+    profile: &AgentWorkerToolProfile,
+    exec: &codewhale_config::FleetExecConfig,
+) -> AgentWorkerToolProfile {
+    match profile {
+        AgentWorkerToolProfile::Explicit(tools) => {
+            let filtered: Vec<String> = tools
+                .iter()
+                .filter(|t| {
+                    // If allowed_tools is non-empty, only keep tools in the list
+                    if !exec.allowed_tools.is_empty() && !exec.allowed_tools.contains(t) {
+                        return false;
+                    }
+                    // Disallowed tools always win
+                    !exec.disallowed_tools.contains(t)
+                })
+                .cloned()
+                .collect();
+            AgentWorkerToolProfile::Explicit(filtered)
+        }
+        AgentWorkerToolProfile::Inherited => {
+            // Inherited profiles can't be filtered at spec time;
+            // the sub-agent spawn path applies tool filtering.
+            AgentWorkerToolProfile::Inherited
+        }
+    }
+}
+
+/// Determine whether a tool is safe for parallel execution (#2983).
+///
+/// Read-only tools that don't mutate state and have no side effects
+/// are candidates for conservative parallel batching.
+pub fn is_parallel_safe_read_only_tool(tool_name: &str) -> bool {
+    matches!(
+        tool_name,
+        "read_file"
+            | "grep_files"
+            | "file_search"
+            | "list_dir"
+            | "git_status"
+            | "git_diff"
+            | "git_log"
+            | "git_show"
+            | "git_blame"
+            | "fetch_url"
+            | "web_search"
+            | "tool_search_tool_regex"
+            | "tool_search_tool_bm25"
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn fleet_role_smoke_runner_maps_to_tool_agent() {
+        assert_eq!(
+            fleet_role_to_agent_type(Some("smoke-runner")),
+            SubAgentType::ToolAgent
+        );
+    }
+
+    #[test]
+    fn fleet_role_reviewer_maps_to_review() {
+        assert_eq!(
+            fleet_role_to_agent_type(Some("reviewer")),
+            SubAgentType::Review
+        );
+    }
+
+    #[test]
+    fn fleet_role_builder_maps_to_implementer() {
+        assert_eq!(
+            fleet_role_to_agent_type(Some("builder")),
+            SubAgentType::Implementer
+        );
+    }
+
+    #[test]
+    fn fleet_role_none_maps_to_general() {
+        assert_eq!(fleet_role_to_agent_type(None), SubAgentType::General);
+    }
+
+    #[test]
+    fn unknown_role_maps_to_general() {
+        assert_eq!(
+            fleet_role_to_agent_type(Some("nonexistent-role")),
+            SubAgentType::General
+        );
+    }
+
+    #[test]
+    fn fleet_tool_profile_empty_uses_inherited() {
+        let profile = FleetTaskWorkerProfile {
+            role: None,
+            tool_profile: None,
+            tools: vec![],
+            capabilities: vec![],
+        };
+        assert_eq!(
+            fleet_tool_profile(Some(&profile)),
+            AgentWorkerToolProfile::Inherited
+        );
+    }
+
+    #[test]
+    fn fleet_tool_profile_explicit_passes_tools() {
+        let profile = FleetTaskWorkerProfile {
+            role: None,
+            tool_profile: None,
+            tools: vec!["cargo".to_string(), "git".to_string()],
+            capabilities: vec![],
+        };
+        assert_eq!(
+            fleet_tool_profile(Some(&profile)),
+            AgentWorkerToolProfile::Explicit(vec!["cargo".to_string(), "git".to_string()])
+        );
+    }
+
+    #[test]
+    fn fleet_task_prompt_includes_instructions_context_and_input_files() {
+        let task = FleetTaskSpec {
+            id: "review".to_string(),
+            name: "Review protocol".to_string(),
+            description: None,
+            objective: Some("Find protocol regressions".to_string()),
+            instructions: "Read the fleet protocol and report issues.".to_string(),
+            worker: None,
+            workspace: None,
+            input_files: vec![std::path::PathBuf::from("crates/protocol/src/fleet.rs")],
+            context: vec!["Keep the report concise.".to_string()],
+            budget: None,
+            tags: vec![],
+            expected_artifacts: vec![],
+            scorer: None,
+            retry_policy: None,
+            alert_policy: None,
+            timeout_seconds: None,
+            metadata: Default::default(),
+        };
+
+        let prompt = fleet_task_prompt(&task);
+
+        assert!(prompt.contains("Review protocol"));
+        assert!(prompt.contains("Find protocol regressions"));
+        assert!(prompt.contains("Read the fleet protocol and report issues."));
+        assert!(prompt.contains("Keep the report concise."));
+        assert!(prompt.contains("crates/protocol/src/fleet.rs"));
+    }
+
+    #[test]
+    fn fleet_worker_spec_defaults_to_shared_subagent_spawn_depth() {
+        let task = FleetTaskSpec {
+            id: "task-1".to_string(),
+            name: "Task".to_string(),
+            description: None,
+            objective: None,
+            instructions: "Do the task.".to_string(),
+            worker: None,
+            workspace: None,
+            input_files: vec![],
+            context: vec![],
+            budget: None,
+            tags: vec![],
+            expected_artifacts: vec![],
+            scorer: None,
+            retry_policy: None,
+            alert_policy: None,
+            timeout_seconds: None,
+            metadata: Default::default(),
+        };
+        let worker = FleetWorkerSpec {
+            id: "worker-1".to_string(),
+            name: "Worker".to_string(),
+            host: FleetHostSpec::Local,
+            trust_level: None,
+            labels: Default::default(),
+            capabilities: vec![],
+            max_concurrent_tasks: None,
+        };
+
+        let spec = fleet_task_to_worker_spec(
+            "worker-1",
+            "run-1",
+            &task,
+            &worker,
+            "auto",
+            std::path::Path::new("/tmp"),
+        );
+
+        // Root fleet worker runs at depth 0; its budget equals the shared
+        // sub-agent default (3) so fleet and sub-agents are one substrate and
+        // at least 3 nested delegation levels are afforded.
