# AgentToolbox MCP Wirecheck

> AgentToolbox MCP Wirecheck is a paid API for AI agents from agnttoolbx.agenttoolbox2026.workers.dev, paid per call via x402, $0.01/call, status down (last checked 2026-10-16).

Validates and inspects a Cloudflare Workers MCP endpoint by performing anonymous read-only protocol discovery against it, checking protocol version compatibility and wire-level conformance.

## Facts

- Endpoint: POST https://agnttoolbx.agenttoolbox2026.workers.dev/v1/products/mcp-wirecheck/invoke?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: down
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agenttoolbox-mcp-wirecheck-a8eb4dd0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZTLiVbjX7QxZqXDfx9Q5k

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 agenttoolbox-mcp-wirecheck-a8eb4dd0 -d '<json body>'
```

Example prompt: Can you wirecheck my MCP endpoint at https://myapp.myworker.workers.dev/mcp to confirm it supports protocol versions 2025-11-25 and 2026-07-28? I own this endpoint and authorize the anonymous read-only discovery.

## When to prefer this

Use this endpoint when you need to validate that a Cloudflare Workers-hosted MCP server is correctly implementing the MCP wire protocol and is discoverable. It is specifically designed for workers.dev MCP endpoints and enforces the URL pattern accordingly. Prefer this over generic HTTP checkers when you need protocol-level MCP conformance results rather than just reachability.

## Known failure modes

- Endpoint URL does not match the required workers.dev/mcp pattern — returns validation error
- Caller does not provide the required authority declaration — request rejected
- Specified protocol versions not in the allowed enum (2025-11-25, 2026-07-28) — schema validation failure
- Target MCP endpoint is unreachable or returns non-MCP responses — probe failure reported
- Payment amount does not match quoted price — payment rejected

## How this service works

Useful tools for agents. Small requests. Concrete results.

## Output

Returns a JSON report describing the MCP endpoint's wire-level conformance, including which protocol versions are supported, what capabilities were discovered via anonymous read-only MCP discovery, and any protocol errors or mismatches detected.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "$schema": "https://json-schema.org/draft/2020-12/schema",
   "required": [
    "endpoint",
    "protocol_versions",
    "authority"
   ],
   "properties": {
    "endpoint": {
     "type": "string",
     "pattern": "^https:\\/\\/[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\\.[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\\.workers\\.dev\\/mcp\\/?$",
     "maxLength": 256
    },
    "authority": {
     "type": "string",
     "const": "I own this endpoint or am authorized to request its anonymous read-only MCP discovery."
    },
    "protocol_versions": {
     "type": "array",
     "items": {
      "enum": [
       "2025-11-25",
       "2026-07-28"
      ],
      "type": "string"
     },
     "default": [
      "2025-11-25",
      "2026-07-28"
     ],
     "maxItems": 2,
     "minItems": 1
    }
   },
   "additionalProperties": false
  },
  "version": {
   "type": "string",
   "const": "0.1.0"
  },
  "agent_id": {
   "type": "string",
   "format": "uuid",
   "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"
  },
  "quote_id": {
   "type": "string",
   "format": "uuid",
   "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"
  },
  "prepared_id": {
   "type": "string",
   "format": "uuid",
   "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$"
  },
  "review_secret_hash": {
   "type": "string",
   "pattern": "^[0-9a-f]{64}$",
   "description": "Optional SHA-256 hex of caller-kept atbr_ secret (32 random bytes). Bound to this paid request; never send the raw secret here."
  },
  "payment_amount_atomic": {
   "type": "string",
   "pattern": "^(0|[1-9][0-9]{0,77})$",
   "description": "Canonical decimal USDC atomic-unit string (6 decimals). Protocol uint256 maximum 115792089237316195423570985008687907853269984665640564039457584007913129639935. No business maximum. Product minimum: 10000. Must equal the exact quoted/signed amount."
  },
  "max_charge_usdc_atomic": {
   "anyOf": [
    {
     "type": "string",
     "pattern": "^(0|[1-9][0-9]{0,77})$",
     "description": "Canonical decimal USDC atomic-unit string (6 decimals). Prot
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agenttoolbox-mcp-wirecheck-a8eb4dd0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agnttoolbx.agenttoolbox2026.workers.dev](https://www.zero.xyz/host/agnttoolbx.agenttoolbox2026.workers.dev/llms.txt)