refactor(app): DRY pass — split large files, extract shared utils

S1: delete page.new.js (1724L abandoned) + remove dead getAntigravityProjectId
S2: split large files by natural seams
  - usage.js → usage/{github,google,claude,codex,kiro,minimax,misc,shared}.js
  - media-providers page → components/{Embedding,Tts,Generic,Stt}ExampleCard.js
  - EndpointPageClient → endpointConstants.js + endpointPing.js + components/
  - tokenRefresh.js → tokenRefresh/{dedup,providers}.js
  - ProviderLimits/index.js: 16 pure fn + 9 constants → utils.js
  - oauth/providers.js: 7 pure helpers → providerHelpers.js
S3: shared utils
  - getModelKind(m, fallback) → shared/constants/models.js (replaces 20× m.kind||m.type)
  - getStatusVariant → shared/utils/connectionStatus.js (dedup ConnectionRow/ConnectionsCard)
  - sseChunk → open-sse/utils/sse.js (dedup grok-web/perplexity-web)
  - fetchWithTimeout → usage/shared.js (replace 4× AbortController pattern in google.js)
fix: enableObservability2 field name in requestDetailsRepo
Co-authored-by: Cursor <cursoragent@cursor.com>

open-sse/services/tokenRefresh.js

@@ -1,73 +1,35 @@
-import { PROVIDERS, PROVIDER_OAUTH } from "../config/providers.js";
-import { OAUTH_ENDPOINTS, GITHUB_COPILOT, REFRESH_LEAD_MS } from "../config/appConstants.js";
-import { proxyAwareFetch } from "../utils/proxyFetch.js";
+import { PROVIDERS } from "../config/providers.js";
+import { OAUTH_ENDPOINTS, REFRESH_LEAD_MS } from "../config/appConstants.js";
+import {
+  refreshXaiToken,
+  refreshAccessToken,
+  refreshClaudeOAuthToken,
+  refreshGoogleToken,
+  refreshQwenToken,
+  refreshCodexToken,
+  refreshKiroToken,
+  refreshIflowToken,
+  refreshGitHubToken,
+  refreshCopilotToken,
+  classifyOAuthRefreshError,
+} from "./tokenRefresh/providers.js";
 
-// xAI refresh — wraps the class method from src/lib/oauth/services/xai.js so
-// the token-refresh switches below can stay flat (one function per provider).
-let _xaiServiceSingleton = null;
-async function refreshXaiToken(refreshToken, log) {
-  if (!refreshToken) return null;
-  return dedupRefresh("xai", refreshToken, async () => {
-    try {
-      if (!_xaiServiceSingleton) {
-        const mod = await import("../../src/lib/oauth/services/xai.js");
-        _xaiServiceSingleton = new mod.XaiService();
-      }
-      const tokens = await _xaiServiceSingleton.refreshAccessToken(refreshToken);
-      return {
-        accessToken: tokens.access_token,
-        refreshToken: tokens.refresh_token || refreshToken,
-        expiresIn: tokens.expires_in,
-        idToken: tokens.id_token,
-      };
-    } catch (e) {
-      log?.warn?.("TOKEN_REFRESH", `xai refresh failed: ${e?.message || e}`);
-      const msg = String(e?.message || "");
-      if (msg.includes("invalid_grant") || msg.includes("invalid_request")) {
-        return { error: "invalid_grant" };
-      }
-      return null;
-    }
-  }, log);
-}
+// Re-export all provider refresh functions (preserves public API for all consumers)
+export {
+  refreshAccessToken,
+  refreshClaudeOAuthToken,
+  refreshGoogleToken,
+  refreshQwenToken,
+  refreshCodexToken,
+  refreshKiroToken,
+  refreshIflowToken,
+  refreshGitHubToken,
+  refreshCopilotToken,
+  classifyOAuthRefreshError,
+};
 
-// Default token expiry buffer (refresh if expires within 5 minutes)
 export const TOKEN_EXPIRY_BUFFER_MS = 5 * 60 * 1000;
 
