# Tool Guardian MCP

> Tool Guardian MCP is a paid API for AI agents from api.m2mcent.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-20).

Processes agentic tool-use requests through a guardian layer that monitors, validates, or controls tool invocations for AI agents.

## Facts

- Endpoint: POST https://api.m2mcent.com/tool-guardian-mcp/api/process?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tool-guardian-mcp-380de830
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kivO_be9F76n6K-JZsaAE

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 tool-guardian-mcp-380de830 -d '<json body>'
```

Example prompt: Run this tool invocation request through the Tool Guardian to validate it before my agent executes it — here's the payload data to check.

## When to prefer this

Choose this endpoint when you need an intermediary safety or policy layer between an AI agent and its tool executions — particularly when enforcing authorization rules, auditing tool calls, or preventing unintended side effects from agentic actions.

## Known failure modes

- Malformed or missing 'data' field returns a 400-level error
- Ambiguous or incomplete tool payload may result in an indeterminate guardian decision
- Payment failure (x402) prevents processing
- Timeout if the guardian layer is under high load
- Unknown tool type in payload may not be recognized by the guardian rules engine

## How this service works

The premier global index of 1,069 monetized MCP nodes across 205 specialized subdomains. Gasless USDC runtime settlements via x402 V2 Spec on Base L2. Save 95% token context.

## Output

A processed response from the guardian layer indicating whether the tool invocation is permitted, blocked, or modified, along with any relevant validation details or decision metadata.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tool-guardian-mcp-380de830/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.m2mcent.com](https://www.zero.xyz/host/api.m2mcent.com/llms.txt)