x402engine-mcp
MCP server for x402 Engine — giving AI agents access to 38 pay-per-call APIs via HTTP 402 micropayments.
Payments are made with USDC on Base, USDC on Solana, or USDm on MegaETH. Prices range from $0.001 to $0.12 per call.
Quick Start
Claude Desktop
Add to your claude_desktop_config.json:
{
"mcpServers": {
"x402engine": {
"command": "npx",
"args": ["-y", "x402engine-mcp"],
"env": {
"X402_DEV_BYPASS": "your-dev-bypass-secret"
}
}
}
}
Claude Code
claude mcp add x402engine -- npx -y x402engine-mcp
LLM Inference
| Tool | Price | Description |
|---|
llm_chat | $0.002-$0.09 | Chat completion with any supported model |
Supported models: GPT-4o ($0.04), GPT-4o Mini ($0.003), OpenAI o1 ($0.03), Claude Opus 4.6 ($0.09), Claude Sonnet 4.5 ($0.06), Claude Haiku 4.5 ($0.02), Gemini 2.5 Pro ($0.035), Gemini 2.5 Flash ($0.009), Grok 4 ($0.06), DeepSeek V3 ($0.005), DeepSeek R1 ($0.01), Llama 3.3 70B ($0.002), Mistral Large 3 ($0.006), Qwen3 235B ($0.004), Perplexity Sonar Pro ($0.06).
Image Generation
| Tool | Price | Description |
|---|
generate_image | $0.015-$0.12 | AI image generation (fast/quality/text tiers) |
Code Execution
| Tool | Price | Description |
|---|
execute_code | $0.005 | Sandboxed code execution (Python, JS, Bash, R) |
Audio
| Tool | Price | Description |
|---|
transcribe_audio | $0.10 | Audio-to-text transcription (Deepgram Nova-3) |
tts_openai | $0.01 | Text-to-speech (OpenAI) |
tts_elevenlabs | $0.02 | Text-to-speech (ElevenLabs) |
Text Embeddings
| Tool | Price | Description |
|---|
create_embeddings | $0.001 | Text embeddings (OpenAI text-embedding-3-small) |
Crypto & Market Data
| Tool | Price | Description |
|---|
get_crypto_price | $0.001 | Current crypto prices |
get_crypto_markets | $0.002 | Top coins by market cap |
get_crypto_history | $0.003 | Historical price charts |
get_trending_crypto | $0.001 | Trending coins |
search_crypto | $0.001 | Search for coins |
Blockchain & Wallet
| Tool | Price | Description |
|---|
get_wallet_balances | $0.005 | Token balances for any wallet |
get_wallet_transactions | $0.005 | Transaction history |
get_wallet_pnl | $0.01 | Profit & loss analysis |
get_token_prices | $0.005 | DEX-derived token prices |
get_token_metadata | $0.002 | Token metadata |
simulate_transaction | $0.01 | Transaction simulation (Tenderly) |
Web
| Tool | Price | Description |
|---|
web_scrape | $0.005 | Scrape and extract web page content |
web_screenshot | $0.01 | Capture web page screenshot |
IPFS Storage
| Tool | Price | Description |
|---|
pin_to_ipfs | $0.01 | Pin JSON to IPFS |
get_from_ipfs | $0.001 | Retrieve content from IPFS |
Discovery
| Tool | Price | Description |
|---|
discover_services | Free | List all services and pricing |
Environment Variables
| Variable | Required | Description |
|---|
X402_BASE_URL | No | Gateway URL (default: https://x402-gateway-production.up.railway.app) |
X402_DEV_BYPASS | No | Dev bypass secret to skip payments |
X402_PAYMENT_HEADER | No | Pre-signed payment header |
Payment Networks
- Base (EVM) — USDC, 6 decimals, ~2s confirmation
- Solana — USDC, 6 decimals, ~400ms confirmation
- MegaETH (EVM) — USDm, 18 decimals, ~10ms confirmation
How It Works
- Agent calls an MCP tool (e.g.,
llm_chat)
- MCP server makes HTTP request to x402engine.app
- Gateway returns
402 Payment Required with pricing
- Agent pays with crypto via the x402 protocol
- Gateway verifies payment on-chain and returns data
For automatic payment handling, use @x402/fetch in your agent code.
Links