-// Dedup: cache in-flight promise + recent result to prevent refresh_token_reused (Auth0 family revoke)
-const REFRESH_RESULT_TTL_MS = 10_000;
-const refreshDedupCache = new Map();
-
-async function dedupRefresh(provider, oldToken, fn, log) {
-  if (!oldToken) return fn();
-  const key = `${provider}:${oldToken}`;
-  const hit = refreshDedupCache.get(key);
-  if (hit) {
-    if (hit.promise) {
-      log?.info?.("TOKEN_REFRESH", `Reusing in-flight refresh for ${provider}`);
-      return hit.promise;
-    }
-    if (hit.expiresAt > Date.now()) {
-      log?.info?.("TOKEN_REFRESH", `Reusing recent refresh result for ${provider}`);
-      return hit.result;
-    }
-    refreshDedupCache.delete(key);
-  }
-  const promise = (async () => {
-    try {
-      const result = await fn();
-      refreshDedupCache.set(key, { result, expiresAt: Date.now() + REFRESH_RESULT_TTL_MS });
-      return result;
-    } catch (err) {
-      refreshDedupCache.delete(key);
-      throw err;
-    }
-  })();
-  refreshDedupCache.set(key, { promise });
-  return promise;
-}
-
-// Check if refresh result indicates unrecoverable error (caller should stop retry, force re-auth)
 export function isUnrecoverableRefreshError(result) {
   return (
     result &&
@@ -79,543 +41,82 @@ export function isUnrecoverableRefreshError(result) {
   );
 }
 
-// Get provider-specific refresh lead time, falls back to default buffer
 export function getRefreshLeadMs(provider) {
   return REFRESH_LEAD_MS[provider] || TOKEN_EXPIRY_BUFFER_MS;
 }
 
