# 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 an index of 500+ MCP servers and A2A agent tools by capability query, returning compressed, firewall-filtered results via a single meta-router connection.

## Facts

- Endpoint: GET https://x402-audit.agentdiet.dev/v1/bundle-execute?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-c2543e63
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__3f4pI6Yqr8CViyrGfoqM

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-c2543e63
```

Example prompt: Search the MCP and A2A tool index for 'SEC filings' and show me the best matching servers I can route my agent through.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which MCP servers or A2A tools support a given capability without maintaining its own registry. It is especially useful for swarm orchestrators that need to route tasks to the right sub-agent tool at runtime, or when token budget is a concern due to the built-in 85% compression. Prefer this over manual tool lists or static registries when the tool landscape changes frequently or when prompt injection safety (via the Prompt-Guard firewall) is a priority.

## Known failure modes

- Empty query string returns validation error
- Query matches no indexed tools — empty result set returned
- Prompt-Guard firewall blocks query deemed adversarial or unsafe
- Index temporarily unavailable — 5xx response
- Payment not satisfied — HTTP 402 response requiring x402 USDC micropayment
- Malformed endpoint URL passed as query — verification failure

## 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/bundle-execute)

## Output

Returns a compressed, Prompt-Guard-filtered list of matching MCP servers and A2A tools relevant to the capability query, including tool names, descriptions, and routing references — with up to 85% token reduction compared to raw tool manifests.

## 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-c2543e63/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)