@axiom-stack/mcp-server

Drop-in MCP server for the Axiom Stack Oracle — adds verifiable on-chain attestations (equity + crypto) to Claude Desktop, Cursor, Cline, and any other MCP-aware tool.

Run it via npx -y @axiom-stack/mcp-server from your client's config; the server forwards tool calls to api.axiomstack.dev/v1/* over Bearer auth. Thin proxy — no caching, no quota at the MCP layer (the API surface owns those concerns).

Install in Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "axiom": {
      "command": "npx",
      "args": ["-y", "@axiom-stack/mcp-server"],
      "env": {
        "AXIOM_API_KEY": "axm_live_…"
      }
    }
  }
}

Issue a key at axiomstack.dev/dashboard/keys. Restart Claude Desktop; the tools below appear in the tool picker.

Cursor and Cline use the same mcpServers schema — drop the same block into their config files.

Tools exposed

| Tool | Auth | Use | |---|---|---| | axiom_health | open | smoke-test reachability + see the deployed version / deployed_at | | axiom_list_assets | open | discover which classes + tiers are LIVE today | | axiom_attest_instant | Bearer | <2s data + provisional on-chain proof for equity (ticker) or crypto (BTC/ETH/SOL/USDC/USDT) | | axiom_attest_audit | Bearer | ~20s synchronous, fully on-chain attestation. V1 = equity only. Crypto + audit returns a typed tier-unavailable-for-class error with tiers_available you can pivot to. |

Tool inputs

• axiom_attest_instant / axiom_attest_audit:

  { "asset_class": 2,  "asset_id": "AAPL" }    // equity
  { "asset_class": 6,  "asset_id": "BTC"  }    // crypto (instant only in V1)

• axiom_health / axiom_list_assets: no input.

Result shape

Successful calls return { data: <typed-response>, request_id: "req_…" } as JSON text — the same {data, meta} envelope the REST API uses, with request_id included for support diagnostics.

Errors surface as MCP tool results with isError: true and the API's RFC 7807 body intact:

{
  "error": {
    "http_status": 400,
    "type": "https://docs.axiomstack.dev/errors/tier-unavailable-for-class",
    "title": "Tier unavailable for class",
    "detail": "The 'audit' tier is not available for asset_class 6 in V1.",
    "request_id": "req_…",
    "asset_class": 6,
    "tier_requested": "audit",
    "tiers_available": ["instant"],
    "note": "Crypto audit tier ships in G6.7b. Use latency_mode=instant for crypto in V1."
  }
}

Agent code can pattern-match on type URI for branching.

Configuration

| Env var | Effect | |---|---| | AXIOM_API_KEY (required for attestation tools) | Bearer token; issue at the dashboard. | | AXIOM_BASE_URL (optional) | Override the API base URL (e.g. for staging). Defaults to https://api.axiomstack.dev. |

Embedding (advanced)

import { buildServer, ApiClient } from "@axiom-stack/mcp-server";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";

const api = new ApiClient({ apiKey: "axm_live_…" });
const server = buildServer(api);
await server.connect(new StdioServerTransport());

Or call callTool(name, args, api) directly to test tool logic without booting a transport — see test/tools.test.ts.

Related packages

• axiom-stack (PyPI) — Python SDK for the same REST API. Sync + async clients, typed exceptions, minimal CLI.
• @axiom-stack/sdk (npm) — TypeScript SDK. Async/Promise client, typed exceptions, minimal CLI.

License

MIT © Axiom Stack LLC