-/**
- * Refresh OAuth access token using refresh token
- */
-export async function refreshAccessToken(provider, refreshToken, credentials, log) {
-  const config = PROVIDERS[provider];
-
-  if (!config || !config.refreshUrl) {
-    log?.warn?.("TOKEN_REFRESH", `No refresh URL configured for provider: ${provider}`);
-    return null;
-  }
-
-  if (!refreshToken) {
-    log?.warn?.("TOKEN_REFRESH", `No refresh token available for provider: ${provider}`);
-    return null;
-  }
-
-  return dedupRefresh(provider, refreshToken, async () => {
+export function parseVertexSaJson(apiKey) {
+  if (typeof apiKey !== "string") return null;
   try {
-    const response = await fetch(config.refreshUrl, {
-      method: "POST",
-      headers: {
-        "Content-Type": "application/x-www-form-urlencoded",
-        Accept: "application/json",
-      },
-      body: new URLSearchParams({
-        grant_type: "refresh_token",
-        refresh_token: refreshToken,
-        client_id: config.clientId,
-        client_secret: config.clientSecret,
-      }),
-    });
-
-    if (!response.ok) {
-      const errorText = await response.text();
-      log?.error?.("TOKEN_REFRESH", `Failed to refresh token for ${provider}`, {
-        status: response.status,
-        error: errorText,
-      });
-      return null;
+    const parsed = JSON.parse(apiKey);
+    if (parsed.type === "service_account" && parsed.client_email && parsed.private_key && parsed.project_id) {
+      return parsed;
     }
-
-    const tokens = await response.json();
-
-    log?.info?.("TOKEN_REFRESH", `Successfully refreshed token for ${provider}`, {
-      hasNewAccessToken: !!tokens.access_token,
-      hasNewRefreshToken: !!tokens.refresh_token,
-      expiresIn: tokens.expires_in,
-    });
-
-    return {
-      accessToken: tokens.access_token,
-      refreshToken: tokens.refresh_token || refreshToken,
-      expiresIn: tokens.expires_in,
-    };
-  } catch (error) {
-    log?.error?.("TOKEN_REFRESH", `Error refreshing token for ${provider}`, {
-      error: error.message,
-    });
     return null;
-  }
-  }, log);
-}
-
-/**
- * Specialized refresh for Claude OAuth tokens
- */
-export async function refreshClaudeOAuthToken(refreshToken, log) {
-  if (!refreshToken) return null;
-  return dedupRefresh("claude", refreshToken, async () => {
-  try {
-    const response = await fetch(OAUTH_ENDPOINTS.anthropic.token, {
-      method: "POST",
-      headers: {
-        "Content-Type": "application/json",
-        Accept: "application/json",
-      },
-      body: JSON.stringify({
-        grant_type: "refresh_token",
-        refresh_token: refreshToken,
-        client_id: PROVIDERS.claude.clientId,
-      }),
-    });
-
-    if (!response.ok) {
-      const errorText = await response.text();
-      log?.error?.("TOKEN_REFRESH", "Failed to refresh Claude OAuth token", { status: response.status, error: errorText });
-      return null;
-    }
-
-    const tokens = await response.json();
-    log?.info?.("TOKEN_REFRESH", "Successfully refreshed Claude OAuth token", { hasNewAccessToken: !!tokens.access_token, expiresIn: tokens.expires_in });
-    return { accessToken: tokens.access_token, refreshToken: tokens.refresh_token || refreshToken, expiresIn: tokens.expires_in };
-  } catch (error) {
-    log?.error?.("TOKEN_REFRESH", `Network error refreshing Claude token: ${error.message}`);
-    return null;
-  }
-  }, log);
-}
-
-/**
- * Specialized refresh for Google providers (Gemini, Antigravity)
- */
-export async function refreshGoogleToken(refreshToken, clientId, clientSecret, log) {
-  if (!refreshToken) return null;
-  return dedupRefresh(`google:${clientId}`, refreshToken, async () => {
-  try {
-    const response = await fetch(OAUTH_ENDPOINTS.google.token, {
-      method: "POST",
-      headers: {
-        "Content-Type": "application/x-www-form-urlencoded",
-        Accept: "application/json",
-      },
-      body: new URLSearchParams({
-        grant_type: "refresh_token",
-        refresh_token: refreshToken,
-        client_id: clientId,
-        client_secret: clientSecret,
-      }),
-    });
-
-    if (!response.ok) {
-      const errorText = await response.text();
-      log?.error?.("TOKEN_REFRESH", "Failed to refresh Google token", { status: response.status, error: errorText });
-      return null;
-    }
-
-    const tokens = await response.json();
