feat: add GCP Vertex AI auth for Claude (alongside direct API key)

- New shared claude-client.ts: API key → GCP service account → GCP ADC
- QC engine, NLI engine, rationale validator all use shared client
- @anthropic-ai/vertex-sdk + google-auth-library added
- Fixed ttal.ts type error (clean build, zero TS errors)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.env.example

@@ -19,8 +19,13 @@ NEXT_PUBLIC_SKIP_AUTH=false
 # API Key for Gradio / external client authentication
 API_KEY=change-me-to-a-secret-key
 
-# Anthropic API (NLI Engine)
+# Claude API — set ONE of these auth methods:
+# Option 1: Direct Anthropic API key
 ANTHROPIC_API_KEY=your-anthropic-api-key
+# Option 2: GCP Vertex AI (base64-encoded service account JSON)
+# GCP_CREDENTIALS_JSON_B64=base64-encoded-json
+# GCP_PROJECT_ID=your-project-id
+# GCP_LOCATION=us-east5
 
 # Redis (QC Queue)
 REDIS_URL=redis://localhost:6379

package-lock.json

@@ -10,6 +10,7 @@
       "license": "MIT",
       "dependencies": {
         "@anthropic-ai/sdk": "^0.81.0",
+        "@anthropic-ai/vertex-sdk": "^0.14.4",
         "@aws-sdk/client-s3": "^3.1021.0",
         "@aws-sdk/s3-request-presigner": "^3.1021.0",
         "@hookform/resolvers": "^3.10.0",
@@ -56,6 +57,7 @@
         "express": "^4.21.2",
         "express-session": "^1.18.1",
         "framer-motion": "^11.13.1",
+        "google-auth-library": "^10.6.2",
         "input-otp": "^1.4.2",
         "ioredis": "^5.10.1",
         "lucide-react": "^0.453.0",
@@ -143,6 +145,105 @@
         }
       }
     },
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+      "license": "MIT",
+      "dependencies": {
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+        "https://github.com/sponsors/ctavan"
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@@ -6584,6 +6685,15 @@
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@@ -6941,6 +7051,15 @@
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@@ -7117,6 +7236,12 @@
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@@ -7622,6 +7747,15 @@
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@@ -7937,6 +8071,15 @@
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@@ -8335,6 +8484,29 @@
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@@ -8490,6 +8674,34 @@
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@@ -8592,6 +8804,32 @@
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+      "integrity": "sha512-SiPv/8VpZuWbvLSMtTDU8hEfrZWg/mH/nV/b4o0CYbSxu1UIQPLdwKOCIyLQX+VIPO5vrLX3i8qtqFyhdPSUSQ==",
+      "license": "MIT",
+      "dependencies": {
+        "bignumber.js": "^9.0.0"
+      }
+    },
     "node_modules/json-schema-to-ts": {
       "version": "3.1.1",
       "resolved": "https://registry.npmjs.org/json-schema-to-ts/-/json-schema-to-ts-3.1.1.tgz",
@@ -8930,6 +9264,27 @@
         "safe-buffer": "~5.1.0"
       }
     },
+    "node_modules/jwa": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/jwa/-/jwa-2.0.1.tgz",
+      "integrity": "sha512-hRF04fqJIP8Abbkq5NKGN0Bbr3JxlQ+qhZufXVr0DvujKy93ZCbXZMHDL4EOtodSbCWxOqR8MS1tXA5hwqCXDg==",
+      "license": "MIT",
+      "dependencies": {
+        "buffer-equal-constant-time": "^1.0.1",
+        "ecdsa-sig-formatter": "1.0.11",
+        "safe-buffer": "^5.0.1"
+      }
+    },
+    "node_modules/jws": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/jws/-/jws-4.0.1.tgz",
+      "integrity": "sha512-EKI/M/yqPncGUUh44xz0PxSidXFr/+r0pA70+gIYhjv+et7yxM+s29Y+VGDkovRofQem0fs7Uvf4+YmAdyRduA==",
+      "license": "MIT",
+      "dependencies": {
