RSL DECLARATIONS · SIGNED EVIDENCE · HTTP X402

The AcqPath HTTP x402 purchase contract

Quote first, private claim second, signed payment third. This is a multi-step report flow, not a generic one-call paid MCP tool.

Separate stock marketplace endpoint

SUPPORTED SECURE MODE: tested official TypeScript/Node x402 2.25.0 and Python x402 2.22.0 with the AcqPath SIWX adapter on /v1/rights/preflight; unchanged signer and random nonce, recommended when payer-signed request binding is required. SUPPORTED STOCK WIRE MODE: the same official stock clients without SIWX, custom nonce, signer or buyer hook on /v1/rights/preflight/x402, fresh only, 0.02 USDC. Stock binds one request atomically at first valid use; it does not sign the POST body in advance. Zero-config compatibility outside this fixed stock endpoint, stock SIWX-only hooks, Payments MCP and generic paid proxies are not supported by this integration.

Same signed authorization plus same normalized request recovers the existing stock result; changed input or another route is rejected after binding. A pre-use leaked stock authorization can be raced for another same-priced request. Keep signed HTTP requests private. Never create a replacement authorization after an uncertain payment.

Stock endpoint, JSON, official TypeScript/Python and recovery

Rights Gateway: select the paid operation

LIVE Base USDC pricing: Secure Preflight 0.02 fresh / 0.05 deep per prepared settled report; Ingestion Gate 0.04 + 0.02 per distinct URL fresh or 0.06 + 0.04 per URL deep (1–4 eligible public HTTPS URLs); Revalidation 0.03 fresh / 0.06 deep. Stock x402 stays fresh-only 0.02 and reviewed-only. No new subscription, prepaid, API-key billing or invoicing plan is active.

A Secure Preflight may offer a disclosed paid UNKNOWN or no-declaration diagnostic after meaningful public-source observation. An outage with no usable source observation, invalid URL or exhausted safety budget is not billable Preflight. Gateway pricing covers a bounded observation attempt after verified authorization. UNKNOWN never authorizes content use.

Gateway limits, prices and workflow Complete TypeScript and Python examples

Current supported buyer integration

Fresh 0.02 USDC; deep 0.05 USDC on Base eip155:8453. Pin the exact recipient, USDC asset, fee and Ed25519 verification key. The adapter verifies offer, report, receipt and delivery binding. Private checkpoint files retain bearer authorizations and are not application-level encrypted; protect them with private ACLs and encrypted storage.

Install, call and verify: complete TS/Python guide Public buyer journey

1. Install the tested dependencies

Node 22.16+: @x402/core, @x402/evm, @x402/fetch, @x402/extensions 2.25.0 and viem 2.56.3. Python 3.12/3.13: x402 2.22.0, httpx 0.28.1, deliberate ABNF 2.2.0 pin. Use the supplied manifest/requirements with the source adapter.

Installation and complete examples

2. Authorize exactly one logical request

Check live coverage → call POST /v1/rights/preflight through the AcqPath SIWX adapter → verify the prepared signed offer → preserve the unchanged official payment authorization privately → complete SIWX prebinding/authorization → receive the verified report. Use the same operation ID, input and private store after ambiguity; never create a replacement payment.

The adapter owns PAYMENT-SIGNATURE, SIGN-IN-WITH-X, X-AcqPath-Payment-Intent and X-AcqPath-Request. Do not manually replace a nonce or provide these headers. The extra SIWX signature binds the selected order and exact payment.

3. Verify delivery and recover

A successful paid result is returned only after the adapter verifies the Ed25519 report, signed settlement receipt, input/purpose, amount and transaction-bound delivery proof. HTTP 200 with available:false and charge_micro:0 is unpaid, not a verified paid report.

On timeout, use the SAME operation ID, input and private directory. Preserve unresolved authorizations; an uncertain 503 needs existing operator reconciliation. Never delete pending state or start another payment to clear an error. A verified receipt is not independent on-chain finality.

Recovery

Legacy boundary

The older quote/claim SDK still serves existing integrations. Its report URL and encrypted store are separate from the public SIWX adapter. Existing legacy behavior does not require new buyers to implement a bound EIP-3009 nonce. UNKNOWN is not permission; a report is not a license.