-    log?.info?.("TOKEN_REFRESH", "Successfully refreshed Google token", { hasNewAccessToken: !!tokens.access_token, expiresIn: tokens.expires_in });
-    return { accessToken: tokens.access_token, refreshToken: tokens.refresh_token || refreshToken, expiresIn: tokens.expires_in };
-  } catch (error) {
-    log?.error?.("TOKEN_REFRESH", `Network error refreshing Google token: ${error.message}`);
-    return null;
-  }
-  }, log);
-}
-
-/**
- * Specialized refresh for Qwen OAuth tokens
- */
-export async function refreshQwenToken(refreshToken, log) {
-  if (!refreshToken) return null;
-  return dedupRefresh("qwen", refreshToken, async () => {
-  const endpoint = OAUTH_ENDPOINTS.qwen.token;
-
-  try {
-    const response = await fetch(endpoint, {
-      method: "POST",
-      headers: {
-        "Content-Type": "application/x-www-form-urlencoded",
-        Accept: "application/json",
-      },
-      body: new URLSearchParams({
-        grant_type: "refresh_token",
-        refresh_token: refreshToken,
-        client_id: PROVIDERS.qwen.clientId,
-      }),
-    });
-
-    if (response.status === 200) {
-      const tokens = await response.json();
-
-      log?.info?.("TOKEN_REFRESH", "Successfully refreshed Qwen token", {
-        hasNewAccessToken: !!tokens.access_token,
-        hasNewRefreshToken: !!tokens.refresh_token,
-        expiresIn: tokens.expires_in,
-      });
-
-      return {
-        accessToken: tokens.access_token,
-        refreshToken: tokens.refresh_token || refreshToken,
-        expiresIn: tokens.expires_in,
-        providerSpecificData: tokens.resource_url
-          ? { resourceUrl: tokens.resource_url }
-          : undefined,
-      };
-    } else {
-      const errorText = await response.text().catch(() => "");
-      log?.warn?.("TOKEN_REFRESH", `Error with Qwen endpoint`, {
-        status: response.status,
-        error: errorText,
-      });
-    }
-  } catch (error) {
-    log?.warn?.("TOKEN_REFRESH", `Network error trying Qwen endpoint`, {
-      error: error.message,
-    });
-  }
-
-  log?.error?.("TOKEN_REFRESH", "Failed to refresh Qwen token");
-  return null;
-  }, log);
-}
-
-export function classifyOAuthRefreshError(errorText = "", status = 0) {
-  let parsed = null;
-  try {
-    parsed = errorText ? JSON.parse(errorText) : null;
   } catch {
-    parsed = null;
-  }
-
-  const code = parsed?.error?.code || parsed?.error || parsed?.error_code || "";
-  const description = parsed?.error_description || parsed?.message || errorText || "";
-  const combined = `${code} ${description}`.toLowerCase();
-  const permanent = [
-    "refresh_token_expired",
-    "refresh_token_reused",
-    "refresh_token_invalidated",
-    "invalid_grant",
-  ].some((marker) => combined.includes(marker));
-
-  return { status, code, description, permanent };
-}
-
-/**
- * Specialized refresh for Codex (OpenAI) OAuth tokens.
- * OpenAI uses rotating (one-time-use) refresh tokens.
- * Returns { error: 'unrecoverable_refresh_error' } when token already consumed/invalid,
- * so callers stop retrying and request re-authentication.
- */
-export async function refreshCodexToken(refreshToken, log) {
-  if (!refreshToken) return null;
-  return dedupRefresh("codex", refreshToken, async () => {
-    try {
-      const response = await fetch(OAUTH_ENDPOINTS.openai.token, {
-        method: "POST",
-        headers: {
-          "Content-Type": "application/json",
-          Accept: "application/json",
-        },
-        body: JSON.stringify({
-          client_id: PROVIDERS.codex.clientId,
-          grant_type: "refresh_token",
-          refresh_token: refreshToken,
-        }),
-      });
-
-      if (!response.ok) {
-        const errorText = await response.text();
-        const failure = classifyOAuthRefreshError(errorText, response.status);
-        if (failure.permanent) {
-          log?.error?.("TOKEN_REFRESH", "Codex refresh token already used or invalid. Re-auth required.", {
-            status: response.status,
-            code: failure.code,
-          });
-          return { error: "unrecoverable_refresh_error", code: failure.code };
-        }
-
-        log?.error?.("TOKEN_REFRESH", "Failed to refresh Codex token", {
-          status: response.status,
-          error: errorText,
-          code: failure.code,
-          permanent: failure.permanent,
-        });
-        return null;
-      }
