# 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 queries 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/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-bae06e3a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_r3TZ39W7A-TFwUk5G62vA

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-bae06e3a -d '<json body>'
```

Example prompt: Search the MCP and A2A tool index for anything that handles SEC filings or company enrichment — I need the best available tool routed through the safe proxy.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which MCP server or A2A tool can fulfill an unfamiliar capability at runtime, rather than hardcoding specific tool endpoints. Ideal for swarm architectures where agents must self-select the right downstream tool. Prefer this over direct tool calls when you need prompt-injection safety screening, token budget management across multiple tools, or unified access to 500+ tools through a single connection.

## Known failure modes

- Empty or vague query returns low-relevance tool matches
- Query for an uncovered capability returns no results
- Prompt-Guard firewall may block or flag queries containing injection-like patterns
- Network timeout if multiple downstream MCP servers are polled
- Payment failure (HTTP 402) if x402 USDC payment is not attached or insufficient
- Malformed query (minLength not met) returns validation error

## 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/execute)

## Output

Returns a list of matching MCP servers or A2A tools from the 500+ indexed catalog, including routing information, compressed responses (up to 85% token reduction), and safety-filtered output from the Prompt-Guard firewall. May include tool metadata, endpoint URLs, capability descriptions, and recommended routing paths.

## 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-bae06e3a/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)