git:20260825.1f7a0f5 to git:20260826.bd93848

---

name: marketplace-invoke

description: Invoke one exact marketplace-listed vendor resource through an approved settlement adapter and return receipt-backed provider readback.

runx:

category: payments

---

# Marketplace Invoke

`marketplace-invoke` is the buyer-facing marketplace skill called through the

existing `runx skill` surface. Paid listing

admission injects the immutable listing, vendor, exact endpoint, vendor price,

demand-side fee, settlement family, and expected receipt class into one Runx

run before its quote is fingerprinted. Callers supply only the live settlement

signal, the matching bounded authority, and a stable retry identity. Hosted

receipt custody verifies the returned inner receipt and seals the outer

execution as a mediated composite receipt.

The skill is rail-neutral at its boundary. `settlement_family` selects an

explicit adapter branch; x402 is the first implementation. Stripe and future

rails add sibling branches while preserving the listing, vendor, authority,

result, and composite-receipt semantics. Provider SDKs, wallets, credentials,

settlement recovery, and database state remain in Runx Hosted.

## Composes

<!-- Generated from the native execution closure; run pnpm core-skills:composes:generate. -->

- `x402-pay#pay`

## Operator guide

Use this skill through a paid endpoint listing after marketplace discovery.

Supply the exact settlement signal returned for that resource, a complete

parent maximum equal to the listing's vendor price, and an idempotency seed

stable across every retry. `marketplace_offer` is reserved for hosted admission;

a caller-supplied value is refused. Keep large inputs behind artifact references.

The x402 branch delegates to `x402-pay`, which owns the single provider-effect

approval, exact external V2 validation, durable signed-payload retry, transaction

Stop if the family is unsupported, the endpoint differs from the authority or

signal, terms drift, provider readback is incomplete, or the inner receipt is not

available in hosted custody. A refusal or uncertain effect remains visible in the

receipt and must be retried only with the same idempotency seed.