# x402broker Tool Broker — Universal MCP & A2A Meta-Router

> x402broker Tool Broker — Universal MCP & A2A Meta-Router is a paid API for AI agents from x402broker.com, paid per call via x402 or MPP, $0.01/call, status unknown (last checked 2026-10-20).

Discovers, proxies, and routes queries across 500+ MCP servers and A2A tools via a single connection, with token compression and prompt-injection firewall.

## Facts

- Endpoint: GET https://x402broker.com/v1/tool-broker?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402, MPP
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402broker-tool-broker-universal-mcp-a2a-meta-router-4e8cefb7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_v4ZJgpfLNZ7VtaF5k15s9

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 x402broker-tool-broker-universal-mcp-a2a-meta-router-4e8cefb7
```

Example prompt: Search for MCP or A2A tools that can handle real-time stock price lookups — find me the best available option across all indexed servers using a GET query.

## When to prefer this

Choose this endpoint when an agent needs to discover or route to any of 500+ MCP servers or A2A tools through a single connection, especially when token budget is constrained (85% compression) or when prompt-injection safety is required. Prefer over direct MCP connections when you don't know which specific server has the capability you need.

## Known failure modes

- No matching tool found for the given query — returns empty or null tool list
- Query parameter missing or malformed — returns 400 validation error
- Downstream MCP server or A2A tool unavailable — may return timeout or 502
- Payment not processed — returns 402 Payment Required
- Prompt-Guard firewall blocks suspicious query — returns rejection with firewall notice

## How this service works

Single-connection meta-router indexing 500+ MCP servers & A2A tools with 85% token compression and Prompt-Guard firewall. (Live x402 v2, IETF MPP & MCP endpoint at https://x402broker.com/v1/tool-broker)

## Output

Returns matched tool metadata, proxied tool responses, or routed A2A/MCP results compressed by up to 85% in token size, filtered through a Prompt-Guard firewall to prevent injection attacks.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "query"
 ],
 "properties": {
  "query": {
   "type": "string",
   "minLength": 1,
   "description": "Capability search query (e.g. 'context compression', 'github security', 'sec filings', 'company enrichment') or endpoint URL to verify"
  }
 }
}
```

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402broker-tool-broker-universal-mcp-a2a-meta-router-4e8cefb7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402broker.com](https://www.zero.xyz/host/x402broker.com/llms.txt)