# 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 prompt-guard.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 via a single connection, with prompt-injection firewall and token compression

## Facts

- Endpoint: GET https://prompt-guard.agentdiet.dev/v1/workflows?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: prompt-guard.agentdiet.dev
- Website: https://prompt-guard.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/prompt-guard-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-bcdfb4b9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CtuCpkdwYvSTc12bP0Dos

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 prompt-guard-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-bcdfb4b9
```

Example prompt: Search for MCP tools that handle SEC filings retrieval and give me the best matching endpoints I can connect to.

## When to prefer this

Choose this endpoint when an agent needs to dynamically discover which MCP servers or A2A tools are available for a given capability without maintaining its own tool registry. Especially useful when building multi-agent swarms that need safe, compressed, single-connection access to a broad catalog of 500+ tools, or when you need prompt-injection protection at the routing layer.

## Known failure modes

- Empty results if query is too narrow or uses non-standard terminology
- Firewall may block or flag queries that resemble prompt injection attempts
- Indexed tool may be stale or offline at routing time
- Ambiguous queries may return low-relevance results across unrelated tool categories
- Payment failure via x402 may prevent request from being processed

## 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://prompt-guard.agentdiet.dev/v1/workflows)

## Output

A list of matching MCP servers and A2A tool endpoints relevant to the query, including tool metadata, endpoint URLs, and routing information, filtered through the Prompt-Guard firewall with compressed context to minimize token usage.

## 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/prompt-guard-agentdiet-dev-universal-a2a-mcp-tool-discovery-safe-bcdfb4b9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from prompt-guard.agentdiet.dev](https://www.zero.xyz/host/prompt-guard.agentdiet.dev/llms.txt)