# Proof-of-Work CAPTCHA MCP

> Proof-of-Work CAPTCHA MCP is a paid API for AI agents from api.m2mcent.com, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-12).

Processes proof-of-work CAPTCHA challenges to verify computational effort and grant access or attestation to automated agents

## Facts

- Endpoint: POST https://api.m2mcent.com/proof-of-work-captcha-mcp/api/process?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/proof-of-work-captcha-mcp-71855808
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_LSMyOnr9HBd9uElFIr_k7

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 proof-of-work-captcha-mcp-71855808 -d '<json body>'
```

Example prompt: I need to pass a proof-of-work CAPTCHA gate — here's the challenge data string: 'abc123challenge=='. Can you process it and give me the verification result?

## When to prefer this

Use this endpoint when an AI agent needs to programmatically pass a proof-of-work CAPTCHA gate as part of an automated workflow, especially when accessing services that require computational challenge-response verification. Prefer this over general CAPTCHA bypass services when the challenge is specifically proof-of-work based rather than image-recognition or audio-based CAPTCHAs.

## Known failure modes

- Invalid or malformed challenge data string returns an error or failed validation status
- Expired CAPTCHA challenge data that is no longer valid
- Incorrect computational answer causing verification failure
- Malformed JSON input or missing 'data' field causing a 400-level error
- Transient server errors returning 5xx responses

## 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 response indicating whether the proof-of-work CAPTCHA challenge was successfully validated, including a pass/fail status and potentially an attestation token or verification proof that can be used to proceed past the access gate.

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/proof-of-work-captcha-mcp-71855808/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)