# 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 2026-10-21).

Searches and routes queries across 500+ indexed MCP servers and A2A tools through a single connection with token compression and prompt safety filtering.

## Facts

- Endpoint: GET https://onchain-risk.agentdiet.dev/v1/tool-broker?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- 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-b43f5ca5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_0Ed5fTpHJ4zL0H3deSCzi

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-b43f5ca5
```

Example prompt: Search the MCP tool broker for any indexed servers that handle SEC filings or company enrichment — I need a single-connection discovery query to find what's available.

## When to prefer this

Choose this endpoint when an AI agent needs to dynamically discover and route to external MCP servers or A2A tools without maintaining its own index. Ideal for agentic swarm architectures, tool orchestration layers, or when token budget is a concern and 85% compression is valuable. Prefer this over manual tool registration when the target capability is unknown or when safety-filtering of tool outputs is required.

## Known failure modes

- Empty or vague query returns no matches or low-confidence results
- Queried capability not indexed in the current catalog returns empty result set
- Endpoint URL verification for an unknown URL returns unverified status
- Rate limiting or payment failure (HTTP 402) blocks the request
- Prompt-Guard firewall may block queries flagged as unsafe or adversarial

## 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/tool-broker)

## Output

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

## 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/onchain-risk-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-b43f5ca5/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)