# 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 and routes queries across 500+ indexed MCP servers and A2A tools with token compression and prompt-injection firewall protection.

## Facts

- Endpoint: GET https://preflight.agentdiet.dev/v1/tool-broker?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-9c3f626f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FfP4cY2MHooZDWZMI8ANj

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-9c3f626f
```

Example prompt: Search the tool broker for any MCP servers or A2A agents that handle SEC filings or company enrichment — I want to find what's available so I can wire it into my pipeline.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which MCP servers or A2A tools support a given capability at runtime, rather than hardcoding tool references. Especially useful for swarm orchestration, agent pipelines that need to expand their toolset on demand, or when you need safety-screened (prompt-injection-filtered) access to a broad index of 500+ external tools with minimal token overhead.

## Known failure modes

- Empty or too-broad query returns low-relevance or no matches
- Queried endpoint URL not found in the index returns empty or not-found result
- Rate limiting or payment failure (HTTP 402) if x402 micropayment not properly configured
- Query string too short (minLength:1 not met) returns validation error
- Index lag means newly registered 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/v1/tool-broker)

## Output

Returns a list of matched MCP servers or A2A tools relevant to the query, including compressed metadata (85% token reduction), endpoint details, safety screening status from the Prompt-Guard firewall, and routing information for direct agent use.

## 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-9c3f626f/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)