---
title: "A2A x402-Extension Mandate Validator"
method: POST
path: "/v1/tools/validate_a2a_x402_mandate"
tags: ["TODO_TAGS_REVIEW", "TODO_AP2_EXPORT_REVIEW"]
---

# A2A x402-Extension Mandate Validator

`POST /v1/tools/validate_a2a_x402_mandate`

## Request

- Base URL: `https://ainumbers.co`
- URL: `https://ainumbers.co/v1/tools/validate_a2a_x402_mandate`
- Auth: none declared

Validates the A2A x402 extension (Coinbase/MetaMask/Ethereum Foundation) that carries crypto-payment authority inside an AP2 mandate: extension declaration in the A2A agent card, payment-authority scope, settlement-rail binding, exact-scheme x402 PaymentPayload lint, and mandate-to-payment-leg consistency. PASS/WARN/FAIL verdict + execution_hash. Educational/simulation.

**Tool URL:** https://ainumbers.co/chaingraph/art-31-a2a-x402-extension-mandate-validator.html

## Request body

- object
  - `agent_card` unknown, required
  - `mandate_cap` unknown, required
  - `payment_payload` unknown, required

## Response `200`

Successful tool execution result

- object
  - `checks` object[]
    - `code` string
    - `note` string
    - `status` string
  - `extension_declared` boolean
  - `fail_count` integer
  - `pass_count` integer
  - `payment_authority_scope_present` boolean
  - `settlement_rail_bound` boolean
  - `verdict` string
  - `warn_count` integer

---

[API](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite.md) · [All operations](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite/llms.txt) · [OpenAPI document](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite/revisions/b462e4f5bb28?raw)