# 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 x402-audit.agentdiet.dev, paid per call via MPP, $0.01/call, status unknown (last checked 2026-10-23).

Searches a meta-index of 500+ MCP servers and A2A tools by capability query, routing through a Prompt-Guard firewall with 85% token compression

## Facts

- Endpoint: POST https://x402-audit.agentdiet.dev/v1/security-audit-dag?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Provider: x402-audit.agentdiet.dev
- Website: https://x402-audit.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/x402-audit-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-9953d4b7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UwjV_2_6Bdg2gbOj__Tyo

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 x402-audit-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-9953d4b7 -d '<json body>'
```

Example prompt: Search the MCP and A2A tool index for servers that can handle 'company enrichment' — I want to find available tools and route through the safe proxy.

## When to prefer this

Use this endpoint when an agent needs to dynamically discover which MCP servers or A2A tools are available for a given capability without maintaining its own registry, especially when prompt injection safety and token efficiency are concerns. Prefer over manual tool registries when working with swarm architectures or when you need a single connection point to hundreds of tools.

## Known failure modes

- Empty query string returns validation error
- No matching tools found for obscure capability query returns empty results
- Endpoint URL verification fails if the target is offline
- Rate limiting or payment failure if x402 payment is not processed
- Prompt-Guard may block or redact results flagged as injection attempts

## 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://x402-audit.agentdiet.dev/v1/security-audit-dag)

## Output

Returns a filtered, token-compressed list of matching MCP servers and A2A tools from a 500+ item index, including tool metadata and routing information, with prompt-injection filtered out by the Prompt-Guard firewall.

## 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/x402-audit-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-9953d4b7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-audit.agentdiet.dev](https://www.zero.xyz/host/x402-audit.agentdiet.dev/llms.txt)