# 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 and routes across 500+ indexed MCP servers and A2A tools via a single connection, with prompt-injection firewall and 85% token compression

## Facts

- Endpoint: GET https://defi-yield.agentdiet.dev/v1/a2a-router?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-a18894df
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yIQSdAQhkvPn6W01Qu9hW

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-a18894df
```

Example prompt: Search the MCP and A2A tool index for anything that can do GitHub security auditing — I want to find which tools are available and route my request to the right one.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which MCP server or A2A tool can fulfill a capability requirement without hardcoding specific endpoints. Ideal for meta-agent architectures, swarm orchestration, or when building agents that need to self-route across a broad ecosystem of 500+ tools. Prefer this over direct tool calls when the right downstream tool is unknown at design time.

## Known failure modes

- Empty or vague query returns low-relevance results
- Unknown or unsupported capability category yields no matches
- Endpoint URL verification for an unindexed server returns not-found
- Payment failure (x402) blocks access
- Tool index may lag behind newly added MCP servers

## 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/a2a-router)

## Output

Returns a ranked list of matching MCP servers and A2A tools relevant to the search query, including metadata about each tool's capabilities, endpoint URLs, and routing information — delivered with 85% token compression to minimize context overhead.

## 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-a18894df/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)