# Deep Protocol & Security Audit for A2A/MCP/x402 Endpoints

> Deep Protocol & Security Audit for A2A/MCP/x402 Endpoints is a paid API for AI agents from assay.agentdiet.dev, paid per call via MPP or x402, $0.005/call, status unknown (last checked 2026-10-21).

Performs a cryptographic pre-flight security audit, schema conformance check, and TDQS reputation verification on a given A2A, MCP, or x402 endpoint, returning a grade and score.

## Facts

- Endpoint: GET https://assay.agentdiet.dev/v1/audit?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP, x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: assay.agentdiet.dev
- Website: https://assay.agentdiet.dev
- Tags: x402
- Canonical page: https://www.zero.xyz/c/assay-agentdiet-dev-deep-protocol-security-audit-for-a2a-mcp-x402-a5f18724
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Vjz8_1D0n7ibC_-I_zH-5

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 assay-agentdiet-dev-deep-protocol-security-audit-for-a2a-mcp-x402-a5f18724
```

Example prompt: Can you run a deep security and protocol audit on https://x402broker.com — I want to know its grade and conformance score before I let my agent connect to it.

## When to prefer this

Use this endpoint when you need a quick, automated security and protocol compliance check on any A2A, MCP, or x402 endpoint before connecting to it, integrating it into an agent workflow, or routing payments through it. It is especially valuable for pre-flight vetting of unfamiliar third-party agent services, payment processors, or MCP servers where cryptographic conformance and TDQS reputation matter. Prefer it over manual inspection or generic HTTP health checks when you need a structured grade and score rather than raw connectivity data.

## Known failure modes

- Target URL is unreachable or returns no response — audit may fail or return a low score
- Target is not an A2A/MCP/x402 endpoint — may result in conformance errors or invalid grade
- Malformed or missing target parameter — request rejected with validation error
- Rate limiting or payment failure — endpoint returns 402 or throttle error
- Target endpoint actively blocks external probing — incomplete audit results

## How this service works

Live A2A & MCP endpoint security auditor, Tool Definition Quality Score (TDQS) certifier, prompt-injection scanner, and cryptographic trust oracle.

## Output

Returns a JSON object containing the audit status (e.g. pass/fail), a letter-style security grade (e.g. A, B, C), a numeric score (integer), and the target URL that was audited. This gives a concise, actionable security posture summary for the queried endpoint.

## 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",
      "POST"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "target": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "dossier": {
   "grade": "A",
   "score": 95,
   "target": "https://example.com"
  },
  "receipt": "asr_rcpt_sample",
  "verdict": "allow"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/assay-agentdiet-dev-deep-protocol-security-audit-for-a2a-mcp-x402-a5f18724/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from assay.agentdiet.dev](https://www.zero.xyz/host/assay.agentdiet.dev/llms.txt)