@powforge/captcha-mcp
Charge AI agents per-call without accounts. PoW solve = free tier. Lightning payment = paid tier.
OpenAI's Sora API does not let you charge per call. Anthropic's billing does not pass through to your tools. If you ship an MCP server today and an autonomous agent finds it, you eat the bill.
This is the gate. Three tools over stdio or HTTP. Stdlib only.
Quickstart
npx -y @powforge/captcha-mcpThat is it. No install, no config, no API key. The server starts on stdio and waits for an MCP client.
To wire it into Claude Code, Cursor, or any MCP-compatible host, add to your config:
{
"mcpServers": {
"powforge-captcha": {
"command": "npx",
"args": ["-y", "@powforge/captcha-mcp"]
}
}
}Or run npx @powforge/captcha-mcp --install to print the config block.
What it does
Wraps the PowForge pow-captcha service (captcha.powforge.dev) as three MCP tools:
| Tool | Purpose |
|---|---|
challenge |
Request a fresh proof-of-work puzzle. Returns {id, salt, difficulty, signature}. |
verify |
Submit a solved nonce. Returns a 5-minute HMAC-signed access token. |
status |
Server health, lifetime stats, L402 endpoint metadata. |
