For Agents

One feed, one door, no checkout of ours

An agent can read every piece the 21 houses publish, and the 3,081 sizes they declare, from four places. None of them sells anything: every offer carries the house's own page, and a person buys there.

Endpoints

• GET /agent/catalog.json: every piece with declared sizes, grouped by house, as schema.org Product and Offer in the agent-feed@1 shape, with no checkout block.
• GET /houses/<house>/offers.json: the house's offers@1 file, byte for byte. For example /houses/thelinks/offers.json.
• GET /llms.txt: this page, in plain text.
• POST /mcp: MCP over JSON-RPC 2.0, one message per request, no session, no key.

The four tools

• search: query, and optionally house, buyable, rights and limit. Returns call numbers.
• get_piece: house and slug. The facts, the picture, the house page and every declared offer.
• list_houses: the 21 houses, their hosts and counts, and the offers file each count came from.
• offers_for_piece: house and slug. Only the declared rows, with buyAt, the house URL.

There is no fifth tool. An agent that wants to buy hands the person the buyAt URL.

The call number printed on every card, for example TheLinks/allan-william-inglis, is the house and slug that get_piece takes.

An example call

curl -s https://provenance-catalogue.vercel.app/mcp \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call",
       "params":{"name":"search","arguments":{"query":"hokusai wave","buyable":true}}}'

Errors

A tool error comes back as a result with isError: true and a stable code: INVALID_ARGUMENT, UNKNOWN_HOUSE, UNKNOWN_PIECE. Over 60 calls a minute from one address returns HTTP 429 with RATE_LIMITED.