MCP server for AI agents: 31 tools (blockchain data, web scraping, ZK proofs, image generation, gift cards) payable per call in USDC on Base via x402. Send JSON-RPC tools/call requests.

Git Changelog Generator: Diff git commits and generate a structured breaking-change changelog. Provide repository_url, base_commit, and optional target_commit. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/changelog_git.

OpenAPI Changelog Generator: Diff two OpenAPI specs and generate a structured breaking-change changelog (no LLM — deterministic diff). Provide base_spec_url and new_spec. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/changelog_openapi.

Cross-Chain Balance Checker: Aggregate native balance and token/NFT counts for an address across eth, arb, base, polygon, opt. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/cross_chain_balance.

Document to Markdown (auto-detect): Convert any document to Markdown with automatic format detection. One endpoint for pdf, docx, pptx, xlsx, csv, epub, html and plain text — provide a URL or base64 bytes and the type is detected from the file contents. Spreadsheets return both a Markdown table and a JSON array of rows. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/document_to_markdown.

DOCX to Markdown: Convert a DOCX (Word) document to clean, LLM-ready Markdown. Provide a direct URL or base64-encoded file bytes. Preserves headings, lists, tables and formatting. Works for contracts, resumes, reports and letters. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/docx_to_markdown.

EPUB to Markdown: Convert an EPUB e-book to clean Markdown. Provide a direct URL or base64-encoded file bytes. Chapters become headings; metadata (title, author) is included. Feed whole books into LLM context or RAG. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/epub_to_markdown.

Buy a digital gift card and receive the code instantly. Payment settles on Base via x402.

HTML to Markdown Converter: Convert an HTML string to clean, LLM-ready Markdown. Handles headings, links, images, tables, lists and code blocks. Options: heading style (atx|setext), bullet list marker, code block style, emphasis delimiters. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/html_to_markdown.

Job Search: Search live job postings by keywords and locations. Returns structured results: title, company, location, apply URL, work types, employment type, seniority, industry, salary, and description. Supports onsite/remote/hybrid preferences. One call covers the whole market for a keyword + location pair. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/jobs.

LLM Chat: Chat with a language model. OpenAI-compatible /v1/chat/completions interface. Supports 50+ models. Free models (auto, eco, premium) are $0 — paid models (gpt-5.2, claude-opus-5, deepseek-v4-pro, ...) are charged at cost. See /tools/llm_chat/models for the full model list and rates. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/llm_chat.

Markdown Extractor: Fetch a URL and convert its main content to clean, LLM-ready Markdown (strips nav/ads/sidebars). Options: output_format (markdown|text|json), css_selector, max_length, include_links, include_images. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/markdown.

Mermaid Diagram Renderer: Render a Mermaid diagram to an image (PNG or SVG). Returns a base64-encoded image (MCP content type image). Options: format (png|svg), theme (default|dark|forest|neutral), scale (1-4, PNG only). Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/mermaid.

OG Image Generator: Generate an Open Graph social-card image (1200x630 PNG) from a title and description. Returns a base64-encoded image (MCP content type image). Optional image URL embeds a header graphic. Title truncated to 60 chars, description to 120. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/og_image_generator.

PDF to Markdown: Convert a PDF document to clean, LLM-ready Markdown. Provide a direct URL to the PDF or base64-encoded file bytes. Auto-extracts headings, paragraphs, lists and tables. Ideal for feeding reports, papers and contracts into RAG pipelines. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/pdf_to_markdown.

PPTX to Markdown: Convert a PPTX (PowerPoint) presentation to Markdown. Provide a direct URL or base64-encoded file bytes. Each slide becomes a heading with its text content — pitch decks and slide reports become LLM-readable text. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/pptx_to_markdown.

QR/Barcode Generator: Generate a QR code or barcode as an image (SVG or PNG). Returns a base64-encoded image (MCP content type image). Symbologies: qrcode/qr, code128, code39, ean13, ean8, upca, upce, isbn10, isbn13, issn, itf, gs1-128, databar. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/qr_generator.

Short Link Creator: Create a permanent short link on freeq.one (e.g. https://freeq.one/MySlug). Optional: custom slug, expires_at (ISO date) for a TTL link that auto-expires — same price. Returns short_url plus a one-time manage_secret that gates FREE stats (GET /tools/shortlink_stats with X-Link-Secret) and FREE deletion of the link. Store the secret — it is shown only at creation. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/shortlink_create.

Short Link Stats: Click stats for a freeq.one short link: total clicks, last-30-day clicks, last click time. FREE for the link owner — pass the manage_secret returned at creation as the link_secret field. The paid call is for agents checking a link they did not create (liveness/traffic check). Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/shortlink_stats.

Token Price Lookup: Get the live USD price of any token by symbol (e.g. BTC, ETH, SOL, PEPE). Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/token_price.

Batch Semaphore Proof Verifier: Batch verify up to 10 Semaphore proofs in a single request. Returns per-proof results with total count and average duration. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/verify_batch.

Semaphore ZK Proof Verifier: Verify a Semaphore ZK proof locally using Groth16 (embedded official vkey). No external dependency. Send the proof object from @semaphore-protocol/proof generateProof(). Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/verify_semaphore.

Stablecoin Issuer / GENIUS / Reserve Verifier: Verify a stablecoin: issuer identity, GENIUS Act qualification status, and latest reserve attestation. Resolves the token from chain+address, a known symbol (USDC, USDT, PYUSD, USDS, FDUSD, USDe), or a tx hash. Free preview: preview=true validates the input and returns the issuer only — no payment required. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/verify_stablecoin.

World ID Proof Verifier: Verify a World ID 4.0 proof via the Worldcoin Developer Portal API. Generates an RP signature server-side, then proxies the full IDKit proof to developer.world.org. Returns { valid, nullifier, worldcoin_response }. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/verify_worldid.

Ethereum Address Checksum: Convert an Ethereum address to its EIP-55 checksummed form. SIWE messages require the checksummed address on line 2 before signing. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/wallet_checksum.

Wallet Portfolio: Get a complete wallet portfolio for an Ethereum address: native ETH balance, ERC-20 balances, NFT holdings, recent transfers. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/wallet_portfolio.

NIP-98 Nostr Auth Verifier: Verify a NIP-98 Nostr HTTP auth event. Returns the signer pubkey. Stateful replay protection: each event id can only be verified once. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/wallet_verify_nostr.

SIWE Signature Verifier: Verify a Sign-In-With-Ethereum (EIP-4361) signature. Stateless oracle: checks the signature against the message and returns the wallet address + chainId. Never mints sessions or consumes nonces. Get a checksummed address first via wallet_checksum. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/wallet_verify_siwe.

Solana Signature Verifier: Verify an ed25519 Solana wallet signature over a message containing a 'Nonce: <value>' line. Returns the signer pubkey. Consumes the nonce — one verification per nonce. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/wallet_verify_solana.

Ephemeral webhook receiver. Creates a single-use HTTPS URL that catches any POST (Stripe, GitHub, internal) for 1 hour; senders pay nothing. Read captured events for $0.01 per read, extend for $0.05/hour. Response returns hook_url, read_url, extend_url, expires_at.

Whale Alerts Scanner: Scan recent blocks for large ETH transfers involving an address. Filter by direction (in/out/both) and threshold. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/whale_alerts.

XLSX/CSV to Markdown + JSON: Convert an XLSX spreadsheet or CSV to Markdown table AND a JSON array of row objects in one call. Provide a direct URL or base64-encoded file bytes. All sheets are included; multi-sheet workbooks are flattened in sheet order. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/xlsx_to_markdown.