Chit402 MCP (xfuel-mcp / chit402-mcp)

MCP server for Chit402 — returns the book and verify_url, not another chat wrapper.

First hour: list_models → chat_completions (unmetered POST /v1/chat/completions). Book: register_agent → get_book / get_agent_book (possession-gated last-N spend). Prove it: verify_receipt (offline binding via @xfuel/verify). SP1 tools (get_proof, verify_proof) are optional Tier-2.

Zero config talks to https://api.chit402.com (alias: https://api.xfuel.app) with demo key chit402-demo.

Public beta. Paying that host moves real USDC on Base or Solana. MCP does not take a human private key — the payer stays client-side (Eliza plugin, wallet, etc.).

npm: xfuel-mcp · alias: chit402-mcp · Registry: io.github.XFuel-Lab/xfuel-mcp

Run

npx chit402-mcp
# or
npx xfuel-mcp

npx chit402-mcp --http --port 3033

CHIT402_API_KEY=your-key CHIT402_API_URL=https://your-host npx chit402-mcp
# aliases: CHIT_API_URL, CHIT_API_KEY, XFUEL_API_URL, XFUEL_API_KEY

Claude / Cursor stdio config:

{
  "mcpServers": {
    "chit402": {
      "command": "npx",
      "args": ["-y", "chit402-mcp"],
      "env": {
        "CHIT402_API_URL": "https://api.chit402.com",
        "CHIT402_API_KEY": "chit402-demo"
      }
    }
  }
}

Example tool result (chat_completions)

Every receipt-bearing tool returns structuredContent with a top-level verify_url (not stripped by nested xfuel only):

{
  "model": "xfuel/auto",
  "choices": [{ "message": { "role": "assistant", "content": "Hello." } }],
  "xfuel": {
    "task_id": "openai-abc123",
    "verify_url": "https://api.chit402.com/receipt/openai-abc123",
    "payment": { "rail": "unmetered" }
  },
  "task_id": "openai-abc123",
  "verify_url": "https://api.chit402.com/receipt/openai-abc123"
}

Human-readable content[0].text also includes Verify/share: … for clients that only render text.

Tools

| Tool | Purpose | |------|---------| | chat_completions | Generate text (unmetered /v1). Returns top-level verify_url. | | list_models | Live catalog — hub, modality, pricing, availability | | register_agent | POST /v1/agents/register — bind agentWallet + collected receipt → agent_id | | get_book / get_agent_book | Possession-gated last-N collected spend + budget Y / remaining | | verify_receipt | Offline receipt verify (@xfuel/verify) — default prove-it path | | submit_inference | Paid /task-request. 402 without a payer. Amount USDC 6dp. | | get_task_status | Status / fees for a task id | | get_proof / verify_proof | Optional Tier-2 SP1 settlement (not default) | | quote_task / get_health | Pricing / health | | verify_model_commitment | PoMA check (needs RPC + registry) | | get_verified_quote | Price + available trust tiers | | get_validation_status | ERC-8004 validation record | | get_provider_stake | Stake / slash history | | get_my_stats | Usage for the configured key (demo key is shared) |

API gaps (honest)

• Book requires a possession session from register_agent; demo/unmetered receipts do not qualify for registration.
• Budget Y is set via POST body on /v1/agents/:id/book; MCP exposes optional budget on get_book / get_agent_book.
• Book policy / assign / dispute / ingest / rotate / lineage endpoints exist on the gateway but are not MCP tools yet — call HTTP or extend the server if you need them.
• Payment for paid inference is not in MCP (by design). Use the Eliza plugin or x402 client-side payer.

Test / smoke

cd packages/mcp
npm install
npm test
npm run smoke

Publish (maintainers)

Publish xfuel-sdk and @xfuel/verify first, then:

cd packages/mcp
npm publish --access public --auth-type=web

See ../sdk/PUBLISHING.md.

Docs

• docs/M2M_API.md
• docs/CHAT_COMPLETIONS_GATEWAY.md
• Agent playbook