-
-      const tokens = await response.json();
-
-      log?.info?.("TOKEN_REFRESH", "Successfully refreshed Codex token", {
-        hasNewAccessToken: !!tokens.access_token,
-        hasNewRefreshToken: !!tokens.refresh_token,
-        hasIdToken: !!tokens.id_token,
-        expiresIn: tokens.expires_in,
-      });
-
-      return {
-        accessToken: tokens.access_token,
-        refreshToken: tokens.refresh_token || refreshToken,
-        idToken: tokens.id_token,
-        expiresIn: tokens.expires_in,
-      };
-    } catch (error) {
-      log?.error?.("TOKEN_REFRESH", `Network error refreshing Codex token: ${error.message}`);
-      return null;
-    }
-  }, log);
-}
-
-/**
- * Specialized refresh for Kiro (AWS CodeWhisperer) tokens
- * Supports both AWS SSO OIDC (Builder ID/IDC) and Social Auth (Google/GitHub)
- */
-// Backfill missing Kiro profileArn on refresh so existing IDC connections self-heal
-async function resolveKiroProfileArnPatch(providerSpecificData, accessToken, refreshedArn) {
-  if (providerSpecificData?.profileArn) return {};
-  let profileArn = refreshedArn?.trim?.() || null;
-  if (!profileArn) {
-    const { fetchKiroProfileArn } = await import("../../src/lib/oauth/providers.js");
-    profileArn = await fetchKiroProfileArn(accessToken);
-  }
-  return profileArn ? { providerSpecificData: { profileArn } } : {};
-}
-
-export async function refreshKiroToken(refreshToken, providerSpecificData, log, proxyOptions = null) {
-  if (!refreshToken) return null;
-  return dedupRefresh("kiro", refreshToken, async () => {
-  const authMethod = providerSpecificData?.authMethod;
-  const clientId = providerSpecificData?.clientId;
-  const clientSecret = providerSpecificData?.clientSecret;
-  const region = providerSpecificData?.region;
-
-  // AWS SSO OIDC (Builder ID or IDC)
-  // If clientId and clientSecret exist, assume AWS SSO OIDC (default to builder-id if authMethod not specified)
-  if (clientId && clientSecret) {
-    const isIDC = authMethod === "idc";
-    const endpoint = isIDC && region
-      ? `https://oidc.${region}.amazonaws.com/token`
-      : "https://oidc.us-east-1.amazonaws.com/token";
-
-    const response = await proxyAwareFetch(endpoint, {
-      method: "POST",
-      headers: {
-        "Content-Type": "application/json",
-        Accept: "application/json",
-      },
-      body: JSON.stringify({
-        clientId: clientId,
-        clientSecret: clientSecret,
-        refreshToken: refreshToken,
-        grantType: "refresh_token",
-      }),
-    }, proxyOptions);
-
-    if (!response.ok) {
-      const errorText = await response.text();
-      log?.error?.("TOKEN_REFRESH", "Failed to refresh Kiro AWS token", {
-        status: response.status,
-        error: errorText,
-      });
-      return null;
-    }
-
-    const tokens = await response.json();
-
-    log?.info?.("TOKEN_REFRESH", "Successfully refreshed Kiro AWS token", {
-      hasNewAccessToken: !!tokens.accessToken,
-      expiresIn: tokens.expiresIn,
-    });
-
-    return {
-      accessToken: tokens.accessToken,
-      refreshToken: tokens.refreshToken || refreshToken,
-      expiresIn: tokens.expiresIn,
-      ...(await resolveKiroProfileArnPatch(providerSpecificData, tokens.accessToken, tokens.profileArn)),
-    };
-  }
-
-  // Social Auth (Google/GitHub) - use Kiro's refresh endpoint
-  const response = await proxyAwareFetch(PROVIDERS.kiro.tokenUrl, {
-    method: "POST",
-    headers: {
-      "Content-Type": "application/json",
-      Accept: "application/json",
-      "User-Agent": "kiro-cli/1.0.0",
-    },
-    body: JSON.stringify({
-      refreshToken: refreshToken,
-    }),
-  }, proxyOptions);
-
-  if (!response.ok) {
-    const errorText = await response.text();
-    log?.error?.("TOKEN_REFRESH", "Failed to refresh Kiro social token", {
-      status: response.status,
-      error: errorText,
-    });
     return null;
   }
-
-  const tokens = await response.json();
-
-  log?.info?.("TOKEN_REFRESH", "Successfully refreshed Kiro social token", {
-    hasNewAccessToken: !!tokens.accessToken,
-    expiresIn: tokens.expiresIn,
-  });
-
-  return {
-    accessToken: tokens.accessToken,
-    refreshToken: tokens.refreshToken || refreshToken,
-    expiresIn: tokens.expiresIn,
-    ...(await resolveKiroProfileArnPatch(providerSpecificData, tokens.accessToken, tokens.profileArn)),
-  };
-  }, log);
 }
 