+        "jwa": "^2.0.1",
+        "safe-buffer": "^5.0.1"
+      }
+    },
     "node_modules/kysely": {
       "version": "0.28.10",
       "resolved": "https://registry.npmjs.org/kysely/-/kysely-0.28.10.tgz",
@@ -9784,6 +10139,44 @@
       "integrity": "sha512-AGK2yQKIjRuqnc6VkX2Xj5d+QW8xZ87pa1UK6yA6ouUyuxfHuMP6umE5QK7UmTeOAymo+Zx1Fxiuw9rVx8taHQ==",
       "license": "MIT"
     },
+    "node_modules/node-domexception": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/node-domexception/-/node-domexception-1.0.0.tgz",
+      "integrity": "sha512-/jKZoMpw0F8GRwl4/eLROPA3cfcXtLApP0QzLmUT/HuPCZWyB7IY9ZrMeKw2O/nFIqPQB3PVM9aYm0F312AXDQ==",
+      "deprecated": "Use your platform's native DOMException instead",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/jimmywarting"
+        },
+        {
+          "type": "github",
+          "url": "https://paypal.me/jimmywarting"
+        }
+      ],
+      "license": "MIT",
+      "engines": {
+        "node": ">=10.5.0"
+      }
+    },
+    "node_modules/node-fetch": {
+      "version": "3.3.2",
+      "resolved": "https://registry.npmjs.org/node-fetch/-/node-fetch-3.3.2.tgz",
+      "integrity": "sha512-dRB78srN/l6gqWulah9SrxeYnxeddIG30+GOqK/9OlLVyLg3HPnr6SqOWTWOXKRwC2eGYCkZ59NNuSgvSrpgOA==",
+      "license": "MIT",
+      "dependencies": {
+        "data-uri-to-buffer": "^4.0.0",
+        "fetch-blob": "^3.1.4",
+        "formdata-polyfill": "^4.0.10"
+      },
+      "engines": {
+        "node": "^12.20.0 || ^14.13.1 || >=16.0.0"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/node-fetch"
+      }
+    },
     "node_modules/node-gyp-build": {
       "version": "4.8.4",
       "resolved": "https://registry.npmjs.org/node-gyp-build/-/node-gyp-build-4.8.4.tgz",
@@ -11459,6 +11852,12 @@
         "node": ">=0.6"
       }
     },
+    "node_modules/tr46": {
+      "version": "0.0.3",
+      "resolved": "https://registry.npmjs.org/tr46/-/tr46-0.0.3.tgz",
+      "integrity": "sha512-N3WMsuqV66lT30CrXNbEjx4GEwlow3v6rr4mCcv6prnfwhS01rkgyFdjPNBYd9br7LpXV1+Emh01fHnq2Gdgrw==",
+      "license": "MIT"
+    },
     "node_modules/traverse": {
       "version": "0.3.9",
       "resolved": "https://registry.npmjs.org/traverse/-/traverse-0.3.9.tgz",
@@ -12853,6 +13252,31 @@
       "integrity": "sha512-MSZcA13R9ZlxgYpzfakaSYf8dz5tCdZKYbjtN1qnKbCi+UoyfaTuhvjlXHrITi/fgeO3qWfsH7U3BP1AKnwRNg==",
       "license": "BSD-3-Clause"
     },
+    "node_modules/web-streams-polyfill": {
+      "version": "3.3.3",
+      "resolved": "https://registry.npmjs.org/web-streams-polyfill/-/web-streams-polyfill-3.3.3.tgz",
+      "integrity": "sha512-d2JWLCivmZYTSIoge9MsgFCZrt571BikcWGYkjC1khllbTeDlGqZ2D8vD8E/lJa8WGWbb7Plm8/XJYV7IJHZZw==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 8"
+      }
+    },
+    "node_modules/webidl-conversions": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-3.0.1.tgz",
+      "integrity": "sha512-2JAn3z8AR6rjK8Sm8orRC0h/bcl/DqL7tRPdGZ4I1CjdF+EaMLmYxBHyXuKL849eucPFhvBoxMsflfOb8kxaeQ==",
+      "license": "BSD-2-Clause"
+    },
+    "node_modules/whatwg-url": {
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/whatwg-url/-/whatwg-url-5.0.0.tgz",
+      "integrity": "sha512-saE57nupxk6v3HY35+jzBwYa0rKSy0XR8JSxZPwgLr7ys0IBzhGviA1/TUGJLmSVqs8pb9AnvICXEuOHLprYTw==",
+      "license": "MIT",
+      "dependencies": {
+        "tr46": "~0.0.3",
+        "webidl-conversions": "^3.0.0"
+      }
+    },
     "node_modules/wouter": {
       "version": "3.9.0",
       "resolved": "https://registry.npmjs.org/wouter/-/wouter-3.9.0.tgz",

