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

Searches and discovers MCP servers and A2A tools from a 500+ item index via a single meta-router connection with built-in prompt-injection firewall and 85% token compression

## Facts

- Endpoint: GET https://onchain-risk.agentdiet.dev/v1/mcp-gateway?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Provider: onchain-risk.agentdiet.dev
- Website: https://onchain-risk.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/onchain-risk-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-2cdc4968
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_C9vl-QkgFoOXypEV3PHYa

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 onchain-risk-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-2cdc4968
```

Example prompt: Search the MCP and A2A tool index for capabilities related to 'SEC filings' and return the top 10 results so I can pick the best server to route that task through.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which MCP server or A2A tool to use for a given capability, rather than hardcoding a specific tool. It is ideal for swarm orchestration, meta-routing across 500+ tools, or when you need a safe-proxied, token-efficient single connection that includes prompt-injection protection across all routed calls.

## Known failure modes

- Empty results if query matches no indexed capabilities
- Rate limiting or 402 payment required if x402 micropayment not provided
- Invalid cursor returns pagination error
- Query too short (minLength:1 violated) returns validation error
- Upstream MCP server unavailability may reduce index freshness

## 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://onchain-risk.agentdiet.dev/v1/mcp-gateway)

## Output

A paginated list of matching MCP servers and A2A tools from the 500+ item index, including endpoint metadata, capability descriptions, and routing details. Results are token-compressed (85% reduction) and have passed through the Prompt-Guard firewall to filter malicious payloads.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "query"
 ],
 "properties": {
  "limit": {
   "type": "integer",
   "default": 20,
   "maximum": 100,
   "minimum": 1,
   "description": "Maximum number of items to return per page (1-100)"
  },
  "query": {
   "type": "string",
   "minLength": 1,
   "description": "Capability search query (e.g. 'context compression', 'github security', 'sec filings', 'company enrichment') or endpoint URL to verify"
  },
  "cursor": {
   "type": "string",
   "description": "Opaque pagination cursor for fetching the next page"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/onchain-risk-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-2cdc4968/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from onchain-risk.agentdiet.dev](https://www.zero.xyz/host/onchain-risk.agentdiet.dev/llms.txt)