# 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 preflight.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 tools by capability query, returning compressed, firewall-screened tool metadata for agent routing and swarm orchestration.

## Facts

- Endpoint: GET https://preflight.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: preflight.agentdiet.dev
- Website: https://preflight.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/preflight-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-0e0ce374
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jsvOishClfcsh-sMP5aCn

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 preflight-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-0e0ce374
```

Example prompt: Search the MCP tool index for servers that can handle 'company enrichment' — I need to find and safely route to one with prompt-injection protection enabled.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover, evaluate, or route to MCP servers or A2A tools at runtime without maintaining its own tool registry — especially when token budget is a concern (85% compression) or when untrusted tool payloads need firewall screening before use.

## Known failure modes

- Empty or vague query returns no useful matches
- Queried endpoint URL not found in index returns a null or unverified result
- Prompt-Guard firewall flags the query itself as suspicious
- Rate limit or payment failure (HTTP 402) when x402 credits are exhausted
- Index lag means newly added MCP servers may not appear immediately

## 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://preflight.agentdiet.dev/api/mcp/audit)

## Output

A structured response listing matching MCP servers or A2A tools from the 500+ tool index, with compressed descriptions (up to 85% token reduction), Prompt-Guard firewall screening results, routing metadata, and any relevant capability scores or endpoint verification details.

## 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/preflight-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-0e0ce374/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from preflight.agentdiet.dev](https://www.zero.xyz/host/preflight.agentdiet.dev/llms.txt)