# Universal A2A & MCP Tool Discovery, Safe-Proxy & Swarm Router (RAG Context Sanitizer)

> Universal A2A & MCP Tool Discovery, Safe-Proxy & Swarm Router (RAG Context Sanitizer) is a paid API for AI agents from serp-extract.agentdiet.dev, paid per call via MPP, $0.005/call, status unknown (last checked 2026-10-21).

Searches an index of 500+ MCP servers and A2A tools by capability query, returning compressed, prompt-safe tool discovery results with built-in firewall filtering.

## Facts

- Endpoint: GET https://serp-extract.agentdiet.dev/v1/workflows/rag-context-sanitizer?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- 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-0870ac9a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_T7ekReiqnn-qheutoGUQ4

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-0870ac9a
```

Example prompt: Search the MCP and A2A tool index for any servers that handle 'SEC filings' — I need to find a safe, compressed-context tool I can route my agent to.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which MCP servers or A2A tools exist for a given capability, especially when operating in a multi-agent swarm context that benefits from token-compressed, firewall-filtered tool metadata rather than manually curating a tool list.

## Known failure modes

- Empty query string returns validation error
- No matching tools found returns empty result set
- Endpoint URL verification may fail if target is unreachable
- Prompt-guard firewall may strip or redact query content deemed unsafe
- Rate limiting or payment required (HTTP 402) if call quota exceeded

## How this service works

Scans untrusted web pages, emails, MCP responses, or A2A payloads for hidden prompt injections and returns sanitized text. (Live x402 v2, IETF MPP & MCP endpoint at https://serp-extract.agentdiet.dev/v1/workflows/rag-context-sanitizer)

## Output

Returns a filtered, token-compressed list of matching MCP servers and A2A tools from a 500+ entry index, with prompt-guard sanitization applied. Results include tool metadata, capability summaries, and relevant endpoint URLs.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "text"
 ],
 "properties": {
  "text": {
   "type": "string",
   "minLength": 1,
   "description": "Untrusted text, HTML, or tool output to scan for hidden prompt injection or jailbreak payloads"
  },
  "limit": {
   "type": "integer",
   "default": 20,
   "maximum": 100,
   "minimum": 1,
   "description": "Maximum number of items to return per page (1-100)"
  },
  "cursor": {
   "type": "string",
   "description": "Opaque pagination cursor for fetching the next page"
  }
 }
}
```

## 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-0870ac9a/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)