diff --git a/containers/api-proxy/oidc-adapter-utils.js b/containers/api-proxy/oidc-adapter-utils.js
index e26f7939a..c92f23acd 100644
--- a/containers/api-proxy/oidc-adapter-utils.js
+++ b/containers/api-proxy/oidc-adapter-utils.js
@@ -88,9 +88,34 @@ function resolveOidcAuthHeaders({ oidcProvider, awsOidcProvider, buildOidcHeader
   return null;
 }
 
+/**
+ * Resolve auth headers with automatic static-key fallback.
+ *
+ * Combines OIDC resolution with a static-key fallback into a single call,
+ * encapsulating the repeated pattern across provider adapters:
+ *   1. If OIDC provider has a token → use buildOidcHeaders(token)
+ *   2. If OIDC is configured but no token yet → return empty {} (fail-safe)
+ *   3. If no OIDC → return staticHeaders
+ *
+ * @param {object} opts
+ * @param {{ getToken: () => (string|undefined|null) }|null|undefined} [opts.oidcProvider]
+ * @param {unknown} [opts.awsOidcProvider]
+ * @param {(token: string) => Record<string, string>} opts.buildOidcHeaders
+ * @param {Record<string, string>} opts.staticHeaders - Headers to use when no OIDC is configured
+ * @returns {Record<string, string>}
+ */
+function resolveAuthHeadersWithFallback({ oidcProvider, awsOidcProvider, buildOidcHeaders, staticHeaders }) {
+  const oidcHeaders = resolveOidcAuthHeaders({ oidcProvider, awsOidcProvider, buildOidcHeaders });
+  if (oidcHeaders !== null) {
+    return oidcHeaders;
+  }
+  return staticHeaders;
+}
+
 module.exports = {
   isValidHeaderName,
   validateAuthHeaderEnv,
   createOidcRuntimeAdapterMethods,
   resolveOidcAuthHeaders,
+  resolveAuthHeadersWithFallback,
 };
diff --git a/containers/api-proxy/providers/anthropic.js b/containers/api-proxy/providers/anthropic.js
index 1d3ce4282..539b6f93c 100644
--- a/containers/api-proxy/providers/anthropic.js
+++ b/containers/api-proxy/providers/anthropic.js
@@ -20,6 +20,7 @@ const {
 const {
   validateAuthHeaderEnv,
   resolveOidcAuthHeaders,
+  resolveAuthHeadersWithFallback,
 } = require('../oidc-adapter-utils');
 const { createBaseAdapterConfig, createAdapterMethods, buildProviderAdapter } = require('../adapter-factory');
 const { AnthropicOidcTokenProvider } = require('../anthropic-oidc-token-provider');
@@ -127,20 +128,16 @@ function createAnthropicAdapter(env, deps = {}) {
     validationPath: '/v1/messages',
     validationMethod: 'POST',
     validationBody: '{}',
-    validationHeaders: () => {
-      if (oidcProvider && oidcProvider.isReady()) {
-        return {
-          'Authorization': `Bearer ${oidcProvider.getToken()}`,
-          'anthropic-version': '2023-06-01',
-          'content-type': 'application/json',
-        };
-      }
-      return {
-        [authHeaderName]: apiKey,
-        'anthropic-version': '2023-06-01',
-        'content-type': 'application/json',
-      };
-    },
+    validationHeaders: () => ({
+      ...resolveAuthHeadersWithFallback({
+        oidcProvider,
+        awsOidcProvider: null,
+        buildOidcHeaders: (token) => ({ 'Authorization': `Bearer ${token}` }),
+        staticHeaders: { [authHeaderName]: apiKey },
+      }),
+      'anthropic-version': '2023-06-01',
+      'content-type': 'application/json',
+    }),
     validationSkip: () => {
       if (!oidcConfigured) return null;
       // After OIDC init, validate using the acquired token
@@ -149,12 +146,15 @@ function createAnthropicAdapter(env, deps = {}) {
     },
     skipModelsFetch: () => oidcConfigured && !oidcProvider?.isReady(),
     modelsPath: '/v1/models',
-    modelsFetchHeaders: () => {
-      if (oidcProvider && oidcProvider.isReady()) {
-        return { 'Authorization': `Bearer ${oidcProvider.getToken()}`, 'anthropic-version': '2023-06-01' };
-      }
-      return { [authHeaderName]: apiKey, 'anthropic-version': '2023-06-01' };
-    },
+    modelsFetchHeaders: () => ({
+      ...resolveAuthHeadersWithFallback({
+        oidcProvider,
+        awsOidcProvider: null,
+        buildOidcHeaders: (token) => ({ 'Authorization': `Bearer ${token}` }),
+        staticHeaders: { [authHeaderName]: apiKey },
+      }),
+      'anthropic-version': '2023-06-01',
+    }),
     reflectionConfigured: !!apiKey || oidcRequested,
     reflectionExtra: () => ({
       auth_type: oidcRequested ? 'github-oidc/anthropic' : 'static-key',
diff --git a/containers/api-proxy/proxy-utils.oidc.test.js b/containers/api-proxy/proxy-utils.oidc.test.js
index b1a366b6b..705d58e1a 100644
--- a/containers/api-proxy/proxy-utils.oidc.test.js
+++ b/containers/api-proxy/proxy-utils.oidc.test.js
@@ -4,6 +4,7 @@ const {
   validateAuthHeaderEnv,
   createOidcRuntimeAdapterMethods,
   resolveOidcAuthHeaders,
+  resolveAuthHeadersWithFallback,
 } = require('./oidc-adapter-utils');
 
 describe('isValidHeaderName', () => {
@@ -106,3 +107,38 @@ describe('resolveOidcAuthHeaders', () => {
     expect(headers).toEqual({ Authorization: 'Bearer bearer-oidc-token' });
   });
 });
+
+describe('resolveAuthHeadersWithFallback', () => {
+  it('returns OIDC headers when token is available', () => {
+    const headers = resolveAuthHeadersWithFallback({
+      oidcProvider: { getToken: () => 'oidc-token' },
+      awsOidcProvider: null,
+      buildOidcHeaders: (token) => ({ Authorization: ['oidc', token].join(':') }),
+      staticHeaders: { 'x-api-key': 'static-token' },
+    });
+
+    expect(headers).toEqual({ Authorization: 'oidc:oidc-token' });
+  });
+
+  it('returns an empty object when OIDC is configured but token is unavailable', () => {
+    const headers = resolveAuthHeadersWithFallback({
+      oidcProvider: { getToken: () => '' },
+      awsOidcProvider: null,
+      buildOidcHeaders: () => ({ Authorization: 'ignored-token' }),
+      staticHeaders: { 'x-api-key': 'static-token' },
+    });
+
+    expect(headers).toEqual({});
+  });
+
+  it('falls back to static headers when OIDC is not configured', () => {
+    const headers = resolveAuthHeadersWithFallback({
+      oidcProvider: null,
+      awsOidcProvider: null,
+      buildOidcHeaders: () => ({ Authorization: 'ignored-token' }),
+      staticHeaders: { 'x-api-key': 'static-token' },
+    });
+
+    expect(headers).toEqual({ 'x-api-key': 'static-token' });
+  });
+});