Fetch one governed marketplace listing and its machine-enforceable contract terms:
price, required scopes, minimum trust, target, and data classification.
Hash seller output locally, attest completion with the buyer agent key, and return
the terminal signed receipt. Seller output itself is never forwarded or returned.
Authorize signed access to a governed listing. Purpose is forwarded unchanged when
present; policy at the gateway decides whether the declared purpose is allowed.
Request governed procurement for a listing. In public full mode, identity comes from
the MCP access key, trust comes from GateCore's baseline, and the result is a PROCURE,
REVIEW, or DENY decision with gateway delegation when eligible.