# 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 mcp-security.agentdiet.dev, paid per call via MPP, $0.01/call, status unknown (last checked 2026-10-21).

Searches and routes across 500+ MCP servers and A2A tools via a single connection, with token compression and prompt-injection firewall.

## Facts

- Endpoint: GET https://mcp-security.agentdiet.dev/v1/web-rag-shield-dag?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: mcp-security.agentdiet.dev
- Website: https://mcp-security.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/mcp-security-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-ce1e9be5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HvzOIIISaDieCkjfeyZlj

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 mcp-security-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-ce1e9be5
```

Example prompt: Search the MCP tool index for capabilities related to 'company enrichment' — I need to find the right A2A server to handle B2B lead data, with prompt-injection protection enabled.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which MCP server or A2A tool to use for a given capability, rather than hardcoding a specific tool endpoint. Ideal for swarm orchestration, meta-routing, and scenarios where the right downstream tool is unknown at design time. Prefer this over direct tool calls when you want built-in prompt-injection firewall protection on discovered tool responses.

## Known failure modes

- Empty query string returns validation error (minLength:1 required)
- Query too vague may return no matching tools or low-confidence results
- Prompt-Guard firewall may block queries that resemble injection patterns
- Underlying MCP server index may be stale if recently added servers haven't been indexed
- Payment not satisfied (HTTP 402) if x402 micropayment of $0.01 USDC is not completed

## 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://mcp-security.agentdiet.dev/v1/web-rag-shield-dag)

## Output

Returns a list of matching MCP servers and A2A tools relevant to the query, including endpoint metadata, capability descriptions, and firewall-validated routing information, with up to 85% token compression applied to the response payload.

## 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/mcp-security-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-ce1e9be5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mcp-security.agentdiet.dev](https://www.zero.xyz/host/mcp-security.agentdiet.dev/llms.txt)