+        assert_eq!(spec.spawn_depth, 0);
+        assert_eq!(spec.max_spawn_depth, codewhale_config::DEFAULT_SPAWN_DEPTH);
+        assert_eq!(spec.max_spawn_depth, 3);
+
+        // End-to-end reachability: walk the SAME gate the SubAgentRuntime
+        // enforces (`would_exceed_depth` = `spawn_depth + 1 > max_spawn_depth`).
+        // A depth-0 root must reach 3 nested levels, then stop. This fails if
+        // anyone lowers the shared default below 3 (Hunter: afford >= 3).
+        let hardened = apply_exec_hardening(spec, &codewhale_config::FleetExecConfig::default());
+        let would_exceed = |spawn_depth: u32| spawn_depth + 1 > hardened.max_spawn_depth;
+        assert!(
+            !would_exceed(0),
+            "root (depth 0) must spawn a child at depth 1"
+        );
+        assert!(!would_exceed(1), "depth-1 child must spawn to depth 2");
+        assert!(!would_exceed(2), "depth-2 child must spawn to depth 3");
+        assert!(
+            would_exceed(3),
+            "depth 3 is the afforded ceiling; depth 4 is blocked"
+        );
+    }
+
+    #[test]
+    fn exec_hardening_caps_max_steps_to_max_turns() {
+        let spec = AgentWorkerSpec {
+            worker_id: "w1".to_string(),
+            run_id: "r1".to_string(),
+            parent_run_id: None,
+            session_name: None,
+            objective: "test".to_string(),
+            role: None,
+            agent_type: SubAgentType::General,
+            model: "auto".to_string(),
+            workspace: std::path::PathBuf::from("/tmp"),
+            git_branch: None,
+            context_mode: "fresh".to_string(),
+            fork_context: false,
+            tool_profile: AgentWorkerToolProfile::Inherited,
+            max_steps: 1000,
+            spawn_depth: 0,
+            max_spawn_depth: 0,
+        };
+        let exec = codewhale_config::FleetExecConfig {
+            max_turns: 50,
+            ..Default::default()
+        };
+        let hardened = apply_exec_hardening(spec, &exec);
+        assert_eq!(hardened.max_steps, 50);
+    }
+
+    #[test]
+    fn exec_hardening_applies_and_clamps_spawn_depth() {
+        let spec = AgentWorkerSpec {
+            worker_id: "w1".to_string(),
+            run_id: "r1".to_string(),
+            parent_run_id: None,
+            session_name: None,
+            objective: "test".to_string(),
+            role: None,
+            agent_type: SubAgentType::General,
+            model: "auto".to_string(),
+            workspace: std::path::PathBuf::from("/tmp"),
+            git_branch: None,
+            context_mode: "fresh".to_string(),
+            fork_context: false,
+            tool_profile: AgentWorkerToolProfile::Inherited,
+            max_steps: 1000,
+            spawn_depth: 0,
+            max_spawn_depth: 0,
+        };
+
+        let exec = codewhale_config::FleetExecConfig {
+            max_spawn_depth: 2,
+            ..Default::default()
+        };
+        let hardened = apply_exec_hardening(spec.clone(), &exec);
+        assert_eq!(hardened.max_spawn_depth, 2);
+
+        let exec = codewhale_config::FleetExecConfig {
+            max_spawn_depth: 99,
+            ..Default::default()
+        };
+        let hardened = apply_exec_hardening(spec.clone(), &exec);
+        assert_eq!(hardened.max_spawn_depth, 3);
+
+        let exec = codewhale_config::FleetExecConfig {
+            max_spawn_depth: 0,
+            ..Default::default()
+        };
+        let hardened = apply_exec_hardening(spec, &exec);
+        assert_eq!(hardened.max_spawn_depth, 0);
+    }
+
+    #[test]
+    fn exec_hardening_filters_disallowed_tools() {
+        let profile = AgentWorkerToolProfile::Explicit(vec![
+            "read_file".to_string(),
+            "exec_shell".to_string(),
+            "git_diff".to_string(),
+        ]);
+        let exec = codewhale_config::FleetExecConfig {
+            disallowed_tools: vec!["exec_shell".to_string()],
+            ..Default::default()
+        };
+        let filtered = filter_tool_profile(&profile, &exec);
+        assert_eq!(
+            filtered,
+            AgentWorkerToolProfile::Explicit(
+                vec!["read_file".to_string(), "git_diff".to_string(),]
+            )
+        );
+    }
+
+    #[test]
+    fn exec_hardening_allowed_tools_acts_as_allowlist() {
+        let profile = AgentWorkerToolProfile::Explicit(vec![
+            "read_file".to_string(),
+            "exec_shell".to_string(),
+            "git_diff".to_string(),
+        ]);
+        let exec = codewhale_config::FleetExecConfig {
+            allowed_tools: vec!["read_file".to_string(), "git_diff".to_string()],
+            ..Default::default()
+        };
+        let filtered = filter_tool_profile(&profile, &exec);
+        assert_eq!(
+            filtered,
+            AgentWorkerToolProfile::Explicit(
+                vec!["read_file".to_string(), "git_diff".to_string(),]
+            )
+        );
+    }
+
+    #[test]
+    fn exec_hardening_allowed_plus_disallowed_disallowed_wins() {
+        let profile = AgentWorkerToolProfile::Explicit(vec![
+            "read_file".to_string(),
+            "exec_shell".to_string(),
+        ]);
+        let exec = codewhale_config::FleetExecConfig {
+            allowed_tools: vec!["read_file".to_string(), "exec_shell".to_string()],
+            disallowed_tools: vec!["exec_shell".to_string()],
+            ..Default::default()
+        };
+        let filtered = filter_tool_profile(&profile, &exec);
+        assert_eq!(
+            filtered,
+            AgentWorkerToolProfile::Explicit(vec!["read_file".to_string(),])
+        );
+    }
+
+    #[test]
+    fn parallel_safe_read_only_tools_includes_grep_and_read() {
