diff --git a/docs/PROVIDERS.md b/docs/PROVIDERS.md
index ec9657ab..2899b980 100644
--- a/docs/PROVIDERS.md
+++ b/docs/PROVIDERS.md
@@ -22,7 +22,8 @@ Sources to keep in sync:
 - `config.example.toml` and `docs/CONFIGURATION.md` - user-facing config
   examples and environment variable reference.
 - `scripts/check-provider-registry.py` - drift check for canonical provider
-  IDs, TOML table names, static registry rows, and documented defaults.
+  IDs, live TUI provider IDs, TOML table names, static registry rows, and
+  documented defaults.
 
 ## Provider Selection
 
@@ -147,6 +148,8 @@ python3 scripts/check-provider-registry.py
 The check fails when:
 
 - `docs/PROVIDERS.md` omits a canonical `ProviderKind::as_str()` ID.
+- `crates/tui/src/config.rs` `ApiProvider::as_str()` diverges from
+  `ProviderKind::as_str()` except for the explicit `deepseek-cn` legacy alias.
 - The shipped-provider table omits or adds a `[providers.*]` TOML table.
 - The static model registry table drifts from providers used by
   `crates/agent/src/lib.rs`.
diff --git a/scripts/check-provider-registry.py b/scripts/check-provider-registry.py
index ebc1d556..ed6b28b8 100644
--- a/scripts/check-provider-registry.py
+++ b/scripts/check-provider-registry.py
@@ -6,6 +6,7 @@ the stable identifiers and default strings that are easy for docs to drift from:
 
 - canonical ProviderKind IDs
 - provider TOML tables
+- live TUI ApiProvider IDs
 - shipped-provider table rows
 - static ModelRegistry provider rows
 - default provider model/base URL constants
@@ -24,6 +25,10 @@ TUI_CONFIG_RS = ROOT / "crates" / "tui" / "src" / "config.rs"
 AGENT_RS = ROOT / "crates" / "agent" / "src" / "lib.rs"
 PROVIDERS_MD = ROOT / "docs" / "PROVIDERS.md"
 
+
+API_PROVIDER_ONLY_IDS = {"deepseek-cn"}
+
+
 def read(path: Path) -> str:
     return path.read_text(encoding="utf-8")
 
@@ -42,8 +47,10 @@ def markdown_section(source: str, heading: str) -> str:
     return source[start:end]
 
 
-def extract_match_block(source: str, signature: str) -> str:
-    start = require_index(source, signature, "crates/config/src/lib.rs")
+def extract_match_block(
+    source: str, signature: str, context: str, start: int = 0
+) -> str:
+    start = require_index(source, signature, context, start)
     match_start = require_index(source, "match", f"match block after {signature!r}", start)
     brace_start = require_index(source, "{", f"match block after {signature!r}", match_start)
     depth = 0
@@ -59,13 +66,37 @@ def extract_match_block(source: str, signature: str) -> str:
 
 
 def provider_kind_ids(config_rs: str) -> dict[str, str]:
-    block = extract_match_block(config_rs, "pub fn as_str(self) -> &'static str")
+    impl_start = require_index(
+        config_rs, "impl ProviderKind", "crates/config/src/lib.rs"
+    )
+    block = extract_match_block(
+        config_rs,
+        "pub fn as_str(self) -> &'static str",
+        "crates/config/src/lib.rs",
+        impl_start,
+    )
     pairs = re.findall(r"Self::(\w+)\s*=>\s*\"([^\"]+)\"", block)
     if not pairs:
         raise ValueError("ProviderKind::as_str returned no providers")
     return {variant: provider_id for variant, provider_id in pairs}
 
 
+def api_provider_ids(tui_config_rs: str) -> dict[str, str]:
+    impl_start = require_index(
+        tui_config_rs, "impl ApiProvider", "crates/tui/src/config.rs"
+    )
+    block = extract_match_block(
+        tui_config_rs,
+        "pub fn as_str(self) -> &'static str",
+        "crates/tui/src/config.rs",
+        impl_start,
+    )
+    pairs = re.findall(r"Self::(\w+)\s*=>\s*\"([^\"]+)\"", block)
+    if not pairs:
+        raise ValueError("ApiProvider::as_str returned no providers")
+    return {variant: provider_id for variant, provider_id in pairs}
+
+
 def provider_tables(config_rs: str) -> set[str]:
     struct_start = require_index(
         config_rs, "pub struct ProvidersToml", "crates/config/src/lib.rs"
@@ -133,6 +164,34 @@ def report_set(label: str, expected: set[str], actual: set[str]) -> list[str]:
     return errors
 
 
+def report_provider_enum_drift(
+    provider_kind_ids: set[str], api_provider_ids: set[str]
+) -> list[str]:
+    errors = []
+    missing_from_api_provider = sorted(provider_kind_ids - api_provider_ids)
+    unexpected_api_provider_ids = sorted(
+        api_provider_ids - provider_kind_ids - API_PROVIDER_ONLY_IDS
+    )
+    missing_allowlisted_ids = sorted(API_PROVIDER_ONLY_IDS - api_provider_ids)
+
+    if missing_from_api_provider:
+        errors.append(
+            "ApiProvider missing ProviderKind IDs: "
+            + ", ".join(missing_from_api_provider)
+        )
+    if unexpected_api_provider_ids:
+        errors.append(
+            "ApiProvider has non-whitelisted IDs absent from ProviderKind: "
+            + ", ".join(unexpected_api_provider_ids)
+        )
+    if missing_allowlisted_ids:
+        errors.append(
+            "ApiProvider-only whitelist entries are absent from ApiProvider: "
+            + ", ".join(missing_allowlisted_ids)
+        )
+    return errors
+
+
 def main() -> int:
     try:
         config_rs = read(CONFIG_RS)
@@ -142,9 +201,11 @@ def main() -> int:
 
         variant_to_id = provider_kind_ids(config_rs)
         canonical_ids = set(variant_to_id.values())
+        live_api_provider_ids = set(api_provider_ids(tui_config_rs).values())
         expected_tables = {provider_id.replace("-", "_") for provider_id in canonical_ids}
 
         errors: list[str] = []
+        errors += report_provider_enum_drift(canonical_ids, live_api_provider_ids)
         errors += report_set(
             "shipped provider rows",
             canonical_ids,