-/**
- * Specialized refresh for iFlow OAuth tokens
- */
-export async function refreshIflowToken(refreshToken, log) {
-  if (!refreshToken) return null;
-  return dedupRefresh("iflow", refreshToken, async () => {
-  const basicAuth = btoa(`${PROVIDERS.iflow.clientId}:${PROVIDERS.iflow.clientSecret}`);
+// Cache Vertex tokens keyed by service account email { token, expiresAt }
+const vertexTokenCache = new Map();
 
-  const response = await fetch(OAUTH_ENDPOINTS.iflow.token, {
-    method: "POST",
-    headers: {
-      "Content-Type": "application/x-www-form-urlencoded",
-      Accept: "application/json",
-      Authorization: `Basic ${basicAuth}`,
-    },
-    body: new URLSearchParams({
-      grant_type: "refresh_token",
-      refresh_token: refreshToken,
-      client_id: PROVIDERS.iflow.clientId,
-      client_secret: PROVIDERS.iflow.clientSecret,
-    }),
-  });
+export async function refreshVertexToken(saJson, log) {
+  const cacheKey = saJson.client_email;
+  const cached = vertexTokenCache.get(cacheKey);
 
-  if (!response.ok) {
-    const errorText = await response.text();
-    log?.error?.("TOKEN_REFRESH", "Failed to refresh iFlow token", {
-      status: response.status,
-      error: errorText,
-    });
-    return null;
+  if (cached && cached.expiresAt - Date.now() > 5 * 60 * 1000) {
+    return { accessToken: cached.token, expiresAt: cached.expiresAt };
   }
 
-  const tokens = await response.json();
-
-  log?.info?.("TOKEN_REFRESH", "Successfully refreshed iFlow token", {
-    hasNewAccessToken: !!tokens.access_token,
-    hasNewRefreshToken: !!tokens.refresh_token,
-    expiresIn: tokens.expires_in,
-  });
-
-  return {
-    accessToken: tokens.access_token,
-    refreshToken: tokens.refresh_token || refreshToken,
-    expiresIn: tokens.expires_in,
-  };
-  }, log);
-}
-
-/**
- * Specialized refresh for GitHub Copilot OAuth tokens
- */
-export async function refreshGitHubToken(refreshToken, log) {
-  if (!refreshToken) return null;
-  return dedupRefresh("github", refreshToken, async () => {
-  const params = {
-    grant_type: "refresh_token",
-    refresh_token: refreshToken,
-    client_id: PROVIDERS.github.clientId,
-  };
-  if (PROVIDERS.github.clientSecret) {
-    params.client_secret = PROVIDERS.github.clientSecret;
-  }
-
-  const response = await fetch(OAUTH_ENDPOINTS.github.token, {
-    method: "POST",
-    headers: {
-      "Content-Type": "application/x-www-form-urlencoded",
-      Accept: "application/json",
-    },
-    body: new URLSearchParams(params),
-  });
-
-  if (!response.ok) {
-    const errorText = await response.text();
-    log?.error?.("TOKEN_REFRESH", "Failed to refresh GitHub token", {
-      status: response.status,
-      error: errorText,
-    });
-    return null;
-  }
-
-  const tokens = await response.json();
-
-  log?.info?.("TOKEN_REFRESH", "Successfully refreshed GitHub token", {
-    hasNewAccessToken: !!tokens.access_token,
-    hasNewRefreshToken: !!tokens.refresh_token,
-    expiresIn: tokens.expires_in,
-  });
-
-  return {
-    accessToken: tokens.access_token,
-    refreshToken: tokens.refresh_token || refreshToken,
-    expiresIn: tokens.expires_in,
-  };
-  }, log);
-}
-
-/**
- * Refresh GitHub Copilot token using GitHub access token
- */
-export async function refreshCopilotToken(githubAccessToken, log) {
-  if (!githubAccessToken) return null;
-  return dedupRefresh("copilot", githubAccessToken, async () => {
   try {
-    const response = await fetch(PROVIDER_OAUTH["github"]?.copilotTokenUrl, {
-      headers: {
-        "Authorization": `token ${githubAccessToken}`,
-        "User-Agent": GITHUB_COPILOT.USER_AGENT,
-        "Editor-Version": `vscode/${GITHUB_COPILOT.VSCODE_VERSION}`,
-        "Editor-Plugin-Version": `copilot-chat/${GITHUB_COPILOT.COPILOT_CHAT_VERSION}`,
-        "Accept": "application/json",
-        "x-github-api-version": GITHUB_COPILOT.API_VERSION
-      }
+    const { SignJWT, importPKCS8 } = await import("jose");
+    log?.debug?.("TOKEN_REFRESH", `Vertex minting token for ${saJson.client_email}`);
+    const privateKey = await importPKCS8(saJson.private_key.replace(/\\n/g, "\n"), "RS256");
+    const now = Math.floor(Date.now() / 1000);
+
+    const jwt = await new SignJWT({ scope: "https://www.googleapis.com/auth/cloud-platform" })
+      .setProtectedHeader({ alg: "RS256" })
+      .setIssuer(saJson.client_email)
+      .setAudience(OAUTH_ENDPOINTS.google.token)
+      .setIssuedAt(now)
+      .setExpirationTime(now + 3600)
+      .sign(privateKey);
+
+    const res = await fetch(OAUTH_ENDPOINTS.google.token, {
+      method: "POST",
+      headers: { "Content-Type": "application/x-www-form-urlencoded" },
+      body: new URLSearchParams({
+        grant_type: "urn:ietf:params:oauth:grant-type:jwt-bearer",
+        assertion: jwt,
+      }),
     });
 
