fix(anthropic_wif): let deployment token refs beat the env identity source kind and surface signing ImportError detail

litellm/llms/anthropic/wif.py

@@ -54,6 +54,8 @@ _DEFAULT_TRUSTED_EXCHANGE_HOST: Final = "api.anthropic.com"
 _REJECTED_REF_PREFIX: Final = "oidc/env_path/"
 _IDENTITY_SOURCE_PARAM: Final = "anthropic_identity_source"
 _IDENTITY_SOURCE_ENV: Final = "ANTHROPIC_IDENTITY_SOURCE"
+_IDENTITY_TOKEN_FILE_PARAM: Final = "anthropic_identity_token_file"
+_IDENTITY_TOKEN_PARAM: Final = "anthropic_identity_token"
 
 # litellm_params key -> InternalIssuerSource/KeycloakSource field name. Every key here must
 # also be listed in ANTHROPIC_WIF_KWARGS_KEYS (get_litellm_params.py), which is what makes it
@@ -136,8 +138,10 @@ def _resolve_identity_source(
     frozen config, hashes it into the ``oidc/<kind>/<hash>`` cache-key ref (``identity_source_ref``),
     and closes the source's fetch/mint function over it. An unset-but-invalid config (unknown
     kind, a missing required field, or a field from the other variant) fails closed here rather
-    than silently falling back to token_file."""
-    source_kind: Final = _config_value(litellm_params, _IDENTITY_SOURCE_PARAM, _IDENTITY_SOURCE_ENV)
+    than silently falling back to token_file. A deployment whose params carry a legacy token or
+    token_file ref stays on legacy resolution even when ``ANTHROPIC_IDENTITY_SOURCE`` names a
+    fleet-wide kind: the env kind only governs deployments that set no identity params of their own."""
+    source_kind: Final = _resolve_source_kind(litellm_params)
     if source_kind is None:
         legacy_ref: Final = _resolve_assertion_ref(litellm_params)
         return (legacy_ref, None) if legacy_ref is not None else None
@@ -166,6 +170,16 @@ def _resolve_identity_source(
             )
 
 
+def _resolve_source_kind(litellm_params: Mapping[str, object] | None) -> str | None:
+    param_kind: Final = _param_str(litellm_params, _IDENTITY_SOURCE_PARAM)
+    if param_kind is not None:
+        return param_kind
+    has_param_legacy_ref: Final = any(
+        _param_str(litellm_params, key) is not None for key in (_IDENTITY_TOKEN_FILE_PARAM, _IDENTITY_TOKEN_PARAM)
+    )
+    return None if has_param_legacy_ref else _env_str(_IDENTITY_SOURCE_ENV)
+
+
 def _reject_foreign_variant_fields(
     litellm_params: Mapping[str, object], foreign_field_map: Mapping[str, str], chosen_kind: str
 ) -> None:
@@ -360,10 +374,10 @@ def _env_str(name: str) -> str | None:
 
 
 def _resolve_assertion_ref(litellm_params: Mapping[str, object] | None) -> str | None:
-    file_param: Final = _param_str(litellm_params, "anthropic_identity_token_file")
+    file_param: Final = _param_str(litellm_params, _IDENTITY_TOKEN_FILE_PARAM)
     if file_param is not None:
         return f"oidc/file/{file_param}"
-    inline_param: Final = _param_str(litellm_params, "anthropic_identity_token")
+    inline_param: Final = _param_str(litellm_params, _IDENTITY_TOKEN_PARAM)
     if inline_param is not None:
         return _validated_inline_ref(inline_param)
     file_env: Final = _env_str("ANTHROPIC_IDENTITY_TOKEN_FILE")

litellm/llms/base_llm/auth/token_exchange.py

@@ -305,7 +305,7 @@ def _read_assertion(fetch: AssertionSource, ref: str) -> SecretStr | AssertionSo
         raw: Final = fetch()
     except OidcPathNotAllowedError:
         return AssertionSourceError(kind="disallowed_path", source_ref=ref)
-    except ValueError as e:
+    except (ValueError, ImportError) as e:
         return AssertionSourceError(kind="unreadable", source_ref=ref, detail=str(e)[:_REDACTION_CAP])
     except Exception:  # noqa: BLE001  # injected readers (secret managers) raise arbitrarily; all failures become values
         return AssertionSourceError(kind="unreadable", source_ref=ref)

tests/test_litellm/llms/anthropic/test_anthropic_wif.py

@@ -436,6 +436,55 @@ class TestResolutionMatrix:
         assert params is not None
         assert params.assertion_ref == "oidc/file//var/run/secrets/env-tok"
 
