# agentx.sale WebMCP Agent-Compatibility Checker

> agentx.sale WebMCP Agent-Compatibility Checker is a paid API for AI agents from agentx.sale, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-21).

Checks whether a website exposes a WebMCP tool surface that AI agents can call, returning an inventory of tools, schema-hygiene findings, and a readiness verdict

## Facts

- Endpoint: GET https://agentx.sale/x402/webmcp-check?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentx-sale-webmcp-agent-compatibility-checker-214b0034
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lTDKhGAvgmZlYmcIr5gRv

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 agentx-sale-webmcp-agent-compatibility-checker-214b0034
```

Example prompt: Can you check whether stripe.com exposes a WebMCP tool surface that AI agents can call — I want to see the tool inventory, any schema issues, and whether it passes the readiness verdict?

## When to prefer this

Choose this endpoint when you need to specifically verify WebMCP protocol compatibility and tool discoverability for a given domain, rather than general agent-readiness (use the Site Agent-Readiness Verdict Card for broader checks) or x402 payment compliance (use x402 Doctor for that). Best when you want a focused inventory of callable tools plus schema lint findings.

## Known failure modes

- Host not reachable — domain does not resolve or times out
- No WebMCP surface detected — site does not expose any WebMCP endpoint
- Schema parsing error — the site's WebMCP manifest is malformed beyond recovery
- Rate limit or payment failure — x402 payment not processed
- Invalid host parameter — malformed or missing host query parameter

## How this service works

WebMCP agent-compatibility check: does a website expose a WebMCP tool surface agents can call? Inventory, schema-hygiene findings and readiness verdict

## Output

Returns a structured report containing: the inventory of WebMCP tools exposed by the target website, schema hygiene findings identifying any malformed or non-compliant tool definitions, and an overall agent-readiness verdict indicating whether the site is properly configured for AI agent tool calling.

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "host": "example.com",
  "tools": [],
  "webmcp_ready": false
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentx-sale-webmcp-agent-compatibility-checker-214b0034/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentx.sale](https://www.zero.xyz/host/agentx.sale/llms.txt)