+        assert!(is_parallel_safe_read_only_tool("read_file"));
+        assert!(is_parallel_safe_read_only_tool("grep_files"));
+        assert!(is_parallel_safe_read_only_tool("git_status"));
+        assert!(is_parallel_safe_read_only_tool("web_search"));
+    }
+
+    #[test]
+    fn destructive_tools_not_parallel_safe() {
+        assert!(!is_parallel_safe_read_only_tool("exec_shell"));
+        assert!(!is_parallel_safe_read_only_tool("write_file"));
+        assert!(!is_parallel_safe_read_only_tool("edit_file"));
+        assert!(!is_parallel_safe_read_only_tool("apply_patch"));
+        assert!(!is_parallel_safe_read_only_tool("agent_open"));
+    }
+
+    #[test]
+    fn exec_hardening_appends_system_prompt() {
+        let spec = AgentWorkerSpec {
+            worker_id: "w1".to_string(),
+            run_id: "r1".to_string(),
+            parent_run_id: None,
+            session_name: None,
+            objective: "do the thing".to_string(),
+            role: None,
+            agent_type: SubAgentType::General,
+            model: "auto".to_string(),
+            workspace: std::path::PathBuf::from("/tmp"),
+            git_branch: None,
+            context_mode: "fresh".to_string(),
+            fork_context: false,
+            tool_profile: AgentWorkerToolProfile::Inherited,
+            max_steps: 100,
+            spawn_depth: 0,
+            max_spawn_depth: 0,
+        };
+        let exec = codewhale_config::FleetExecConfig {
+            append_system_prompt: "never push to main".to_string(),
+            ..Default::default()
+        };
+        let hardened = apply_exec_hardening(spec, &exec);
+        assert!(hardened.objective.contains("do the thing"));
+        assert!(hardened.objective.contains("[Policy]"));
+        assert!(hardened.objective.contains("never push to main"));
+    }
+}
diff --git a/crates/tui/src/localization.rs b/crates/tui/src/localization.rs
index aad101df..9d203577 100644
--- a/crates/tui/src/localization.rs
+++ b/crates/tui/src/localization.rs
@@ -255,6 +255,7 @@ pub enum MessageId {
     ConfigSectionSidebar,
     ConfigSectionHistory,
     ConfigSectionMcp,
+    ConfigSectionFleet,
     ConfigSectionExperimental,
     ConfigScopeSession,
     ConfigScopeSaved,
@@ -699,6 +700,7 @@ pub const ALL_MESSAGE_IDS: &[MessageId] = &[
     MessageId::ConfigSectionSidebar,
     MessageId::ConfigSectionHistory,
     MessageId::ConfigSectionMcp,
+    MessageId::ConfigSectionFleet,
     MessageId::ConfigSectionExperimental,
     MessageId::ConfigScopeSession,
     MessageId::ConfigScopeSaved,
@@ -1315,6 +1317,7 @@ fn english(id: MessageId) -> &'static str {
         MessageId::ConfigSectionSidebar => "Sidebar",
         MessageId::ConfigSectionHistory => "History",
         MessageId::ConfigSectionMcp => "MCP",
+        MessageId::ConfigSectionFleet => "Fleet",
         MessageId::ConfigSectionExperimental => "Experimental",
         MessageId::ConfigScopeSession => "SESSION",
         MessageId::ConfigScopeSaved => "SAVED",
@@ -1915,6 +1918,7 @@ fn vietnamese(id: MessageId) -> Option<&'static str> {
         MessageId::ConfigSectionSidebar => "Thanh bên",
         MessageId::ConfigSectionHistory => "Lịch sử",
         MessageId::ConfigSectionMcp => "MCP",
+        MessageId::ConfigSectionFleet => "Fleet",
         MessageId::ConfigSectionExperimental => "Thử nghiệm",
         MessageId::ConfigScopeSession => "PHIÊN",
         MessageId::ConfigScopeSaved => "ĐÃ LƯU",
@@ -2624,6 +2628,7 @@ fn traditional_chinese(id: MessageId) -> Option<&'static str> {
         MessageId::ConfigSectionSidebar => "側邊欄",
         MessageId::ConfigSectionHistory => "歷史",
         MessageId::ConfigSectionMcp => "MCP",
+        MessageId::ConfigSectionFleet => "艦隊",
         MessageId::ConfigSectionExperimental => "實驗",
         MessageId::ConfigScopeSession => "會話",
         MessageId::ConfigScopeSaved => "已儲存",
@@ -2724,6 +2729,7 @@ fn japanese(id: MessageId) -> Option<&'static str> {
         MessageId::ConfigSectionSidebar => "サイドバー",
         MessageId::ConfigSectionHistory => "履歴",
         MessageId::ConfigSectionMcp => "MCP",
+        MessageId::ConfigSectionFleet => "Fleet",
         MessageId::ConfigSectionExperimental => "実験",
         MessageId::ConfigScopeSession => "セッション",
         MessageId::ConfigScopeSaved => "保存済み",
@@ -3315,6 +3321,7 @@ fn chinese_simplified(id: MessageId) -> Option<&'static str> {
         MessageId::ConfigSectionSidebar => "侧边栏",
         MessageId::ConfigSectionHistory => "历史",
         MessageId::ConfigSectionMcp => "MCP",
+        MessageId::ConfigSectionFleet => "舰队",
         MessageId::ConfigSectionExperimental => "实验",
         MessageId::ConfigScopeSession => "会话",
         MessageId::ConfigScopeSaved => "已保存",
@@ -3842,6 +3849,7 @@ fn portuguese_brazil(id: MessageId) -> Option<&'static str> {
         MessageId::ConfigSectionSidebar => "Barra lateral",
         MessageId::ConfigSectionHistory => "Histórico",
         MessageId::ConfigSectionMcp => "MCP",
+        MessageId::ConfigSectionFleet => "Fleet",
         MessageId::ConfigSectionExperimental => "Experimental",
         MessageId::ConfigScopeSession => "SESSÃO",
         MessageId::ConfigScopeSaved => "SALVO",
@@ -4461,6 +4469,7 @@ fn spanish_latin_america(id: MessageId) -> Option<&'static str> {
         MessageId::ConfigSectionSidebar => "Barra lateral",
         MessageId::ConfigSectionHistory => "Historial",
         MessageId::ConfigSectionMcp => "MCP",
+        MessageId::ConfigSectionFleet => "Fleet",
         MessageId::ConfigSectionExperimental => "Experimental",
         MessageId::ConfigScopeSession => "SESIÓN",
         MessageId::ConfigScopeSaved => "GUARDADO",
diff --git a/crates/tui/src/main.rs b/crates/tui/src/main.rs
