# 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 500+ indexed MCP servers and A2A tools by capability query, returning compressed, firewall-filtered results for agent tool discovery and routing.

## Facts

- Endpoint: POST https://serp-extract.agentdiet.dev/api/mcp/audit?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-21eef77a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_PWqZBNijbwCUJ9SSK_-Kc

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-21eef77a -d '<json body>'
```

Example prompt: Search the MCP and A2A tool index for servers that support context compression — I want to find available tools I can route through for shrinking token usage in my agent pipeline.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover, search, or route to MCP servers or A2A tools by capability at runtime, especially when token budget is constrained (85% compression) or when you need firewall-protected tool discovery across a broad index of 500+ servers in a single call. Prefer this over manual MCP server lists or static tool registries.

## Known failure modes

- Empty query string returns validation error
- No matching tools found for niche capability returns empty result set
- Endpoint URL verification query fails if the target URL is unreachable
- Rate limiting or payment failure ($0.01/call) blocks access
- Prompt-Guard firewall may block or sanitize adversarial query inputs
- Ambiguous queries may return loosely relevant or low-confidence 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://serp-extract.agentdiet.dev/api/mcp/audit)

## Output

Returns a compressed, firewall-screened list of matching MCP servers or A2A tools relevant to the capability query, including tool metadata, endpoint URLs, compliance indicators, and routing suggestions — with up to 85% token reduction compared to raw listings.

## 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-21eef77a/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)