# Universal A2A & MCP Tool Discovery, Safe-Proxy & Swarm Router

> Universal A2A & MCP Tool Discovery, Safe-Proxy & Swarm Router is a paid API for AI agents from x402broker.com, paid per call via MPP, $0.01/call, status unknown (last checked 2026-10-21).

Searches and routes to 500+ indexed MCP servers and A2A agent tools through a single meta-router endpoint with token compression and prompt injection protection.

## Facts

- Endpoint: GET https://x402broker.com/v1/broker/execute?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: x402broker.com
- Website: https://x402broker.com
- Canonical page: https://www.zero.xyz/c/x402broker-com-universal-a2a-mcp-tool-discovery-safe-proxy-swarm-router-bf4c5cf4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uuLQp4_smc2zI1s89yUbz

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-com-universal-a2a-mcp-tool-discovery-safe-proxy-swarm-router-bf4c5cf4
```

Example prompt: Search the MCP broker index for any available tools that handle SEC filings or company enrichment — I need to find the right endpoint to route my agent through.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which of 500+ MCP servers or A2A tools best matches a capability need — especially when you want a single stable connection point rather than managing direct connections to dozens of individual MCP servers. Ideal for swarm architectures, agent orchestration pipelines, or when token efficiency and prompt injection safety are priorities.

## Known failure modes

- Empty query string returns a validation error
- No matching tools found for obscure or overly specific queries
- Prompt injection attempt blocked by Prompt-Guard firewall with rejection response
- Payment required (HTTP 402) if x402 micropayment header is missing or invalid
- Timeout if backend MCP index is temporarily unavailable

## 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/broker/execute)

## Output

Returns a list of matching MCP servers or A2A tool endpoints relevant to the capability query, along with routing metadata. Results are token-compressed (up to 85%) and 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-com-universal-a2a-mcp-tool-discovery-safe-proxy-swarm-router-bf4c5cf4/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)