agent-passport-access-shim

An adapter that emits a signed AccessReceipt for each governed MCP tools/call. Instrument a tool handler, and every call against a configured source produces a receipt carrying the tool name, request and response digests, source id, timestamp, and signer identity. A requester identity is recorded only when the caller supplies one.

This is proof of governed access; access is not contribution, and contribution is not value.

What it reuses

The shim defines no cryptography of its own. Signing is the agent-passport-system SDK's sign() over canonicalize(), verification is the SDK's verify() over the same canonical bytes, and the signer DID is the SDK's createDID(). The shim maps a tools/call onto those primitives and nothing more.

Receipt fields

| Field | Meaning | |---|---| | profile | aps:access-receipt:v1 | | receiptId | acr_ + digest of signer, source, tool, time, request | | tool | MCP tool name | | source_id | Configured source the call ran against | | request_digest | SHA-256 of the canonical request arguments | | response_digest | SHA-256 of the canonical response | | signer_did | DID derived from the signer public key | | signer_public_key | Ed25519 public key (hex) | | requester | Present only when the caller supplied a requester identity | | accessed_at | ISO 8601 timestamp | | signature | Ed25519 signature over the canonical receipt (SDK sign) |

Usage

import { instrumentToolHandler, verifyAccessReceipt } from 'agent-passport-access-shim'
import { generateKeyPair } from 'agent-passport-system'

const signer = generateKeyPair()
const receipts = []

const governed = instrumentToolHandler('search_matches', searchHandler, {
  sourceId: 'crm://accounts',
  signerPublicKey: signer.publicKey,
  signerPrivateKey: signer.privateKey,
  onReceipt: (r) => receipts.push(r),
  getRequester: (_args, extra) => extra?.requester, // omitted when absent
})

await governed({ query: 'acme' }, { requester: 'did:aps:...' })
verifyAccessReceipt(receipts[0]) // { valid: true, signatureValid: true, errors: [] }

License

Apache-2.0.