# 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 to find, verify, and route to the right capability, with built-in prompt-injection firewall and token compression.

## Facts

- Endpoint: GET https://preflight.agentdiet.dev/v1/a2a-mesh?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-978699c0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xQPGsVUKuPJnYBO-pJukR

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-978699c0
```

Example prompt: Can you search the A2A and MCP tool index for anything that handles SEC filings or company enrichment, and tell me which servers are available?

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which MCP server or A2A tool to call for a given capability, rather than hard-coding a specific tool. Also useful for verifying whether a third-party endpoint is safe before routing traffic to it, or when operating a multi-agent swarm that needs to minimize token overhead via compressed routing.

## Known failure modes

- No matching tools found for the query — returns empty result set
- Endpoint URL submitted for verification is unknown — returns unverified/unknown status
- Query string is missing or empty — returns 400 validation error
- Downstream MCP index temporarily unavailable — may return 503 or partial results
- Ambiguous query returns low-confidence or mixed-relevance matches

## 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/v1/a2a-mesh)

## Output

Returns a list of matched MCP servers and A2A tools relevant to the query, with tool metadata, safety status from the Prompt-Guard firewall, and token-compressed routing information. May also return a verification verdict if an endpoint URL was submitted.

## 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-978699c0/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)