index 4ba997b2..c7985e5a 100644
--- a/crates/tui/src/main.rs
+++ b/crates/tui/src/main.rs
@@ -1193,8 +1193,9 @@ async fn main() -> Result<()> {
                 run_swebench_command(&config, &model, workspace, max_subagents, args).await
             }
             Commands::Fleet(args) => {
+                let config = load_config_from_cli(&cli)?;
                 let workspace = resolve_workspace(&cli);
-                run_fleet_command(&workspace, args).await
+                run_fleet_command(&workspace, &config, args).await
             }
             Commands::Review(args) => {
                 let config = load_config_from_cli(&cli)?;
@@ -1458,7 +1459,7 @@ async fn run_swebench_command(
     }
 }
 
-async fn run_fleet_command(workspace: &Path, args: FleetArgs) -> Result<()> {
+async fn run_fleet_command(workspace: &Path, config: &Config, args: FleetArgs) -> Result<()> {
     use crate::fleet::alerts::{
         FleetAlertAdapterConfig, FleetAlertConfig, FleetAlertDispatcher, FleetAlertEvent,
         FleetEnvSecretResolver,
@@ -1712,7 +1713,12 @@ async fn run_fleet_command(workspace: &Path, args: FleetArgs) -> Result<()> {
         }
     }
 
-    let manager = FleetManager::open(workspace)?;
+    let exec_config = config
+        .fleet
+        .as_ref()
+        .map(|fleet| fleet.exec.clone())
+        .unwrap_or_default();
+    let manager = FleetManager::open(workspace)?.with_exec_config(exec_config);
     match args.command {
         FleetCommand::Init => {
             println!("fleet ledger: {}", manager.ledger_path().display());
diff --git a/crates/tui/src/runtime_api.rs b/crates/tui/src/runtime_api.rs
index 0d927099..d133bf6e 100644
--- a/crates/tui/src/runtime_api.rs
+++ b/crates/tui/src/runtime_api.rs
@@ -3980,6 +3980,7 @@ mod tests {
             crate::fleet::task_spec::FleetTaskSpecDocument {
                 name: Some("api smoke".to_string()),
                 labels: std::collections::BTreeMap::new(),
+                security_policy: None,
                 workers: Vec::new(),
                 tasks: vec![task],
             },
diff --git a/crates/tui/src/tools/subagent/mod.rs b/crates/tui/src/tools/subagent/mod.rs
index c1411fb8..c103fc88 100644
--- a/crates/tui/src/tools/subagent/mod.rs
+++ b/crates/tui/src/tools/subagent/mod.rs
@@ -1161,8 +1161,13 @@ impl Default for PersistedSubAgentState {
 }
 
 /// Default cap on sub-agent recursion depth. Override via
-/// `[runtime] max_spawn_depth = N` in `~/.deepseek/config.toml`.
-pub const DEFAULT_MAX_SPAWN_DEPTH: u32 = 3;
+/// `[runtime] max_spawn_depth = N` in config.
+///
+/// Sourced from [`codewhale_config::DEFAULT_SPAWN_DEPTH`] so standalone
+/// sub-agents and fleet workers share ONE recursion axis (no "two moving
+/// targets"). Configured/requested depths clamp to
+/// [`codewhale_config::MAX_SPAWN_DEPTH_CEILING`].
+pub const DEFAULT_MAX_SPAWN_DEPTH: u32 = codewhale_config::DEFAULT_SPAWN_DEPTH;
 
 /// Terminal-state notification emitted to the engine's parent turn loop
 /// when one of its direct children finishes (issue #756). Carries the
@@ -1794,7 +1799,7 @@ impl SubAgentManager {
             .retain(|worker_id, _| keep_ids.contains(worker_id));
     }
 
-    fn register_worker(&mut self, spec: AgentWorkerSpec) {
+    pub fn register_worker(&mut self, spec: AgentWorkerSpec) {
         let worker_id = spec.worker_id.clone();
         let now_ms = epoch_millis_now();
         let mut record = AgentWorkerRecord::new(normalize_worker_spec(spec), now_ms);
@@ -5927,15 +5932,18 @@ fn parse_spawn_request(input: &Value) -> Result<SpawnRequest, ToolError> {
         .or_else(|| input.get("max_spawn_depth"))
         .and_then(Value::as_u64)
         .map(|depth| {
+            let ceiling = codewhale_config::MAX_SPAWN_DEPTH_CEILING;
             u32::try_from(depth)
-                .map_err(|_| ToolError::invalid_input("max_depth must be between 0 and 3"))
+                .map_err(|_| {
+                    ToolError::invalid_input(format!("max_depth must be between 0 and {ceiling}"))
+                })
                 .and_then(|depth| {
-                    if depth <= 3 {
+                    if depth <= ceiling {
                         Ok(depth)
                     } else {
-                        Err(ToolError::invalid_input(
-                            "max_depth must be between 0 and 3",
-                        ))
+                        Err(ToolError::invalid_input(format!(
+                            "max_depth must be between 0 and {ceiling}"
+                        )))
                     }
                 })
         })
diff --git a/crates/tui/src/tui/views/mod.rs b/crates/tui/src/tui/views/mod.rs
index 1a4ff137..77b71083 100644
--- a/crates/tui/src/tui/views/mod.rs
+++ b/crates/tui/src/tui/views/mod.rs
@@ -412,6 +412,7 @@ enum ConfigSection {
     Sidebar,
     History,
     Mcp,
+    Fleet,
     Experimental,
 }
 
@@ -429,6 +430,7 @@ impl ConfigSection {
                 ConfigSection::Sidebar => MessageId::ConfigSectionSidebar,
                 ConfigSection::History => MessageId::ConfigSectionHistory,
                 ConfigSection::Mcp => MessageId::ConfigSectionMcp,
+                ConfigSection::Fleet => MessageId::ConfigSectionFleet,
                 ConfigSection::Experimental => MessageId::ConfigSectionExperimental,
             },
         )
@@ -759,6 +761,18 @@ impl ConfigView {
                 editable: true,
                 scope: ConfigScope::Saved,
             },
+            ConfigRow {
+                section: ConfigSection::Fleet,
+                key: "fleet.exec.max_spawn_depth".to_string(),
+                value: config
+                    .fleet
+                    .as_ref()
+                    .map(|fleet| fleet.exec.max_spawn_depth)
