# 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+ MCP servers and A2A tools via a single meta-router endpoint with token compression and prompt firewall protection

## Facts

- Endpoint: POST https://serp-extract.agentdiet.dev/v1/mcp-gateway?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-73f8ff5f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_K9nQduf2mrK38URQYKcFO

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-73f8ff5f -d '<json body>'
```

Example prompt: Search the MCP tool registry for available agents that handle SEC filings and company enrichment, then return the best matching endpoints with their capabilities.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which MCP servers or A2A tools are available for a given capability without hardcoding individual endpoints. Ideal for multi-agent swarms that need a single connection point to route across hundreds of tools, or when token budget is constrained and 85% compression is needed. Also use it to verify whether a third-party MCP endpoint is safe to call before proxying through it.

## Known failure modes

- Empty or vague query returns no matches or low-confidence results
- Endpoint URL not found in the 500+ server index returns a not-found signal
- Prompt injection attempts blocked by Prompt-Guard firewall with an error response
- Payment not processed (x402) results in 402 HTTP response blocking the call
- Network timeout if upstream MCP servers are slow to respond during routing

## 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/mcp-gateway)

## Output

Returns a list of matched MCP servers and A2A tools relevant to the capability query, including endpoint URLs, descriptions, and token-compressed metadata. When given an endpoint URL to verify, confirms whether it is indexed and safe to proxy through the swarm router.

## 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-73f8ff5f/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)