# X402-BROKER MCP Gateway

> X402-BROKER MCP Gateway is a paid API for AI agents from mcp-gateway.agentdiet.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-22).

Routes agent queries across 31,390+ MCP servers, x402 APIs, and A2A agents, settling payments in USDC on Base via the x402 protocol.

## Facts

- Endpoint: GET https://mcp-gateway.agentdiet.dev/v1/x402-gateway?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-broker-mcp-gateway-63abf63b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_041VMHgRkqQ7Lyq5uvCvW

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 x402-broker-mcp-gateway-63abf63b
```

Example prompt: Search the MCP gateway for a tool that can get me live stock prices and run it with the query 'AAPL current price' — pay with USDC on Base if needed.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover and invoke capabilities across a large pool of MCP servers, x402-gated APIs, or A2A agents without managing individual integrations or payment flows. It is especially useful when the target tool is not known in advance and needs to be brokered at runtime, and when USDC micropayment settlement on Base is acceptable.

## Known failure modes

- Insufficient USDC balance on Base — payment settlement fails
- No matching MCP server or tool found for the given query
- Invalid input schema — missing required 'type' or 'method' fields
- Upstream MCP server or x402 API is unavailable or times out
- Query parameter missing or malformed, resulting in empty or error response

## How this service works

Deterministic B2A/A2A/MCP/x402/MPP/L402 execution and intelligence node at https://mcp-gateway.agentdiet.dev settling in USDC on Base.

## Output

Returns a JSON object with a 'data' field containing the tool or API response, a 'status' field ('ok' on success), and an 'roi_proof' object including a compression_ratio_pct metric indicating efficiency of the response.

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {},
  "status": "ok",
  "roi_proof": {
   "compression_ratio_pct": 91.4
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-broker-mcp-gateway-63abf63b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mcp-gateway.agentdiet.dev](https://www.zero.xyz/host/mcp-gateway.agentdiet.dev/llms.txt)