+                    .unwrap_or_else(|| codewhale_config::FleetExecConfig::default().max_spawn_depth)
+                    .to_string(),
+                editable: false,
+                scope: ConfigScope::Saved,
+            },
         ];
         rows.extend(experimental_config_rows(&config));
 
@@ -1180,7 +1194,7 @@ fn experimental_config_rows(config: &Config) -> Vec<ConfigRow> {
     rows.push(ConfigRow {
         section: ConfigSection::Experimental,
         key: "whaleflow".to_string(),
-        value: "preview placeholder (not stable; see #2981/#2974)".to_string(),
+        value: "preview overlay for workflow/fleet runs (not stable; see #3154/#3178)".to_string(),
         editable: false,
         scope: ConfigScope::Saved,
     });
@@ -1235,6 +1249,9 @@ fn config_hint_for_key(key: &str) -> &'static str {
             "DeepSeek: auto/off/high/max; Codex: low/medium/high/xhigh; default clears saved value"
         }
         "mcp_config_path" => "path to mcp.json",
+        "fleet.exec.max_spawn_depth" => {
+            "0 blocks child agents; 3 default (same axis as sub-agents); capped at 3"
+        }
         _ => "",
     }
 }
@@ -2393,6 +2410,7 @@ mod tests {
                 "Sidebar",
                 "History",
                 "MCP",
+                "Fleet",
                 "Experimental",
             ]
         );
@@ -2429,6 +2447,7 @@ mod tests {
         assert!(keys.contains(&"cost_currency"));
         assert!(keys.contains(&"prefer_external_pdftotext"));
         assert!(keys.contains(&"mcp_config_path"));
+        assert!(keys.contains(&"fleet.exec.max_spawn_depth"));
         assert!(keys.contains(&"features.subagents"));
         assert!(keys.contains(&"features.web_search"));
         assert!(keys.contains(&"features.apply_patch"));
@@ -2440,13 +2459,23 @@ mod tests {
         assert!(
             view.rows
                 .iter()
-                .filter(|row| row.section != super::ConfigSection::Experimental)
+                .filter(|row| {
+                    !matches!(
+                        row.section,
+                        super::ConfigSection::Experimental | super::ConfigSection::Fleet
+                    )
+                })
                 .all(|row| row.editable)
         );
         assert!(
             view.rows
                 .iter()
-                .filter(|row| row.section == super::ConfigSection::Experimental)
+                .filter(|row| {
+                    matches!(
+                        row.section,
+                        super::ConfigSection::Experimental | super::ConfigSection::Fleet
+                    )
+                })
                 .all(|row| !row.editable)
         );
     }
@@ -2497,6 +2526,36 @@ vision_model = true
         assert_eq!(subagents.value, "enabled (default enabled)");
     }
 
+    #[test]
+    fn config_view_shows_fleet_max_spawn_depth_from_config() {
+        let temp_root = std::env::temp_dir().join(format!(
+            "codewhale-fleet-config-view-test-{}",
+            std::process::id()
+        ));
+        fs::create_dir_all(&temp_root).unwrap();
+        let config_path = temp_root.join("config.toml");
+        fs::write(
+            &config_path,
+            r#"
+[fleet.exec]
+max_spawn_depth = 2
+"#,
+        )
+        .unwrap();
+
+        let mut app = create_test_app();
+        app.config_path = Some(config_path);
+        let view = ConfigView::new_for_app(&app);
+
+        let row = view
+            .rows
+            .iter()
+            .find(|row| row.key == "fleet.exec.max_spawn_depth")
+            .expect("fleet spawn depth row");
+        assert_eq!(row.value, "2");
+        assert!(!row.editable);
+    }
+
     #[test]
     fn config_view_experimental_section_is_searchable() {
         let mut view = create_config_view(Locale::En);
diff --git a/docs/FLEET.md b/docs/FLEET.md
index bc15ca76..0e33f454 100644
--- a/docs/FLEET.md
+++ b/docs/FLEET.md
@@ -19,6 +19,29 @@ Fleet state is stored under the workspace in `.codewhale/fleet.jsonl`. Worker
 logs and adapter logs are stored under `.codewhale/fleet/` and
 `.codewhale/fleet-host/`.
 
+## Naming: Modes, WhaleFlow, Fleet, and Swarm
+
+These names describe different layers, not competing systems. Agent, Plan, and
+YOLO stay the permission/work modes. WhaleFlow is an orchestration overlay that
+can run on top of those modes when the task needs a continuous workflow.
+
+- **WhaleFlow** is the repeatable workflow plan and user-facing orchestration
+  overlay: a script/IR that decides which phases and agents run next, keeps
+  intermediate results out of the main conversation, and can be inspected or
+  rerun. A WhaleFlow run should have a visible progress view and a clear active
+  header state instead of feeling like a hidden background task.
+- **Fleet** is the execution substrate: headless workers, local/SSH hosts,
+  trust policy, leases, heartbeats, logs, receipts, and status APIs.
+- **Swarm** is the high-fanout behavior inside WhaleFlow. It should compile into
+  a WhaleFlow-backed fleet run instead of reviving the old `agent_swarm` tool
+  surface.
+
+UI guidance: keep the main transcript calm. A WhaleFlow run should appear as a
+compact progress card plus Work/Agents sidebar rows with phase names, worker
+counts, receipts, and nested indentation for child workers. Use the whale mark
+sparingly as an active header/status signal; avoid repeating emoji-heavy rows
+for every worker.
+
 ## Task Spec
 
 `codewhale fleet run` accepts JSON or TOML. A minimal JSON spec:
@@ -60,118 +83,79 @@ and `json_path`. Specs may also declare `command`,
 `code_whale_verifier_prompt`, or `manual`; those record a partial receipt until
 an explicit verifier pass completes.
