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

Searches an index of 500+ MCP servers and A2A tools by capability query, returning compressed, firewall-screened tool metadata via a single connection

## Facts

- Endpoint: GET https://defi-yield.agentdiet.dev/v1/execute?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: defi-yield.agentdiet.dev
- Website: https://defi-yield.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/defi-yield-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-a785861e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zlh9RDpIsQRIf9aQyK_ku

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 defi-yield-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-a785861e
```

Example prompt: Search the MCP and A2A tool index for anything that can do 'SEC filings' or 'company enrichment' — I want to see which servers are available and get their compressed schema so I can pick one to call.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover which MCP servers or A2A tools are available for a given capability rather than hardcoding tool URLs. It is especially useful for multi-agent swarm orchestration, building tool registries, or when you need token-efficient compressed schemas and Prompt-Guard safety filtering in a single call.

## Known failure modes

- Empty query string returns validation error
- No matching tools found for niche query returns empty result set
- Endpoint URL verification may fail if target is offline
- Overly broad queries may return too many results to be actionable
- Rate limiting or payment failure (HTTP 402) if $0.01 per-call credit is not available

## 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://defi-yield.agentdiet.dev/v1/execute)

## Output

Returns a structured list of matching MCP servers and A2A tools from a 500+ entry index, with compressed tool schemas (85% token reduction), safety-filtered through a Prompt-Guard firewall, including routing metadata and capability descriptors.

## 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/defi-yield-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-proxy-a785861e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from defi-yield.agentdiet.dev](https://www.zero.xyz/host/defi-yield.agentdiet.dev/llms.txt)