package.json

@@ -15,6 +15,7 @@
   },
   "dependencies": {
     "@anthropic-ai/sdk": "^0.81.0",
+    "@anthropic-ai/vertex-sdk": "^0.14.4",
     "@aws-sdk/client-s3": "^3.1021.0",
     "@aws-sdk/s3-request-presigner": "^3.1021.0",
     "@hookform/resolvers": "^3.10.0",
@@ -61,6 +62,7 @@
     "express": "^4.21.2",
     "express-session": "^1.18.1",
     "framer-motion": "^11.13.1",
+    "google-auth-library": "^10.6.2",
     "input-otp": "^1.4.2",
     "ioredis": "^5.10.1",
     "lucide-react": "^0.453.0",

src/lib/ai/claude-client.ts

@@ -0,0 +1,63 @@
+/**
+ * Claude Client Factory — supports both Anthropic API and GCP Vertex AI.
+ *
+ * Auth priority (mirrors Python claude_engine.py):
+ * 1. ANTHROPIC_API_KEY → direct Anthropic API
+ * 2. GCP_CREDENTIALS_JSON_B64 → Vertex AI with service account
+ * 3. GCP ADC (Application Default Credentials) → Vertex AI
+ */
+
+import Anthropic from "@anthropic-ai/sdk";
+import AnthropicVertex from "@anthropic-ai/vertex-sdk";
+
+let cachedClient: Anthropic | AnthropicVertex | null = null;
+let cachedAuthMethod: string = "";
+
+export function getClaudeClient(): { client: Anthropic | AnthropicVertex; authMethod: string } {
+  if (cachedClient) return { client: cachedClient, authMethod: cachedAuthMethod };
+
+  // 1. Direct Anthropic API key
+  const apiKey = process.env.ANTHROPIC_API_KEY;
+  if (apiKey) {
+    console.log("[Claude] Auth: using ANTHROPIC_API_KEY (direct API)");
+    cachedClient = new Anthropic({ apiKey });
+    cachedAuthMethod = "anthropic_api_key";
+    return { client: cachedClient, authMethod: cachedAuthMethod };
+  }
+
+  // 2. GCP service account (base64-encoded JSON)
+  const credsB64 = process.env.GCP_CREDENTIALS_JSON_B64;
+  const project = process.env.GCP_PROJECT_ID || process.env.GOOGLE_CLOUD_PROJECT || "";
+  const region = process.env.GCP_LOCATION || process.env.GOOGLE_CLOUD_LOCATION || "us-east5";
+
+  if (credsB64) {
+    const credsJson = JSON.parse(Buffer.from(credsB64, "base64").toString("utf-8"));
+    const projectId = project || credsJson.project_id || "";
+
+    // AnthropicVertex uses Google ADC or explicit credentials
+    // Set GOOGLE_APPLICATION_CREDENTIALS via the decoded JSON
+    const fs = require("fs");
+    const tmpPath = "/tmp/gcp-creds.json";
+    fs.writeFileSync(tmpPath, JSON.stringify(credsJson));
+    process.env.GOOGLE_APPLICATION_CREDENTIALS = tmpPath;
+
+    console.log(`[Claude] Auth: using GCP service account (Vertex AI, project=${projectId}, region=${region})`);
+    cachedClient = new AnthropicVertex({ projectId, region });
+    cachedAuthMethod = "gcp_service_account";
+    return { client: cachedClient, authMethod: cachedAuthMethod };
+  }
+
+  // 3. GCP ADC (Application Default Credentials)
+  if (project) {
+    console.log(`[Claude] Auth: using GCP ADC (Vertex AI, project=${project}, region=${region})`);
+    cachedClient = new AnthropicVertex({ projectId: project, region });
+    cachedAuthMethod = "gcp_adc";
+    return { client: cachedClient, authMethod: cachedAuthMethod };
+  }
+
+  // Fallback — try direct API without key (will fail at call time with clear error)
+  console.warn("[Claude] No auth configured. Set ANTHROPIC_API_KEY or GCP_CREDENTIALS_JSON_B64.");
+  cachedClient = new Anthropic();
+  cachedAuthMethod = "none";
+  return { client: cachedClient, authMethod: cachedAuthMethod };
+}