-    if (!response.ok) {
-      const errorText = await response.text();
-      log?.error?.("TOKEN_REFRESH", "Failed to refresh Copilot token", {
-        status: response.status,
-        error: errorText
-      });
+    if (!res.ok) {
+      const err = await res.text();
+      log?.error?.("TOKEN_REFRESH", `Vertex token mint failed: ${err}`);
       return null;
     }
 
-    const data = await response.json();
+    const { access_token, expires_in } = await res.json();
+    const expiresAt = Date.now() + (expires_in ?? 3600) * 1000;
 
-    log?.info?.("TOKEN_REFRESH", "Successfully refreshed Copilot token", {
-      hasToken: !!data.token,
-      expiresAt: data.expires_at
-    });
+    vertexTokenCache.set(cacheKey, { token: access_token, expiresAt });
+    log?.info?.("TOKEN_REFRESH", `Vertex token minted for ${saJson.client_email}`);
 
-    return {
-      token: data.token,
-      expiresAt: data.expires_at
-    };
+    return { accessToken: access_token, expiresAt };
   } catch (error) {
-    log?.error?.("TOKEN_REFRESH", "Error refreshing Copilot token", {
-      error: error.message
-    });
+    log?.error?.("TOKEN_REFRESH", `Vertex token error: ${error.message}`);
     return null;
   }
-  }, log);
 }
 
-// Single source of per-provider refresh dispatch (logic stays in each refreshXxx fn).
-// Each handler: (credentials, log) => Promise<tokens|null>
+function vertexRefreshHandler(c, log) {
+  const saJson = parseVertexSaJson(c.apiKey);
+  if (!saJson) return null;
+  return refreshVertexToken(saJson, log);
+}
+
 const REFRESH_HANDLERS = {
   "gemini-cli": (c, log) => refreshGoogleToken(c.refreshToken, PROVIDERS["gemini-cli"].clientId, PROVIDERS["gemini-cli"].clientSecret, log),
   antigravity: (c, log) => refreshGoogleToken(c.refreshToken, PROVIDERS.antigravity.clientId, PROVIDERS.antigravity.clientSecret, log),
@@ -630,28 +131,15 @@ const REFRESH_HANDLERS = {
   "vertex-partner": vertexRefreshHandler
 };
 
-function vertexRefreshHandler(c, log) {
-  const saJson = parseVertexSaJson(c.apiKey);
-  if (!saJson) return null;
-  return refreshVertexToken(saJson, log);
-}
-
-/**
- * Get access token for a specific provider (with in-flight dedup).
- * If a refresh is already in-flight for same provider+token, share the promise
- * to prevent parallel OAuth requests → Auth0 'refresh_token_reused' family revoke.
- */
 export async function getAccessToken(provider, credentials, log) {
   if (!credentials || !credentials.refreshToken || typeof credentials.refreshToken !== "string") {
     log?.warn?.("TOKEN_REFRESH", `No valid refresh token available for provider: ${provider}`);
     return null;
   }
-  // Dedup is handled inside each refreshXxxToken function
   return _getAccessTokenInternal(provider, credentials, log);
 }
 
 async function _getAccessTokenInternal(provider, credentials, log) {
-  // "gemini" shares Google refresh here (unlike refreshTokenByProvider)
   if (provider === "gemini") {
     return refreshGoogleToken(credentials.refreshToken, PROVIDERS.gemini.clientId, PROVIDERS.gemini.clientSecret, log);
   }
@@ -663,19 +151,12 @@ async function _getAccessTokenInternal(provider, credentials, log) {
   return handler(credentials, log);
 }
 
-/**
- * Refresh token by provider type (helper for handlers)
- */
 export async function refreshTokenByProvider(provider, credentials, log) {
   if (!credentials.refreshToken) return null;
   const handler = REFRESH_HANDLERS[provider];
-  // default: generic refresh (note: "gemini" is NOT special-cased here, by design)
   return handler ? handler(credentials, log) : refreshAccessToken(provider, credentials.refreshToken, credentials, log);
 }
 
