@atrib/verify-mcp

MCP server exposing the atrib-verify cognitive primitive. It verifies counterparty handoff evidence before a receiving agent signs follow-up work that cites those records through informed_by.

The package is read-only. It accepts caller-supplied evidence, returns accepted and rejected hashes, and leaves the follow-up signing step to atrib-emit or normal wrapped tool calls.

Install

npm install @atrib/verify-mcp

Tool surface

Host-specific tool names vary. The MCP tool itself is named atrib-verify:

mcp__atrib-verify__atrib-verify({
  packet?: unknown,
  records?: unknown[],
  claims?: unknown[],
  required_record_hashes?: string[],
  trusted_creator_keys?: string[],
  allowed_context_ids?: string[],
  require_body?: boolean,
  require_body_commitment?: boolean,
  require_log_inclusion?: boolean,
  log_public_key_b64?: string,
  max_age_ms?: number,
  now_ms?: number,
})

Evidence

packet, records, and claims accept the same evidence shapes as @atrib/verify:

• D062 local mirror envelopes: { record, proof?, _local?: { content?, args?, result? } }
• Private continuation packets: { required_record_hashes, records, trusted_creator_keys?, allowed_context_ids? }
• Bare records for signature-only checks, when body or proof checks are not required

The response returns accepted hashes plus compact per-claim evidence:

{
  "primitive": "atrib-verify",
  "all_accepted": true,
  "accepted_record_hashes": ["sha256:..."],
  "accepted": [
    {
      "record_hash": "sha256:...",
      "accepted": true,
      "signature_ok": true,
      "signer_trusted": true,
      "context_allowed": true,
      "body": {
        "args_hash_present": true,
        "args_hash_ok": true,
        "result_hash_present": false,
        "result_hash_ok": null
      }
    }
  ],
  "rejected": []
}

Behaviors

• Read-only: never signs records, submits to the log, or mutates the local mirror.
• Caller-supplied evidence: does not fetch from the public log or retrieve archive bodies.
• Verifier-backed: delegates signature, trust, body-commitment, inclusion, freshness, and context checks to @atrib/verify.
• Handoff-oriented: accepted hashes are the values the receiving agent can cite through informed_by when it signs follow-up work.
• Explicit rejection: failed claims stay visible in rejected instead of disappearing from the response.

Wire-up

Run it through npx from an MCP host:

{
  "mcpServers": {
    "atrib-verify": {
      "command": "npx",
      "args": ["-y", "@atrib/verify-mcp"]
    }
  }
}

Or install it globally. The package exposes the atrib-verify binary:

npm install -g @atrib/verify-mcp
atrib-verify

Local Development

From a checkout of the atrib monorepo:

pnpm --filter @atrib/verify-mcp build
pnpm --filter @atrib/verify-mcp test
pnpm --filter @atrib/verify-mcp start

For local MCP host testing without npm:

{
  "mcpServers": {
    "atrib-verify": {
      "command": "node",
      "args": ["/absolute/path/to/atrib/services/atrib-verify/dist/main.js"]
    }
  }
}

Relationship to @atrib/verify

@atrib/verify-mcp depends on @atrib/verify for verifier semantics. The MCP package owns the agent-facing schema, stdio transport, and compact response shape.

Status

Public package for cognitive primitive #7. It depends on @atrib/verify for verifier semantics and keeps the MCP surface read-only.

License

Apache-2.0.