 
-### Release Triage Example
+### Using Role Presets
+
+Tasks can reference a role name, and the fleet manager fills in defaults
+from the role registry. Built-in roles (`smoke-runner`, `reviewer`, `builder`,
+`read-only`) are always available; define your own in `[fleet.roles]`.
 
 ```json
 {
-  "name": "v0.8.60 release triage",
-  "labels": {
-    "milestone": "v0.8.60"
-  },
+  "name": "smoke check",
   "tasks": [
     {
-      "id": "release-issue-sweep",
-      "name": "Release issue sweep",
-      "objective": "Find open v0.8.60 blockers and credit-sensitive PRs.",
-      "instructions": "Review the v0.8.60 milestone, linked PRs, changelog entries, and contributor-credit requirements. Write a concise blocker report.",
-      "worker": {
-        "role": "release-triage",
-        "tool_profile": "read-only",
-        "tools": ["gh", "git"],
-        "capabilities": ["github", "release"]
-      },
-      "workspace": {
-        "required_files": ["Cargo.toml", "CHANGELOG.md", ".github/AUTHOR_MAP"],
-        "writable_paths": [".codewhale/fleet"],
-        "environment": {
-          "required": ["PATH"]
-        }
-      },
-      "input_files": ["CHANGELOG.md", ".github/AUTHOR_MAP"],
-      "context": ["Treat community PRs as maintainer evidence."],
-      "budget": {
-        "max_tokens": 12000,
-        "max_tool_calls": 24,
-        "max_seconds": 900
-      },
-      "timeout_seconds": 900,
-      "expected_artifacts": ["log", "report", "receipt"],
-      "scorer": {
-        "kind": "exit_code"
-      },
-      "retry_policy": {
-        "max_attempts": 2,
-        "initial_backoff_seconds": 10,
-        "max_backoff_seconds": 60,
-        "backoff_multiplier": 2
-      },
-      "tags": ["release", "triage"],
-      "metadata": {
-        "class": "release"
-      }
+      "id": "lint",
+      "name": "Lint check",
+      "instructions": "Run lint and report failures.",
+      "worker": { "role": "smoke-runner" },
+      "expected_artifacts": ["log"]
     }
   ]
 }
 ```
 
-### Code Review Swarm Example
+The task inherits the role's tool profile, budget, and timeout. You can
+override any field in the task spec:
 
 ```json
 {
-  "name": "code review swarm",
+  "id": "deep-review",
+  "name": "Deep review",
+  "instructions": "Review the entire crate for soundness issues.",
+  "worker": {
+    "role": "reviewer",
+    "tools": ["cargo", "rg", "git"],
+    "capabilities": ["rust"]
+  },
+  "input_files": ["crates/**/*.rs"],
+  "budget": { "max_tokens": 32000 },
+  "expected_artifacts": ["log", "report"],
+  "scorer": { "kind": "regex_match", "path": ".codewhale/fleet/report.md", "pattern": "finding|all clear" }
+}
+```
+
+### Multi-Task Run Example
+
+A single fleet run can dispatch several independent tasks in parallel:
+
+```json
+{
+  "name": "CI gate",
   "tasks": [
     {
-      "id": "protocol-review",
-      "name": "Protocol review",
-      "objective": "Review fleet protocol changes for compatibility and sparse JSON behavior.",
-      "instructions": "Inspect crates/protocol/src/fleet.rs and report behavior regressions, missing serde defaults, or unsafe wire changes.",
-      "worker": {
-        "role": "reviewer",
-        "tool_profile": "read-only",
-        "tools": ["git", "rg", "cargo"],
-        "capabilities": ["rust"]
-      },
-      "input_files": ["crates/protocol/src/fleet.rs"],
-      "budget": {
-        "max_tokens": 8000,
-        "max_tool_calls": 16,
-        "max_seconds": 600
-      },
-      "expected_artifacts": ["log", "report", "receipt"],
-      "scorer": {
-        "kind": "code_whale_verifier_prompt",
-        "prompt": "Verify the review includes at least one concrete file:line finding or explicitly says no issues were found."
-      },
-      "tags": ["review", "protocol"],
-      "metadata": {
-        "class": "code-review"
-      }
+      "id": "check",
+      "name": "Compile check",
+      "instructions": "Run cargo check --workspace and report errors.",
+      "worker": { "role": "builder" },
+      "expected_artifacts": ["log"],
+      "scorer": { "kind": "exit_code" }
     },
     {
-      "id": "tui-review",
-      "name": "TUI review",
-      "objective": "Review fleet CLI and manager behavior for operator-visible regressions.",
-      "instructions": "Inspect crates/tui/src/fleet and crates/tui/src/main.rs. Focus on status output, receipt recording, and failure classification.",
-      "worker": {
-        "role": "reviewer",
-        "tool_profile": "read-only",
-        "tools": ["git", "rg", "cargo"],
-        "capabilities": ["rust", "cli"]
-      },
-      "input_files": ["crates/tui/src/fleet", "crates/tui/src/main.rs"],
-      "budget": {
-        "max_tokens": 10000,
-        "max_tool_calls": 20,
-        "max_seconds": 600
-      },
-      "expected_artifacts": ["log", "report", "receipt"],
-      "scorer": {
-        "kind": "manual"
-      },
-      "tags": ["review", "tui"],
-      "metadata": {
-        "class": "code-review"
-      }
+      "id": "clippy",
+      "name": "Clippy lint",
+      "instructions": "Run cargo clippy --workspace and report warnings.",
+      "worker": { "role": "reviewer", "tools": ["cargo", "cargo-clippy"] },
+      "expected_artifacts": ["log"],
+      "scorer": { "kind": "exit_code" }
+    },
+    {
+      "id": "security",
+      "name": "Secret audit",
+      "instructions": "Search for plaintext secrets and report any matches.",
+      "worker": { "role": "read-only", "tools": ["rg"] },
+      "input_files": ["crates/**/*.rs"],
+      "expected_artifacts": ["log", "report"],
+      "retry_policy": { "max_attempts": 1 }
     }
   ]
 }
@@ -373,3 +357,168 @@ Defaults are intentionally conservative:
   `API_KEY`, and `PRIVATE_KEY` are rejected from adapter allowlists;
 - secrets should remain in CodeWhale config providers or remote host config,
   not in task instructions, argv, or fleet logs.