-/**
- * Format credentials for provider
- */
 export function formatProviderCredentials(provider, credentials, log) {
   const config = PROVIDERS[provider];
   if (!config) {
@@ -725,9 +206,6 @@ export function formatProviderCredentials(provider, credentials, log) {
   }
 }
 
-/**
- * Get all access tokens for a user
- */
 export async function getAllAccessTokens(userInfo, log) {
   const results = {};
 
@@ -748,89 +226,6 @@ export async function getAllAccessTokens(userInfo, log) {
   return results;
 }
 
-/**
- * Parse Vertex AI Service Account JSON from apiKey string
- */
-export function parseVertexSaJson(apiKey) {
-  if (typeof apiKey !== "string") return null;
-  try {
-    const parsed = JSON.parse(apiKey);
-    if (parsed.type === "service_account" && parsed.client_email && parsed.private_key && parsed.project_id) {
-      return parsed;
-    }
-    return null;
-  } catch {
-    return null;
-  }
-}
-
-// Cache Vertex tokens keyed by service account email { token, expiresAt }
-const vertexTokenCache = new Map();
-
-/**
- * Mint a short-lived OAuth2 Bearer token for Google Cloud Vertex AI
- * using Service Account JSON + jose (RS256 JWT assertion flow).
- * Token is cached until 5 minutes before expiry.
- */
-export async function refreshVertexToken(saJson, log) {
-  const cacheKey = saJson.client_email;
-  const cached = vertexTokenCache.get(cacheKey);
-
-  // Return cached token if still valid (5-min buffer)
-  if (cached && cached.expiresAt - Date.now() > 5 * 60 * 1000) {
-    return { accessToken: cached.token, expiresAt: cached.expiresAt };
-  }
-
-  try {
-    const { SignJWT, importPKCS8 } = await import("jose");
-    log?.debug?.("TOKEN_REFRESH", `Vertex minting token for ${saJson.client_email}`);
-    const privateKey = await importPKCS8(saJson.private_key.replace(/\\n/g, "\n"), "RS256");
-    const now = Math.floor(Date.now() / 1000);
-
-    const jwt = await new SignJWT({ scope: "https://www.googleapis.com/auth/cloud-platform" })
-      .setProtectedHeader({ alg: "RS256" })
-      .setIssuer(saJson.client_email)
-      .setAudience(OAUTH_ENDPOINTS.google.token)
-      .setIssuedAt(now)
-      .setExpirationTime(now + 3600)
-      .sign(privateKey);
-
-    const res = await fetch(OAUTH_ENDPOINTS.google.token, {
-      method: "POST",
-      headers: { "Content-Type": "application/x-www-form-urlencoded" },
-      body: new URLSearchParams({
-        grant_type: "urn:ietf:params:oauth:grant-type:jwt-bearer",
-        assertion: jwt,
-      }),
-    });
-
-    if (!res.ok) {
-      const err = await res.text();
-      log?.error?.("TOKEN_REFRESH", `Vertex token mint failed: ${err}`);
-      return null;
-    }
-
-    const { access_token, expires_in } = await res.json();
-    const expiresAt = Date.now() + (expires_in ?? 3600) * 1000;
-
-    vertexTokenCache.set(cacheKey, { token: access_token, expiresAt });
-    log?.info?.("TOKEN_REFRESH", `Vertex token minted for ${saJson.client_email}`);
-
-    return { accessToken: access_token, expiresAt };
-  } catch (error) {
-    log?.error?.("TOKEN_REFRESH", `Vertex token error: ${error.message}`);
-    return null;
-  }
-}
-
-/**
- * Refresh token with retry and exponential backoff
- * Retries on failure with increasing delay: 1s, 2s, 3s...
- * @param {function} refreshFn - Async function that returns token or null
- * @param {number} maxRetries - Max retry attempts (default 3)
- * @param {object} log - Logger instance (optional)
- * @returns {Promise<object|null>} Token result or null if all retries fail
- */
 export async function refreshWithRetry(refreshFn, maxRetries = 3, log = null) {
   for (let attempt = 0; attempt < maxRetries; attempt++) {
     if (attempt > 0) {