Fabler x402 Tools — Claude Code MCP server: tools & setup
Connects AI agents to utility APIs with micro-payments via the x402 protocol on Base. Useful for secret scanning, config auditing, and fetching market funding rates.
claude mcp add --transport http x402-tools https://x402.fablerlabs.com/mcpWhat Fabler x402 Tools does
This server connects coding agents to pay-per-call utilities settled on Base via the x402 protocol. Its toolset includes secret scanning for tokens such as GitHub or Stripe keys, structural scoring of CLAUDE.md files from 0 to 100, and validation of 18-point pre-deploy records. It also provides public URL header analysis, clean article text extraction, 1200×630 social image generation, and funding rate spreads across derivative exchanges.
No user account or API key is required. Instead, on-chain USDC payment acts as authentication. Pricing for most endpoints is resolved dynamically at runtime through a free catalog tool, while crypto funding data has a fixed fee of $0.001.
Automating payments requires setting X402_BUYER_PRIVATE_KEY in your environment. Storing a private key from an active primary wallet creates unnecessary risk, so using an isolated account with pocket-change funding is safer. Omission of this key leaves the server in inspect mode, returning an HTTP 402 challenge response on paid requests.
What it helps with
- scan code repositories for leaked API tokens and secrets
- evaluate agent instruction files like
CLAUDE.mdorAGENTS.md - inspect public web endpoints for HTTPS redirects and security headers
- retrieve normalized perpetual futures funding spreads across exchanges
- generate social preview images for web assets
Example prompts for the agent
- Inspect
.env.exampleusingfabler_scan_secretsto identify leaked credentials - Run
fabler_audit_agent_configonCLAUDE.mdto grade our project instructions - Fetch current perpetual futures funding spreads using
fabler_market_funding_spreads
How to install Fabler x402 Tools
Platform CLI: remote server
claude mcp add --transport http x402-tools https://x402.fablerlabs.com/mcpPlatform CLI: remote server
codex mcp add fabler-x402-tools --url https://x402.fablerlabs.com/mcpConfig file
{
"mcpServers": {
"fabler-x402-tools": {
"url": "https://x402.fablerlabs.com/mcp"
}
}
}Config file
{
"servers": {
"fabler-x402-tools": {
"type": "http",
"url": "https://x402.fablerlabs.com/mcp"
}
}
}Platform CLI: remote server
gemini mcp add -t http fabler-x402-tools https://x402.fablerlabs.com/mcpStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Fabler x402 Tools
How to install Fabler x402 Tools in Claude Code?
Run claude mcp add --transport http x402-tools https://x402.fablerlabs.com/mcp in your terminal. This immediately connects the remote catalog and preview endpoints.
What does Fabler x402 Tools do?
It gives AI assistants on-demand access to specialized tools funded per call on Base. Capabilities include secret detection, agent config audits, URL security checks, and crypto market spreads.
Do you need a private key to use the server?
No, providing a key is optional. Without X402_BUYER_PRIVATE_KEY, tools execute in inspect mode and return an HTTP 402 payment challenge without moving any funds.
