ToolFi — API Marketplace for AI Agents

"The next unicorn is an API marketplace for agents... where the right API should be selected by Claude and connected automatically" — @auralix4

API marketplaces exist, but they're built for human developers. ToolFi is built for AI workflows — agents discover, select, and pay for APIs automatically, without human intervention.

🌐 Website · 📡 API · 📜 Contract · 🗺️ Roadmap

The Problem

AI agents need external data (prices, security checks, routes). Current solutions:

RapidAPI, etc. — Built for humans. Agents can't browse and click "Subscribe"
Hardcoded keys — Security risk, doesn't scale
Manual integration — Every new tool needs human setup

The Solution

ToolFi = APIs that agents can discover and use autonomously.

Discovery — Agents find tools via .well-known/mcp.json, MCP registries, semantic search
Selection — Rich descriptions help agents pick the right tool
Payment — USDC on Base, no API keys, just pay and use
Data — Structured responses optimized for LLM consumption

How It Works

Agent → GET /api/price?symbol=ETH
                ↓
Server → 402 Payment Required
         { toolId, price, paymentInstructions }
                ↓
Agent → USDC.approve() → Registry.payForCall(toolId)
                ↓
Agent → Retry with X-Payment-Tx header
                ↓
Server → Verify on-chain → Return data

Available Tools

Tool	Price	What it does
Crypto Price Oracle	0.001 USDC	Real-time prices via DexScreener
Rug Pull Scanner	0.003 USDC	Token security via GoPlus
Bridge Router	0.002 USDC	Cross-chain routes via Li.Fi
DeFi Yield Finder	0.002 USDC	Best yields via DefiLlama
Swap Router	0.002 USDC	DEX aggregation via Li.Fi
Trending Coins	0.001 USDC	What's hot via CoinGecko
Protocol TVL	0.001 USDC	DeFi TVL data via DefiLlama
Gas Tracker	0.0005 USDC	Gas prices for EVM chains
Wallet Risk Scanner	0.005 USDC	Address risk analysis
News Digest	0.002 USDC	Crypto news summary

Integration Options

Option 1: HTTP API (Any Agent)

# Pay on-chain, then call with payment proof
curl -H "X-Payment-Tx: 0x..." "https://toolfi.vercel.app/api/price?symbol=ETH"

Option 2: MCP Server (Claude Desktop)

cd mcp-server
uv venv && source .venv/bin/activate
uv pip install -e .

Add to Claude Desktop config:

{
  "mcpServers": {
    "toolfi": {
      "command": "/path/to/.venv/bin/python",
      "args": ["-m", "src.server"],
      "cwd": "/path/to/mcp-server"
    }
  }
}

Then ask Claude: "Check the security of token 0x... on Base"

For Tool Creators

Publish your API and earn USDC:

cast send $REGISTRY \
  "registerTool(string,string,string,uint256)" \
  "My Tool" "https://api.example.com" "Description" 10000 \
  --rpc-url https://sepolia.base.org --private-key $KEY

Price in 6 decimals: 10000 = $0.01/call

Withdraw earnings:

cast send $REGISTRY "withdraw()" --rpc-url https://sepolia.base.org

Contract


Chain	Base Sepolia (84532)
USDC	`0x036CbD53842c5426634e7929541eC2318f3dCF7e`
Registry	`0x3D6C600799C67b45061eCAbfD5bBF8ef57Dded88`

Project Structure

toolfi/
├── api/           # Vercel serverless API
├── web/           # Next.js frontend
├── mcp-server/    # Python MCP server for Claude
├── src/           # Solidity contracts
├── skill/         # OpenClaw skill spec
└── script/        # Deployment scripts

Development

# Contracts
forge build
forge test -v

# API
cd api && npm install && npm start

# MCP Server
cd mcp-server && uv pip install -e . && python -m src.server

Roadmap

License

MIT

toolfi