# 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 across 500+ MCP servers and A2A tools via a single meta-router endpoint with 85% token compression and a Prompt-Guard firewall.

## Facts

- Endpoint: POST https://serp-extract.agentdiet.dev/v1/a2a-mesh?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-27b2f373
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_vl6vLccKK5zx8Q-nK1Dop

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-27b2f373 -d '<json body>'
```

Example prompt: Search the A2A mesh for MCP tools that handle SEC filings and company enrichment — I need to route my agent to the right endpoint without wasting tokens.

## When to prefer this

Choose this endpoint when you need a single connection to discover, evaluate, or route across a large indexed corpus of MCP servers and A2A tools — especially when token efficiency matters or when you need firewall-protected proxying. Prefer alternatives when you need to call a specific known tool directly rather than discovering or routing to one.

## Known failure modes

- Empty or vague query returns low-relevance or no results
- Endpoint URL verification may fail if the target is offline or unreachable
- Token compression may lose nuance in tool descriptions for edge-case queries
- Prompt-Guard firewall may block queries containing injection-like patterns
- Payment required (HTTP 402) if x402 credentials are not provided or are invalid

## 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/a2a-mesh)

## Output

Returns a list of matching MCP servers or A2A tools relevant to the query, with token-compressed metadata and Prompt-Guard firewall filtering applied. May include endpoint URLs, capability descriptions, and safety signals for each matched tool.

## 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-27b2f373/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)