PEPTIDES X402 · SETTLEMENT AFTER THE GATE · 2026-09-17

Peptides x402

Agent-to-Agent (A2A) + Model Context Protocol (MCP) hub for peptides.

AI agents for authorized trading partners. Not marketing. Not advertising.

The payments door of the A2A Peptides family: settlement after the gate, and the per-resolve meter on the registry's truth tools. An order intent settles in USDC on Base; the receipt is signed and carries the reason code and the rule-set version the gate returned.

x402
PROTOCOL · VERSION 2 · SCHEME EXACT
USDC
ASSET · BASE MAINNET (EIP155:8453)
1
GATE DECISION ON EVERY RECEIPT · REASON CODE + RULE-SET VERSION

A key here is a signature, not a wallet. Research-use stock is not listed and not sold.

§01 · WHAT THIS IS

What this is

x402 is 100% of the design: settlement after the gate, and a per-resolve meter on the registry's truth tools. An order intent created by the door settles here in USDC on Base; the receipt is signed and carries the reason code and the rule-set version the gate returned, so a settlement without a gate decision cannot exist.

The meter prices a resolve of the registry's truth tools (substance record, pathway status, compounding eligibility) per call; the reads on the hub page and the kit stay open.

§02 · THE DOOR

The door

  • GET /api — the paid call: without payment a 402 offer (x402 v2, scheme exact, USDC on Base); with a payment signature the settled answer and a signed receipt. The receive address of record and the facilitator credentials are set on the door by the operator's hand; until they are set, /api answers 402 with the offer shape and no settlement is possible.
  • GET /x402/receipt/{nonce} — resolve a receipt, forever.
  • GET /x402/jwks.json — the receipt signing key.
  • Order intents — created by create_order_intent on the door at mcp.a2a-peptides.ai/mcp; the intent carries decision_id, reason_code and rule_set_version.
§03 · RECEIPTS

Receipts

Every receipt is signed and carries: the intent, the presentation identifiers, the amount and asset, the settlement transaction, the decision_id, the reason_code and the rule_set_version. A receipt resolves at its nonce for as long as the door stands.

§04 · CONTACT

Contact

A person reads the form.

The form is the only human door on this surface.