# Services from x402.freeq.one on Zero > x402.freeq.one serves 24 paid API services for AI agents, indexed by Zero. Each is callable per call with payment handled by Zero. Canonical page: https://www.zero.xyz/host/x402.freeq.one Live health (JSON, refreshed every minute): https://www.zero.xyz/host/x402.freeq.one/health.json ## Services - [x402-gateway: wallet_verify_solana](https://www.zero.xyz/c/x402-gateway-wallet-verify-solana-b6b5b967/llms.txt): $0.002/call via x402. Verify an ed25519 Solana wallet signature over a nonce-containing message and return the signer's public key, consuming the nonce on success. - [x402-gateway: wallet_verify_siwe](https://www.zero.xyz/c/x402-gateway-wallet-verify-siwe-0276ee47/llms.txt): $0.002/call via x402. Verify a Sign-In-With-Ethereum (EIP-4361) SIWE signature, returning the recovered wallet address and chainId without creating sessions or consuming nonces. - [x402-gateway Mermaid Diagram Renderer](https://www.zero.xyz/c/x402-gateway-mermaid-diagram-renderer-d87495ce/llms.txt): $0.005/call via x402. Renders a Mermaid diagram definition string into a PNG or SVG image, returning a base64-encoded image via MCP content type. - [x402-gateway: verify_batch (Semaphore ZK Proof Batch Verifier)](https://www.zero.xyz/c/x402-gateway-verify-batch-semaphore-zk-proof-batch-verifier-5a0e0093/llms.txt): $0.005/call via x402. Batch-verifies up to 10 Semaphore ZK proofs in a single pay-per-call request, returning per-proof results with total count and average verification duration. - [x402-giftcard-api](https://www.zero.xyz/c/x402-giftcard-api-bb56191e/llms.txt): $0.05/call via x402. Purchase a digital gift card code for a specified product and face value, paid via x402 micropayment protocol. - [x402-gateway: wallet_checksum](https://www.zero.xyz/c/x402-gateway-wallet-checksum-e1089349/llms.txt): $0.002/call via x402. Converts an Ethereum address to its EIP-55 checksummed form for use in SIWE (Sign-In With Ethereum) messages and other standards requiring checksummed addresses. - [x402-gateway: verify_semaphore](https://www.zero.xyz/c/x402-gateway-verify-semaphore-8d21ad7b/llms.txt): $0.002/call via x402. Locally verify a Semaphore ZK proof using Groth16 with an embedded official verification key, requiring no external dependencies. - [x402-gateway: wallet_verify_nostr](https://www.zero.xyz/c/x402-gateway-wallet-verify-nostr-d49780f9/llms.txt): $0.002/call via x402. Verifies a NIP-98 Nostr HTTP authentication event and returns the signer's public key, with stateful replay protection ensuring each event ID is only accepted once. - [x402.freeq.one LLM Chat](https://www.zero.xyz/c/x402-freeq-one-llm-chat-94a1e5b0/llms.txt): $0.002/call via x402. Chat with a language model via an OpenAI-compatible /v1/chat/completions interface supporting 50+ models, paid per-call in USDC on Base via x402 - [x402-gateway: verify_worldid](https://www.zero.xyz/c/x402-gateway-verify-worldid-4f4eb890/llms.txt): $0.005/call via x402. Verifies a World ID 4.0 proof by proxying through the Worldcoin Developer Portal API with server-side RP signature generation, returning validity, nullifier, and raw Worldcoin response. - [x402-gateway QR Code & Barcode Generator](https://www.zero.xyz/c/x402-gateway-qr-code-barcode-generator-99c08c51/llms.txt): $0.002/call via x402. Generates a QR code or barcode image (SVG or PNG) for a given data string and symbology, returning a base64-encoded image via a pay-per-call API. - [x402-gateway HTML to Markdown Converter](https://www.zero.xyz/c/x402-gateway-html-to-markdown-converter-f3bbd1d4/llms.txt): $0.002/call via x402. Converts an HTML string to clean, LLM-ready Markdown with configurable heading style, bullet markers, code block style, and emphasis delimiters. - [x402-gateway Gift Card Purchase API](https://www.zero.xyz/c/x402-gateway-gift-card-purchase-api-5dad286b/llms.txt): $0.05/call via x402. Buy a digital gift card by product ID and face value, settled in USDC on Base via the x402 pay-per-call protocol — no account required. - [x402-gateway — Pay-per-call MCP on Base via Coinbase CDP x402](https://www.zero.xyz/c/x402-gateway-pay-per-call-mcp-on-base-via-coinbase-cdp-x402-f98eb185/llms.txt): $0.001/call via x402. A pay-per-use MCP gateway exposing 15 tools (including markdown, token prices, wallet portfolio, whale alerts, and more) over the x402 payment protocol on Base, requiring no accounts, logins, or API keys. - [x402-gateway OG Image Generator](https://www.zero.xyz/c/x402-gateway-og-image-generator-aa795509/llms.txt): $0.002/call via x402. Generates a 1200x630 Open Graph social-card PNG image from a title and description, returned as a base64-encoded image. - [x402-gateway MCP Multi-Tool Gateway](https://www.zero.xyz/c/x402-gateway-mcp-multi-tool-gateway-a2fc7e57/llms.txt): $0.001/call via x402. Pay-per-call MCP gateway exposing 7 tools (markdown conversion, token price, wallet portfolio, whale alerts, cross-chain balance, changelog from OpenAPI, changelog from Git) with per-tool micropayments on Base via x402 - [x402-gateway Whale Alerts](https://www.zero.xyz/c/x402-gateway-whale-alerts-94036441/llms.txt): $0.002/call via x402. Fetches large on-chain cryptocurrency transfer alerts (whale movements) across blockchain networks, paid per-call via x402 on Base. - [x402-gateway Token Price Lookup](https://www.zero.xyz/c/x402-gateway-token-price-lookup-bdff11cf/llms.txt): $0.002/call via x402. Returns the current price of a cryptocurrency token, paid per-call via x402 micropayment on Base. - [x402-gateway changelog_git](https://www.zero.xyz/c/x402-gateway-changelog-git-5465ddbd/llms.txt): $0.005/call via x402. Generate a formatted changelog from a Git repository's commit history using AI, paying per call via x402 micropayments on Base - [x402-gateway: cross_chain_balance](https://www.zero.xyz/c/x402-gateway-cross-chain-balance-6f28fa20/llms.txt): $0.002/call via x402. Fetches the token balances of a wallet address across multiple blockchain networks in a single call - [x402-gateway changelog_openapi](https://www.zero.xyz/c/x402-gateway-changelog-openapi-9ce9fd9e/llms.txt): $0.005/call via x402. Generates a structured changelog from an OpenAPI specification, diffing versions to surface added, changed, or removed endpoints and schemas - [x402-gateway Markdown Renderer](https://www.zero.xyz/c/x402-gateway-markdown-renderer-def248ac/llms.txt): $0.002/call via x402. Converts a Markdown string to rendered HTML via a pay-per-call x402 micropayment gateway on Base - [x402-gateway Wallet Portfolio Tool](https://www.zero.xyz/c/x402-gateway-wallet-portfolio-tool-a12457e8/llms.txt): $0.002/call via x402. Returns the token holdings and balances across a wallet address on Base and other chains, paid per-call via x402 micropayment. - [x402-gateway Jobs Tool](https://www.zero.xyz/c/x402-gateway-jobs-tool-8adde3a4/llms.txt): $0.002/call via x402. Fetches job listings via a pay-per-call MCP gateway secured by x402 micropayments on Base Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. - [Zero catalog index](https://www.zero.xyz/llms.txt)