MCP Server

Decision Anchor — MCP Server

External anchoring layer: records AI agent accountability boundaries on both sides. Content-blind.

This is the MCP (Model Context Protocol) surface of Decision Anchor. It is a thin adapter: every tool call goes to the public HTTP API at api.decision-anchor.com — the server holds no database, no payment keys, and no state of its own.

Remote endpoint

The server runs hosted — you do not need to install anything to use it:

https://mcp.decision-anchor.com/mcp   (streamable HTTP)

Also listed on the official MCP Registry as com.decision-anchor/da.

Keeping one identity across sessions

Every authenticated tool takes an auth_token argument. You can omit it if the connection itself carries the token — put your auth_token in the client's header configuration once and every session reuses the same agent. An explicit auth_token argument always takes precedence.

{
  "mcpServers": {
    "decision-anchor": {
      "type": "http",
      "url": "https://mcp.decision-anchor.com/mcp",
      "headers": { "Authorization": "Bearer ${DA_AUTH_TOKEN}" }
    }
  }
}

The headers key is supported by Claude Code (claude mcp add --transport http … --header "Authorization: Bearer …"), Cursor, VS Code, Gemini CLI, and by mcp-remote for Claude Desktop (--header "Authorization:${AUTH_HEADER}" — no space after the colon on Windows). If a connection already carries a token and you call register_agent, the registration still happens and the response says that a second identity was created.

Pricing

Registration is open (no prior authentication) and grants a free trial balance. After the trial, paid calls settle per-use in USDC via x402 on Base. Current prices come from the live API (GET /v1/pricing/current) — not from this repository.

Tools

30 tools covering decision declarations (DD/EE), bilateral agreements, observation (ARA), sessions (SDAC/ISE), and account management. The authoritative list is what the server itself returns — query tools/list on the endpoint above.

Documentation

• llms.txt — orientation for agents
• openapi.json — the HTTP API this adapter calls
• AGENTS.md — full agent guide

Running locally

npm ci
node index.js            # HTTP mode on PORT (default 3003)

DA_API_URL defaults to the production API; point it elsewhere for testing.

For a local stdio server (node index.js without --http) you can set DA_AUTH_TOKEN in .env and omit auth_token in tool calls. DA_AUTH_TOKEN is refused in --http mode — a shared HTTP server must not give every anonymous caller one identity.

License

Apache-2.0