+    def test_param_token_ref_beats_env_identity_source(self, monkeypatch: pytest.MonkeyPatch):
+        monkeypatch.setenv("ANTHROPIC_IDENTITY_SOURCE", "internal_issuer")
+        params = resolve_anthropic_wif_params(
+            {
+                "anthropic_federation_rule_id": "fdrl_1",
+                "anthropic_organization_id": "org-1",
+                "anthropic_identity_token_file": "/var/run/secrets/dep-tok",
+            }
+        )
+        assert params is not None
+        assert params.assertion_ref == "oidc/file//var/run/secrets/dep-tok"
+        assert params.assertion_source is None
+
+    def test_param_inline_token_beats_env_identity_source(self, monkeypatch: pytest.MonkeyPatch):
+        monkeypatch.setenv("ANTHROPIC_IDENTITY_SOURCE", "internal_issuer")
+        params = resolve_anthropic_wif_params(
+            {
+                "anthropic_federation_rule_id": "fdrl_1",
+                "anthropic_organization_id": "org-1",
+                "anthropic_identity_token": "oidc/env/OTHER",
+            }
+        )
+        assert params is not None
+        assert params.assertion_ref == "oidc/env/OTHER"
+        assert params.assertion_source is None
+
+    def test_env_identity_source_beats_env_token_refs(self, monkeypatch: pytest.MonkeyPatch):
+        monkeypatch.setenv("ANTHROPIC_IDENTITY_SOURCE", "internal_issuer")
+        monkeypatch.setenv("ANTHROPIC_IDENTITY_TOKEN_FILE", "/var/run/secrets/env-tok")
+        with pytest.raises(litellm.AuthenticationError):
+            resolve_anthropic_wif_params(
+                {"anthropic_federation_rule_id": "fdrl_1", "anthropic_organization_id": "org-1"}
+            )
+
+    def test_env_identity_source_dispatches_param_issuer_fields(self, monkeypatch: pytest.MonkeyPatch):
+        monkeypatch.setenv("ANTHROPIC_IDENTITY_SOURCE", "internal_issuer")
+        params = resolve_anthropic_wif_params(
+            {
+                "anthropic_federation_rule_id": "fdrl_1",
+                "anthropic_organization_id": "org-1",
+                "anthropic_issuer_url": "https://issuer.internal.example",
+                "anthropic_issuer_subject": "workload-a",
+                "anthropic_issuer_signing_key_ref": ISSUER_SIGNING_KEY_REF,
+            }
+        )
+        assert params is not None
+        assert params.assertion_ref.startswith("oidc/internal_issuer/")
+        assert params.assertion_source is not None
+
     def test_empty_workspace_env_coerced_to_none(self, monkeypatch: pytest.MonkeyPatch):
         monkeypatch.setenv("ANTHROPIC_WORKSPACE_ID", "")
         params = resolve_anthropic_wif_params(

tests/test_litellm/llms/base_llm/auth/test_token_exchange.py

@@ -840,6 +840,7 @@ class TestAssertionGuards:
         [
             (OidcPathNotAllowedError("path outside allowed credential directories"), "disallowed_path"),
             (ValueError("Environment variable ANTHROPIC_IDENTITY_TOKEN not found"), "unreadable"),
+            (ImportError("needs PyJWT and cryptography: pip install 'litellm[proxy]'"), "unreadable"),
             (OSError("permission denied"), "unreadable"),
         ],
     )
@@ -866,6 +867,18 @@ class TestAssertionGuards:
         assert isinstance(result, AssertionSourceError)
         assert result.detail == "Keycloak token endpoint returned invalid_client"
 
+    def test_import_error_message_is_captured_as_detail(self):
+        poster = ScriptedPoster([token_response()])
+
+        def reader(ref: str) -> str | None:
+            raise ImportError("the internal_issuer identity source needs PyJWT and cryptography: pip install 'litellm[proxy]'")
+
+        result = make_engine(poster, reader=reader).get_token(make_spec())
+
+        assert isinstance(result, AssertionSourceError)
+        assert result.detail is not None
+        assert "litellm[proxy]" in result.detail
+
     @pytest.mark.parametrize(
         "raised",
         [OidcPathNotAllowedError("path outside allowed credential directories"), OSError("permission denied")],