src/lib/editor/nli/engine.ts

@@ -3,7 +3,7 @@
  * receives structured tool calls back.
  */
 
-import Anthropic from "@anthropic-ai/sdk";
+import { getClaudeClient } from "../../ai/claude-client";
 import { NLI_TOOLS } from "./tools";
 import type { SubtitleData } from "../event-bus";
 
@@ -51,7 +51,7 @@ function formatSubtitlesForContext(subtitles: SubtitleData[]): string {
 export async function planNliExecution(
   request: NliRequest,
 ): Promise<NliResult> {
-  const client = new Anthropic();
+  const { client } = getClaudeClient();
 
   const contextParts: string[] = [
     `FPS: ${request.fps}`,

src/lib/editor/rationale-validator.ts

@@ -3,7 +3,7 @@
  * Catches: empty strings, random characters, "none", "n/a", "asdf", non-English, lazy input.
  */
 
-import Anthropic from "@anthropic-ai/sdk";
+import { getClaudeClient } from "../ai/claude-client";
 
 export interface RationaleEntry {
   index: number;
@@ -80,7 +80,7 @@ export async function validateRationales(
 
   // AI check with Haiku for the rest
   try {
-    const client = new Anthropic();
+    const { client } = getClaudeClient();
     const prompt = needsAiCheck
       .map((e) => `Index ${e.index}: "${e.rationale}"`)
       .join("\n");
@@ -93,8 +93,8 @@ export async function validateRationales(
     });
 
     const text = response.content
-      .filter((b): b is Anthropic.TextBlock => b.type === "text")
-      .map((b) => b.text)
+      .filter((b: any) => b.type === "text")
+      .map((b: any) => b.text)
       .join("");
 
     const jsonMatch = text.match(/\{[\s\S]*\}/);

src/lib/qc/engine.ts

@@ -3,7 +3,8 @@
  * IDENTICAL port from Python qc-report-generator/src/qc/checker.py + src/engines/claude_engine.py
  */
 
-import Anthropic from "@anthropic-ai/sdk";
+import type Anthropic from "@anthropic-ai/sdk";
+import { getClaudeClient } from "../ai/claude-client";
 import type { QCIssue, QCLine, QCModule, QCSeverity, QCSummary, QCResult } from "./types";
 import { runRuleChecks } from "./rule-checks";
 import { runNetflixChecks } from "./netflix-checks";
@@ -69,7 +70,7 @@ function backoffSeconds(attempt: number, isRateLimit: boolean): number {
 }
 
 async function callWithRetry(
-  client: Anthropic,
+  client: any, // Anthropic | AnthropicVertex — both have .messages.create()
   system: string,
   user: string,
   label: string,
@@ -85,8 +86,8 @@ async function callWithRetry(
         messages: [{ role: "user", content: user }],
       });
       const text = response.content
-        .filter((b): b is Anthropic.TextBlock => b.type === "text")
-        .map((b) => b.text)
+        .filter((b: any) => b.type === "text")
+        .map((b: any) => b.text)
         .join("");
       const dur = ((Date.now() - t0) / 1000).toFixed(1);
       log(`${label} — ${dur}s, prompt ${user.length} chars → response ${text.length} chars`);
@@ -194,7 +195,7 @@ export async function runQCPipeline(
   }
 
   log(`Pipeline start: ${filename}, ${lines.length} lines, module=${module}, lang=${language}, type=${deliverableType}`);
-  const client = new Anthropic();
+  const { client } = getClaudeClient();
   const { rules, systemExtra } = getModuleConfig(module);
 
   // ─── Stage 1: AI Batch QC ───