# 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 and routes across 500+ indexed MCP servers and A2A tools with token compression and prompt-injection firewall protection

## Facts

- Endpoint: POST https://x402-audit.agentdiet.dev/v1/workflows/execute?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-2d4e1d4c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_E20BnNq_Ce1fdOXrSdAaO

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-2d4e1d4c -d '<json body>'
```

Example prompt: Search your MCP and A2A tool index for anything that can handle GitHub security audits — I need to find and route to the right tool without blowing my token budget.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which MCP server or A2A tool to invoke for a given task, rather than hardcoding tool URLs. Especially useful in multi-agent swarm architectures where the right downstream tool is unknown at design time. Prefer over direct tool calls when you want built-in prompt-injection firewall screening and token-compressed responses.

## Known failure modes

- Empty query string returns validation error
- No matching tools found for niche capability query returns empty results
- Prompt-Guard firewall may block queries containing injection-like patterns
- Upstream MCP server unavailability may cause partial result sets
- Malformed endpoint URL in query yields verification failure

## 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/workflows/execute)

## Output

Returns a list of matching MCP servers or A2A tools relevant to the query, with tool metadata, routing information, and any Prompt-Guard firewall flags. Results are token-compressed by up to 85% to minimize context usage.

## 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-2d4e1d4c/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)