# Agent Embassy Assurance Check

> Agent Embassy Assurance Check is a paid API for AI agents from aemb.pro, paid per call via x402, $0.25/call, status unknown (last checked 2026-10-11).

Runs an authorization and proof-of-execution check on an agent action, returning a verdict, decision, and tamper-evident receipt.

## Facts

- Endpoint: POST https://aemb.pro/v1/assurance/check?utm_source=zero.xyz
- Price: $0.25/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-embassy-assurance-check-2d415de6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__o6bW25hqyFUrIJy8Obup

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 agent-embassy-assurance-check-2d415de6 -d '<json body>'
```

Example prompt: Run an assurance check on my agent's last action for account 0x1111111111111111111111111111111111111111 and give me the verdict, decision, and receipt ID so I have proof of what happened.

## When to prefer this

Choose this endpoint when you need a cryptographically traceable authorization and proof-of-execution record for an AI agent action — especially in multi-agent workflows where liability boundaries, compliance auditing, or payment-gated authorization are required. Prefer it over generic logging when you need a structured verdict and receipt that downstream systems or auditors can verify.

## Known failure modes

- Invalid or missing account address returns an error response
- Unauthorized action may return a DENY decision rather than an error
- Malformed request body causes a 400-level response
- Payment not received (x402 protocol failure) returns 402 Payment Required
- Service unavailability returns a 5xx error with no receipt issued

## How this service works

Agents pay for work and prove what happened.

## Output

Returns a JSON object with: tool name ('assurance_check'), the authorization chain steps (request, authorization, action, proof, liability_boundary), overall status, the agent account address, a pass/fail verdict, a decision string (e.g. ALLOW_WITH_RESTRICTIONS), a unique receipt_id, and a receipt_version string. Together these form a verifiable record of what the agent did and whether it was authorized.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "action": {
   "type": "string",
   "description": "The action the agent intends to take, e.g. 'transfer' (required, max 200 chars)"
  },
  "context": {
   "type": "string",
   "description": "Optional free-text context for the assessment (truncated to 2000 chars)"
  },
  "amount_usdc": {
   "type": "string",
   "description": "Amount at stake, as a positive decimal string, e.g. '0.25'"
  },
  "idempotency_key": {
   "type": "string",
   "description": "Idempotency key: UUID v4, client-generated, one per logical request. Replaying the same key on this tool returns the original receipt — the action is not re-run, and the first request's receipt wins even if you resend different inputs. Published example keys are rejected. Keys are scoped per tool and per payer account: a key never returns another wallet's receipt."
  },
  "provider_endpoint": {
   "type": "string",
   "description": "HTTPS URL of the provider to assess (max 2000 chars; no credentials in URL)"
  },
  "permissions_requested": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "description": "Permissions the action needs, e.g. ['spend']. Non-empty array, max 50 entries; each entry truncated to 200 chars"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tool": "assurance_check",
  "chain": [
   "request",
   "authorization",
   "action",
   "proof",
   "liability_boundary"
  ],
  "status": "complete",
  "account": "0x1111111111111111111111111111111111111111",
  "verdict": "pass",
  "decision": "ALLOW_WITH_RESTRICTIONS",
  "receipt_id": "emb_pqr678",
  "receipt_version": "embassy-receipt/2"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-embassy-assurance-check-2d415de6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from aemb.pro](https://www.zero.xyz/host/aemb.pro/llms.txt)