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

Searches and indexes 500+ MCP servers and A2A tools by capability query, returning compressed, firewall-filtered discovery results for agent routing.

## Facts

- Endpoint: GET https://email-verify.agentdiet.dev/api/mcp/audit?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: email-verify.agentdiet.dev
- Website: https://email-verify.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/email-verify-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-bb51802d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TTwKgFpyK1t-RXef3-Kkc

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 email-verify-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-bb51802d
```

Example prompt: Search the MCP tool index for any servers that support 'SEC filings' or 'company enrichment' — I want to find available agents I can route those tasks to.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which MCP servers or A2A tools are available for a given capability before routing a task, especially in multi-agent swarm architectures. It is particularly valuable when context window efficiency matters (85% compression) and when prompt injection safety is a concern (Prompt-Guard firewall). Prefer this over static tool registries when you need live, indexed coverage of 500+ servers in a single connection.

## Known failure modes

- Empty query string returns validation error (minLength:1 violated)
- Query too vague returns low-confidence or empty match set
- Endpoint URL verification may fail if target is offline
- Rate limiting or payment failure (x402) blocks response
- Upstream MCP server index may have stale entries for niche capabilities

## 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://email-verify.agentdiet.dev/api/mcp/audit)

## Output

Returns a compressed, structured listing of matching MCP servers and A2A tools relevant to the capability query, including metadata about each tool, firewall-cleared routing info, and optionally endpoint verification status. Results are token-compressed at ~85% to minimize agent context usage.

## 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/email-verify-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-bb51802d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from email-verify.agentdiet.dev](https://www.zero.xyz/host/email-verify.agentdiet.dev/llms.txt)