# 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 x402-audit.agentdiet.dev, paid per call via MPP, $0.01/call, status unknown (last checked 2026-10-21).

Searches and routes queries across 500+ MCP servers and A2A tools via a single meta-router connection with token compression and prompt injection firewall

## Facts

- Endpoint: GET https://x402-audit.agentdiet.dev/v1/mcp-router?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: x402-audit.agentdiet.dev
- Website: https://x402-audit.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/x402-audit-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-0a229383
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KrD8Yz2Zc5oesHexo-JXV

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-audit-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-0a229383
```

Example prompt: Search the MCP tool registry for any servers that handle SEC filings or company enrichment, and route me to the best match.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which MCP server or A2A tool to use for a given capability, rather than hardcoding a specific tool. It is especially useful in multi-agent swarms or orchestration pipelines where the right downstream tool must be selected at runtime. Prefer this over manually curated tool lists when you need coverage across 500+ indexed servers with built-in safety filtering.

## Known failure modes

- Empty query string returns validation error
- No matching tools found for obscure query returns empty result set
- Queried endpoint URL fails SLA check and is flagged as non-compliant
- Prompt injection attempt blocked by Prompt-Guard firewall
- Payment not processed via x402 returns HTTP 402 with payment details

## 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://x402-audit.agentdiet.dev/v1/mcp-router)

## Output

Returns a list of matching MCP server entries or A2A tool descriptors relevant to the search query, with capability metadata in compressed form, enabling the calling agent to identify and connect to the appropriate downstream tool or endpoint.

## 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/x402-audit-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-0a229383/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-audit.agentdiet.dev](https://www.zero.xyz/host/x402-audit.agentdiet.dev/llms.txt)