Tavily-Proxy

A Cloudflare Worker that acts as an MCP (Model Context Protocol) proxy for the Tavily API. It provides the same tools as the official Tavily MCP server, but with an API key pool — automatically rotating through multiple Tavily keys and selecting the one with the most remaining credit.

Features

• MCP Server — Streamable HTTP transport at POST /mcp, compatible with any MCP client

• 4 Tavily Tools — tavily-search, tavily-extract, tavily-crawl, tavily-map

• API Key Pool — Multiple Tavily API keys stored in Cloudflare KV; each request picks the least-recently-used healthy key

• Health-aware routing — Tavily 432 (quota exhausted) keys are skipped until the next UTC month; 429 rate limits apply a transient cooldown; 401/403 keys are invalidated

• Key Management API + Admin Panel — HTTP endpoints plus an embedded web panel (GET /admin) to add/delete keys and monitor usage

• Auth Protected — All endpoints except GET / and GET /admin require an x-api-key header

Related MCP server: MCP Nexus

Usage

Connect MCP Clients

With mcp-remote (for clients like Cursor, Claude Desktop, etc.):

{
  "mcpServers": {
    "tavily-proxy": {
      "command": "npx",
      "args": [
        "-y", "mcp-remote",
        "https://your-worker.workers.dev/mcp",
        "--header", "x-api-key:${AUTH_KEY}"
      ],
      "env": {
        "AUTH_KEY": "your-auth-key"
      }
    }
  }
}

Admin Panel

Open https://your-worker.workers.dev/admin in a browser. The panel asks for your AUTH_KEY (kept in the browser's sessionStorage), then lets you:

• List all keys — masked key, status (active / exhausted / cooling), credit availability, last-used and last-synced times

• Add and delete keys

• Force a usage sync via the Sync usage now button

Key Management

# Add a key (auto-queries remaining credit from Tavily)
curl -X POST https://your-worker.workers.dev/api/keys \
  -H "Content-Type: application/json" \
  -H "x-api-key: your-auth-key" \
  -d '{"apiKey": "tvly-xxx"}'

# List all keys and credits
curl https://your-worker.workers.dev/api/keys \
  -H "x-api-key: your-auth-key"

# Force a usage sync for all keys
curl -X POST https://your-worker.workers.dev/api/keys/sync \
  -H "x-api-key: your-auth-key"

# Delete a key
curl -X DELETE https://your-worker.workers.dev/api/keys \
  -H "Content-Type: application/json" \
  -H "x-api-key: your-auth-key" \
  -d '{"apiKey": "tvly-xxx"}'

Setup

Web

Click the button below to deploy your own instance of tavily-proxy directly to Cloudflare Workers:

1. Configure KV Namespace: The API key pool is stored in Cloudflare KV. You need create a namespace (Workers & Pages → KV → Create a namespace(name don't important).

2. Configure KV Binding: After creating the namespace, you need to bind it to your Worker. Go to your Cloudflare Worker dashboard → Settings → Bindings → Add binding and select the KV namespace you created.

3. Configure Secrets: Once deployed successfully, go to your Cloudflare Worker dashboard → Settings → Variables. Add AUTH_KEY as an encrypted secret — it is the x-api-key header that protects the admin panel and management API.

4. Redeploy: Trigger a redeploy for the secret to take effect.

5. Add Keys: Visit your Worker URL at /admin, log in with your AUTH_KEY, and add your Tavily API key(s). The pool is ready — requests are served through POST /mcp.

6. (Optional) If you need custom domain, go to your Cloudflare Worker dashboard → Settings → Custom domains → Add a custom domain.

How the Key Pool Works

The design follows tavily-hikari: the request hot path does not estimate or deduct credits locally. Key health is driven by real upstream signals:

1. Each request picks the least-recently-used healthy key (LRU).

2. HTTP 432 (Tavily quota exhausted) → the key is marked exhausted and skipped for the rest of the current UTC month; it is restored automatically at the next monthly reset.

3. HTTP 429 (rate limited) → the key is cooled down for the Retry-After window (fallback 60s) and the next key is tried.

4. HTTP 401/403 → the key is marked exhausted and retried against the next key.

5. Remaining credit is only a display field, synced from Tavily's /usage endpoint in the background:

   • POST /api/keys queries usage when adding a key.

   • GET /api/keys returns cached values and kicks off a background sync when they are stale (>30 min).

   • POST /api/keys/sync forces a full sync.

Workers Free Plan Note

Cron triggers do not fire on the Workers Free plan. The scheduled handler is still included, but on Free you should rely on the lazy sync built into GET /api/keys and the admin panel's Sync usage now button. Uncomment the [triggers] block in wrangler.toml to enable hourly cron syncs after upgrading to a paid plan.

Endpoints

All endpoints except GET / and GET /admin require the x-api-key header matching your configured AUTH_KEY.