# 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 serp-extract.agentdiet.dev, paid per call via MPP, $0.01/call, status unknown (last checked 2026-10-23).

Searches and routes to 500+ indexed MCP servers and A2A tools via a single meta-router endpoint with token-compressed results and prompt injection firewall.

## Facts

- Endpoint: POST https://serp-extract.agentdiet.dev/v1/tool-search?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Provider: serp-extract.agentdiet.dev
- Website: https://serp-extract.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/serp-extract-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-28ca0209
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1Xf1U5xiOJg0f1JLHvLzq

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 serp-extract-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-28ca0209 -d '<json body>'
```

Example prompt: Search the MCP and A2A tool index for anything that handles 'company enrichment' — I want to see what tools are available and their capabilities, compressed so they fit in my context.

## When to prefer this

Choose this endpoint when you need to discover which MCP server or A2A tool can handle a specific capability without manually browsing hundreds of registries. Prefer it over individual tool directories when you want token-compressed results, need a prompt-injection-safe proxy layer, or are routing tasks dynamically across a swarm of agents that need to pick tools at runtime.

## Known failure modes

- Empty query string returns validation error
- No matching tools found returns empty result set
- Malformed query may return low-relevance results
- Payment required (HTTP 402) if x402 micropayment header is missing
- Rate limiting if too many calls made without idempotency key

## 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://serp-extract.agentdiet.dev/v1/tool-search)

## Output

Returns a compressed list of matching MCP servers and A2A tools ranked by relevance to the query, including endpoint details, capability descriptions, and token-pruned metadata — with prompt injection guard applied to all results.

## 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/serp-extract-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-28ca0209/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from serp-extract.agentdiet.dev](https://www.zero.xyz/host/serp-extract.agentdiet.dev/llms.txt)