by Anthropic Claude API
Access Claude AI models including Claude Sonnet 4.5, Claude Opus 4.5, and Claude Haiku. Chat completions, message batches, token counting, and more.
Install the x402 MCP server to let your AI agent access this data with automatic USDC payments on Base.
Required: You need a SerenDB database to store query results.
Get your connection string from the SerenDB Console under your database settings.
Add to claude_desktop_config.json:
{
"mcpServers": {
"x402": {
"command": "npx",
"args": ["@serendb/x402-mcp-server"],
"env": {
"X402_GATEWAY_URL": "https://x402.serendb.com",
"WALLET_PRIVATE_KEY": "0x...",
"BASE_RPC_URL": "https://mainnet.base.org",
"SERENDB_CONNECTION_STRING": "postgresql://..."
}
}
}
}Replace 0x... with your wallet private key and postgresql://... with your SerenDB connection string.
claude mcp add x402 \ -e X402_GATEWAY_URL=https://x402.serendb.com \ -e WALLET_PRIVATE_KEY=0x... \ -e BASE_RPC_URL=https://mainnet.base.org \ -e "SERENDB_CONNECTION_STRING=postgresql://..." \ -- npx -y @serendb/x402-mcp-server
claude mcp add x402 ` -e X402_GATEWAY_URL=https://x402.serendb.com ` -e WALLET_PRIVATE_KEY=0x... ` -e BASE_RPC_URL=https://mainnet.base.org ` -e "SERENDB_CONNECTION_STRING=postgresql://..." ` '--' npx -y @serendb/x402-mcp-server
Replace 0x... with your wallet private key and postgresql://... with your SerenDB connection string.
gemini mcp add x402 \ -e X402_GATEWAY_URL=https://x402.serendb.com \ -e WALLET_PRIVATE_KEY=0x... \ -e BASE_RPC_URL=https://mainnet.base.org \ -e "SERENDB_CONNECTION_STRING=postgresql://..." \ -- npx -y @serendb/x402-mcp-server
Replace 0x... with your wallet private key and postgresql://... with your SerenDB connection string.
codex mcp add x402 \ --env X402_GATEWAY_URL=https://x402.serendb.com \ --env WALLET_PRIVATE_KEY=0x... \ --env BASE_RPC_URL=https://mainnet.base.org \ --env "SERENDB_CONNECTION_STRING=postgresql://..." \ -- npx -y @serendb/x402-mcp-server
Important: Cursor has a 60s timeout. Pre-install globally first: npm install -g @serendb/x402-mcp-server
First, install globally to avoid timeout issues:
npm install -g @serendb/x402-mcp-server
Then add to ~/.cursor/mcp.json:
{
"mcpServers": {
"x402": {
"command": "x402-mcp-server",
"args": [],
"env": {
"X402_GATEWAY_URL": "https://x402.serendb.com",
"WALLET_PRIVATE_KEY": "0x...",
"BASE_RPC_URL": "https://mainnet.base.org",
"SERENDB_CONNECTION_STRING": "postgresql://..."
}
}
}
}Also works with Windsurf, Zed, and other MCP-compatible clients. See the full setup guide for details.
Access data directly via HTTP using the x402 payment protocol.
HTTP 402 with payment requirements (amount, wallet, EIP-712 data)X-PAYMENT header containing the signaturecurl -X POST https://x402.serendb.com/api/proxy \
-H "Content-Type: application/json" \
-d '{
"publisherId": "d94e8d25-1561-46f7-88d1-9ee9a28e0e2a",
"agentWallet": "0xYourWalletAddress",
"request": {
"method": "GET",
"path": "/endpoint"
}
}'This returns 402 Payment Required with the payment details you need to sign.
After signing the EIP-712 authorization, add the base64-encoded signature:
curl -X POST https://x402.serendb.com/api/proxy \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <base64-encoded-signature>" \
-d '{ ... }'Pay per API call via x402 protocol
by Firecrawl
AI-powered web scraping API that turns websites into LLM-ready markdown or structured data. Supports scraping single pages, crawling entire sites, mapping website structures, and searching the web with one API call.
by Perplexity
Perplexity is an AI-powered search engine that provides accurate, up-to-date answers with citations. Access raw web search results or grounded LLM responses through Sonar models.
by Moonshot AI
Moonshot AI Kimi K2 - trillion-parameter MoE model with 256K context. State-of-the-art performance in coding, math, and reasoning. OpenAI-compatible API.