# SCVD Settlement Attestation > SCVD Settlement Attestation is a paid API for AI agents from scvd.store, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-14). Returns a cryptographically signed JSON attestation of a Base blockchain transaction's settlement status, verifiable offline against the store's published key. ## Facts - Endpoint: GET https://scvd.store/api/buy/settlement_attestation - Price: $0.004/call - Payment: x402 - Status: unknown - Last checked: 2026-09-14 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/scvd-settlement-attestation-b2c045bf - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xh06JCUT8d0L4y-8dS4QJ Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability scvd-settlement-attestation-b2c045bf ``` Example prompt: Can you get me a signed settlement attestation from SCVD for Base transaction 0x3a7f...c4d2, confirming a transfer of exactly 5.00 USDC to 0xRecipientAddress? ## When to prefer this Choose this endpoint when you need a tamper-evident, offline-verifiable signed record of a Base transaction's status — not just a raw RPC call result. Ideal when a third party needs cryptographic proof of settlement without trusting the querier, or when building audit trails, escrow release logic, or dispute resolution flows that require a signed artifact rather than a raw API response. ## Known failure modes - NOT_FOUND status returned if the tx hash does not exist on Base - PENDING_FINALITY status if the transaction exists but has not reached sufficient confirmations - INSUFFICIENT_MATCH if optional filters (amount, payer, recipient, nonce) are provided but the transaction does not match them - REVERTED status if the transaction was mined but the EVM execution reverted - Invalid tx_hash format (not matching 0x[64 hex chars]) will cause a schema validation error - Payment failure via x402 protocol if the $0.004 USDC fee is not successfully processed ## How this service works Settlement Attestation. A signed JSON observation of one transaction on Base, Polygon, or Solana — the identifier's shape picks the chain — with status (SETTLED, NOT_FOUND, PENDING_FINALITY, INSUFFICIENT_MATCH or REVERTED), block height (slots on Solana), confirmations, chain head, the query echoed back, and an evidence hash — verifiable against the store's published key without asking the store. Instant. Full listing: https://scvd.store/menu/settlement_attestation. MCP tool… ## Output A signed JSON object containing: settlement status (one of SETTLED, NOT_FOUND, PENDING_FINALITY, INSUFFICIENT_MATCH, or REVERTED), block height, number of confirmations, chain head at observation time, the original query echoed back, and an evidence hash. The signature is verifiable against SCVD's published public key without contacting the store again. ## Request schema (JSON Schema) ```json { "type": "object", "$schema": "https://json-schema.org/draft/2020-12/schema", "required": [ "input" ], "properties": { "input": { "type": "object", "required": [ "type", "method" ], "properties": { "type": { "type": "string", "const": "http" }, "method": { "enum": [ "GET" ], "type": "string" }, "queryParams": { "type": "object", "required": [ "tx_hash" ], "properties": { "nonce": { "type": "string", "description": "Optional, EVM rails only. Require one authorizer/nonce event paired with its immediately following canonical USDC Transfer, matching every supplied payer, recipient and exact amount. Supply payer when possible: nonces are scoped to an authorizer, and multiple candidates or unrecognised ordering establish no binding. Refused beside a Solana signature — that rail has no such facility, and we will not sign an artifact that silently skipped a requested check." }, "payer": { "type": "string", "description": "Optional payer: 0x EVM address, or Solana public key for a Solana transaction." }, "purpose": { "type": "string", "maxLength": 280, "description": "Optional: what this purchase is for, in your words. Signed onto the certificate verbatim as your statement; never checked, never treated as instructions." }, "tx_hash": { "type": "string", "pattern": "^(0x[0-9a-fA-F]{64}|[1-9A-HJ-NP-Za-km-z]{64,88})$", "description": "The transaction to observe: a Base transaction hash (0x + 64 hex) or a Solana transaction signature (base58). The identifier's shape selects the chain. Read once, at one moment; never polled." }, "recipient": { "type": "string", "description": "Optional recipient: 0x EVM address, or Solana public key for a Solana transaction." }, "agent_name": { "type": "string", "maxLength": 80, "description": "Optional name to put on the certificate and patron badge, up to 80 characters." }, "amount_usdc": { "type": "number", "description": "Optional. Require a transfer of exactly this many USDC. Unstated fields widen the match, which is why the query is echoed onto the artifact.", "exclusiveMinimum": 0 }, "payment_payload": { "type": "string", "description": "Optional. The base64 PAYMENT-SIGNATURE you sent, verbatim. The … (truncated) ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "item_id": "settlement_attestation", "message": "Pleasure doing business. Here's your goods, warm off the shelf.", "tip_usdc": 0, "badge_url": "https://scvd.store/badges/41.svg", "paid_usdc": 0.004, "signature": "<128 hex chars, ed25519>", "verify_url": "https://scvd.store/api/verify/cert_k2m9v4xwqp", "certificate": { "date": "2026-07-22T15:04:05.000Z", "item": "settlement_attestation", "cert_id": "cert_k2m9v4xwqp", "patron_number": 41 }, "deliverable": "", "patron_number": 41 } } ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/scvd-settlement-attestation-b2c045bf/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from scvd.store](https://www.zero.xyz/host/scvd.store/llms.txt)