+
+## Security and Trust Boundaries
+
+Agent Fleet enforces a trust-level model that separates workers into four tiers.
+The trust level determines what a worker can access (secrets, network, workspace
+writes) and how it must prove its identity before being granted those privileges.
+
+### Trust Levels
+
+| Level | Access | Requires |
+|-------|--------|----------|
+| `sandbox` | No network, no secrets, writes only to `.codewhale/fleet/` | Nothing — default for new workers |
+| `local` | Workspace reads, gated writes, configured secrets | Local process (same uid) |
+| `remote-verified` | Network access, bounded capability grants, configured secrets | SSH host-key verification or equivalent attestation |
+| `operator` | Full access to all secrets, unrestricted writes, any action | Operator-owned machine |
+
+The default trust level is `sandbox`. Operators must explicitly raise trust for
+SSH or container workers through the security policy.
+
+### Security Policy
+
+A fleet run may carry an optional `security_policy` block that defines the
+default trust level, which secrets workers may resolve, what capabilities are
+granted, and a ceiling on the maximum trust level:
+
+```json
+{
+  "security_policy": {
+    "default_trust_level": "sandbox",
+    "allowed_secrets": [
+      {"key": "GH_TOKEN", "source": "env"},
+      {"key": "CODEWHALE_API_KEY", "source": "keyring"}
+    ],
+    "capability_grants": [
+      {
+        "capability": "network",
+        "scope": "github.com",
+        "reason": "PR review needs GitHub API access"
+      }
+    ],
+    "max_trust_level": "remote_verified",
+    "require_identity_verification": true
+  }
+}
+```
+
+When a run has no explicit `security_policy`, workers inherit conservative
+defaults: `sandbox` trust, no secrets, no capability grants, and no identity
+verification requirement.
+
+### Secret References
+
+Secrets are never stored as plaintext in task specs, alert configs, or worker
+definitions. Instead, every secret is a `FleetSecretRef` — a key name plus an
+optional source hint that tells the fleet manager where to resolve the value:
+
+```json
+{"key": "GH_TOKEN", "source": "env"}
+```
+
+Supported sources:
+- `"env"` — resolve from a process environment variable
+- `"keyring"` — resolve from the OS keyring (macOS Keychain, Windows Credential Manager, Linux Secret Service)
+- `"file"` — resolve from `~/.codewhale/secrets/`
+- absent — try all sources in default order (store first, then env)
+
+Secret refs are redacted in logs and ledger entries: `<secret:env.GH_TOKEN>`.
+
+### Worker Authentication
+
+Workers authenticate to the fleet manager using one of three methods:
+
+- **None** — local workers sharing the same uid (default)
+- **SSH key** — with optional host-key fingerprint pinning and known-hosts
+  verification. The `host_key_fingerprint` field (SHA256:...) pins the expected
+  server key, preventing MITM attacks on first connection.
+- **Token** — a bearer token resolved from a `FleetSecretRef`, useful for remote
+  workers behind a fleet proxy.
+- **mTLS** — mutual TLS with a client certificate and a secret-backed private key.
+
+SSH workers should always set `host_key_fingerprint` in production:
+
+```json
+{
+  "id": "builder-1",
+  "name": "Builder 1",
+  "trust_level": "remote_verified",
+  "host": {
+    "kind": "ssh",
+    "host": "builder.example.com",
+    "user": "codewhale",
+    "port": 22,
+    "identity": "~/.ssh/codewhale_fleet",
+    "host_key_fingerprint": "SHA256:aLGqZo1M6c...",
+    "known_hosts": "~/.ssh/known_hosts",
+    "working_directory": "/srv/codewhale/work",
+    "env_allowlist": ["CODEWHALE_PROFILE"],
+    "codewhale_binary": "/usr/local/bin/codewhale"
+  },
+  "capabilities": ["local", "linux", "tests"],
+  "max_concurrent_tasks": 1
+}
+```
+
+### Alert Channel Secrets
+
+Alert channels (Slack, generic webhook, PagerDuty) use `FleetAlertEndpoint`
+instead of raw URLs. The webhook URL can be provided inline for non-sensitive
+endpoints, or as a secret reference:
+
+```json
+{
+  "kind": "slack",
+  "webhook": {
+    "url_ref": {"key": "CODEWHALE_FLEET_SLACK_WEBHOOK", "source": "env"},
+    "secret_ref": {"key": "CODEWHALE_FLEET_SLACK_SIGNING_SECRET", "source": "keyring"}
+  }
+}
+```
+
+The `secret_ref` field provides an optional HMAC secret for webhook payload
+signing, never stored in plaintext.
+
+### Config File
+
+The `[fleet]` table in `config.toml` sets global trust policy defaults:
+
+```toml
+[fleet]
+default_trust_level = "sandbox"
+require_identity_verification = true
+max_trust_level = "operator"
+
+[fleet.exec]
+# Recursion depth shares ONE axis with standalone sub-agents — a fleet worker
+# IS a headless sub-agent. 0 blocks child agents (the root worker still runs);
+# 3 is the default and the ceiling, affording at least three nested levels.
+max_spawn_depth = 3
+```
+
+These defaults apply to fleet runs that don't carry their own `security_policy`.
+Per-run policies always override the config defaults.
+
+### Capability Grants
+
+Capability grants are additive, scoped permissions that authorize specific
+actions. By default, workers get no grants (least privilege). Common grants:
+
+- `"network"` with scope `"github.com"` — allow outbound HTTP to GitHub
+- `"git-push"` — allow `git push` to remotes
+- `"provider-secrets"` — allow accessing provider API keys
+- `"release"` — allow release-related operations (tagging, publishing)
+- `"workspace-write"` with scope `"crates/tui/**"` — allow writes within a path
+
+### Environment Sanitization
+
+The host adapter layer enforces environment sanitization at worker start:
+
+- Only `HOME`, `PATH`, and platform-specific vars (`SYSTEMROOT`, `COMSPEC`) are
+  injected into worker processes by default
+- Environment allowlists reject any key containing `SECRET`, `TOKEN`, `PASSWORD`,
+  `PASSWD`, `API_KEY`, `CREDENTIAL`, or `PRIVATE_KEY`
+- SSH workers only send explicitly allowlisted variables via OpenSSH `SendEnv`
+- Secret values are never embedded in worker argv, task instructions, or fleet
+  logs — only secret refs appear, and they are always redacted
diff --git a/docs/MODES.md b/docs/MODES.md
index c5e823e9..d4381dd1 100644
--- a/docs/MODES.md
+++ b/docs/MODES.md
@@ -4,11 +4,18 @@ codewhale has two related concepts:
 
 - **TUI mode**: what kind of visible interaction you're in (Plan/Agent/YOLO).
 - **Approval mode**: how aggressively the UI asks before executing tools.
+- **WhaleFlow overlay**: optional long-running workflow orchestration that can
+  run on top of any TUI mode when a task needs many coordinated workers.
 
 Model selection is separate. `--model auto` and `/model auto` route each turn to
 a concrete model and thinking level; they are not TUI modes and are not part of
 the `Tab` cycle.
 
+WhaleFlow is also separate from the `Tab` mode cycle. It is the visible
+continuous-work layer for repeatable workflows, fleet workers, and swarm-style
+fanout. The active mode still controls permissions; WhaleFlow controls whether a
+large task is planned into a resumable workflow with its own progress view.
+
 Each user turn includes a small `<turn_meta>` block with the current local date
 and the concrete model sent to the provider. When `--model auto` is active, the
 same block also records that the model was auto-routed.
@@ -56,6 +63,11 @@ the turn, `/goal complete` marks it done, `/goal blocked` marks it blocked, and
 approval mode, or model route. This remains distinct from `--model auto`, which
 only controls model and thinking selection.
 
+WhaleFlow builds on the same separation: a goal can ask the agent to keep
+working, while WhaleFlow supplies the repeatable workflow/progress surface for
+large fanout. In the UI, a WhaleFlow run should be shown as an overlay on the
+main screen, not as a fourth mode next to Agent, Plan, and YOLO.
+
 App-server clients can persist a thread-scoped goal with `thread/goal/set`, read
 it with `thread/goal/get`, and clear it with `thread/goal/clear`. That persisted
 record carries `active`, `paused`, `blocked`, `usage_limited`, `budget_limited`,
diff --git a/docs/examples/fleet-dogfood.toml b/docs/examples/fleet-dogfood.toml
new file mode 100644
index 00000000..14e9e047
--- /dev/null
+++ b/docs/examples/fleet-dogfood.toml
@@ -0,0 +1,52 @@
+# Agent Fleet dogfood smoke spec (#3166)
+#
+# This spec exercises the fleet end-to-end: create a run with two local
+# workers, run a lint task and a review task, verify the ledger records
+# receipts, and confirm the status surfaces work.
+#
+# Run:
+#   codewhale fleet run docs/examples/fleet-dogfood.toml --max-workers 2 --once
+#
+# Then check:
+#   codewhale fleet status
+#   codewhale fleet inspect <worker-id-from-status>
+#   codewhale fleet logs <worker-id-from-status>
+
+name = "dogfood smoke"
+labels = { milestone = "v0.8.60", class = "smoke" }
+
+security_policy = { default_trust_level = "local", allowed_secrets = [], require_identity_verification = false }
+
+[[tasks]]
+id = "cargo-check"
+name = "Workspace check"
+description = "Run `cargo check --workspace` and report any compilation errors."
+objective = "Verify the workspace compiles cleanly with zero errors."
+instructions = "Run `cargo check --workspace` in the repo root. If it compiles cleanly, report success. If there are errors, list each file:line and the error message. Do NOT attempt to fix anything — just report what you found."
+worker = { role = "release-checker", tool_profile = "read-only", tools = ["cargo"], capabilities = ["rust"] }
+workspace = { required_files = ["Cargo.toml"], writable_paths = [".codewhale/fleet"], environment = { required = ["PATH"] } }
+input_files = ["Cargo.toml"]
+context = ["You are running in a fleet smoke test. Be concise. Only report the pass/fail and any specific errors."]
+budget = { max_tokens = 8000, max_tool_calls = 12, max_seconds = 300 }
+expected_artifacts = ["log", "report", "receipt"]
+scorer = { kind = "exit_code" }
+retry_policy = { max_attempts = 2, initial_backoff_seconds = 5, max_backoff_seconds = 30 }
+timeout_seconds = 300
+tags = ["smoke", "check"]
+
+[[tasks]]
+id = "protocol-review"
+name = "Protocol review"
+description = "Review fleet protocol types for security and correctness."
+objective = "Inspect crates/protocol/src/fleet.rs and crates/secrets/src/lib.rs. Report any missing serde defaults, unsafe wire changes, or security-sensitive fields lacking SecretRef."
+instructions = "Read crates/protocol/src/fleet.rs and crates/secrets/src/lib.rs. Check for: (1) new fields without serde(default) or skip_serializing_if, (2) raw secrets in struct fields instead of FleetSecretRef, (3) missing Clone/Debug/PartialEq derives on new types. Write a concise report with file:line references for each finding. If there are no findings, report 'all clear'."
+worker = { role = "reviewer", tool_profile = "read-only", tools = ["rg", "git", "cargo"], capabilities = ["rust"] }
+workspace = { required_files = ["crates/protocol/src/fleet.rs", "crates/secrets/src/lib.rs"], writable_paths = [".codewhale/fleet"], environment = { required = ["PATH"] } }
+input_files = ["crates/protocol/src/fleet.rs", "crates/secrets/src/lib.rs"]
+context = ["You are a fleet protocol reviewer. Be thorough but concise. Reference specific lines."]
+budget = { max_tokens = 10000, max_tool_calls = 16, max_seconds = 600 }
+expected_artifacts = ["log", "report", "receipt"]
+scorer = { kind = "code_whale_verifier_prompt", prompt = "Verify the review includes at least one concrete file:line finding or explicitly says 'all clear'." }
+retry_policy = { max_attempts = 1, initial_backoff_seconds = 10 }
+timeout_seconds = 600
+tags = ["smoke", "review", "protocol"]