x402.freeq.one

**43 pay-per-call APIs for AI agents — blockchain data, web scraping, document/PDF-to-Markdown conversion, ZK proof verification, image & 3D model generation, QR/diagram/OG-image rendering, LLM chat, gift cards, short links, ephemeral webhook receivers. Settled in USDC on Base via the x402 payment protocol.** No accounts, no API keys: agents pay per request via the x402 protocol.

Pay-per-call MCP.No accounts. No logins. No keys.

43 tools on Base via the Coinbase CDP x402 facilitator. Agents pay per request in USDC — settled on-chain in seconds. No API keys to provision, no subscriptions to manage.

How it works

The x402 protocol turns HTTP 402 Payment Required into an onchain payment flow.

1

Agent reads metadata

GET the endpoint. Receive an OpenAPI spec + x402 payment details (payTo, amount, asset, network).

2

Sees 402 response

Server returns HTTP 402 with a signed payment requirement in USDC on Base or Solana.

3

Signs & pays onchain

Agent wallet broadcasts a USDC microtransaction on Base. No human needed, no account to create.

4

Gets the result

Server verifies the payment header and returns the API response. Done.

All APIs

Each tool is a standalone paid endpoint. Browse the catalog — click any card for details.

[

markdown $0.002

Fetch a URL and convert its main content to clean, LLM-ready Markdown. Strips nav/ads/sidebars.

POST Details →

](https://x402.freeq.one/tools/markdown.html)[

token_price $0.002

Get the live USD price of any token by symbol (e.g. BTC, ETH, SOL, PEPE).

GET Details →

](https://x402.freeq.one/tools/token_price.html)[

wallet_portfolio $0.002

Get a complete wallet portfolio: native ETH balance, ERC-20 balances, NFT holdings, recent transfers.

POST Details →

](https://x402.freeq.one/tools/wallet_portfolio.html)[

whale_alerts $0.002

Scan recent blocks for large ETH transfers involving an address. Filter by direction and threshold.

POST Details →

](https://x402.freeq.one/tools/whale_alerts.html)[

cross_chain_balance $0.002

Aggregate native balance and token/NFT counts for an address across eth, arb, base, polygon, opt.

POST Details →

](https://x402.freeq.one/tools/cross_chain_balance.html)[

changelog_openapi $0.005

Diff two OpenAPI specs and generate a structured breaking-change changelog. Deterministic, no LLM.

POST Details →

](https://x402.freeq.one/tools/changelog_openapi.html)[

changelog_git $0.005

Diff git commits and generate a structured breaking-change changelog. Provide repo URL + base commit.

POST Details →

](https://x402.freeq.one/tools/changelog_git.html)[

mermaid $0.005

Render a Mermaid diagram to an image (PNG or SVG). Returns base64-encoded image.

POST Details →

](https://x402.freeq.one/tools/mermaid.html)[

html_to_markdown $0.002

Convert an HTML string to clean, LLM-ready Markdown. Handles headings, links, tables, code blocks.

POST Details →

](https://x402.freeq.one/tools/html_to_markdown.html)[

qr_generator $0.002

Generate a QR code or barcode as an image (SVG or PNG). QR, Code128, EAN, UPC, ISBN, and more.

GET Details →

](https://x402.freeq.one/tools/qr_generator.html)[

og_image_generator $0.002

Generate an Open Graph social-card image (1200x630 PNG) from a title and description.

GET Details →

](https://x402.freeq.one/tools/og_image_generator.html)[

jobs $0.002

Search live job postings by keywords and locations. Returns structured results: title, company, location, salary, and more.

POST Details →

](https://x402.freeq.one/tools/jobs.html)[

verify_semaphore $0.002

Verify a Semaphore ZK proof locally using Groth16 (embedded official vkey). No external dependency — pure on-device verification.

POST Details →

](https://x402.freeq.one/tools/verify_semaphore.html)[

verify_worldid $0.005

Verify a World ID 4.0 proof via the Worldcoin Developer Portal API. Generates RP signature, proxies to Worldcoin, returns nullifier + validity.

POST Details →

](https://x402.freeq.one/tools/verify_worldid.html)[

verify_batch $0.005

Batch verify up to 10 Semaphore proofs in a single request. Returns per-proof results with timing stats.

POST Details →

](https://x402.freeq.one/tools/verify_batch.html)[

wallet_verify_siwe $0.002

Verify a Sign-In-With-Ethereum (EIP-4361) signature as a paid oracle: returns wallet address + chainId, mints nothing.

POST Details →

](https://x402.freeq.one/tools/wallet_verify_siwe.html)[

wallet_verify_nostr $0.002

Verify a NIP-98 Nostr HTTP auth event with replay protection (each event id verifies once). Returns the signer pubkey.

POST Details →

](https://x402.freeq.one/tools/wallet_verify_nostr.html)[

wallet_verify_solana $0.002

Verify an ed25519 Solana wallet signature over a nonce-bearing message. One verification per nonce; returns signer pubkey.

POST Details →

](https://x402.freeq.one/tools/wallet_verify_solana.html)[

wallet_checksum $0.002

Convert an Ethereum address to its EIP-55 checksummed form — required on SIWE message line 2 before signing.

POST Details →

](https://x402.freeq.one/tools/wallet_checksum.html)[

llm_chat $0.002

Chat with a language model. OpenAI-compatible /v1/chat/completions. 50+ models — free (auto, eco, premium) are $0, paid models at cost.

POST Details →

](https://x402.freeq.one/tools/llm_chat.html)[

pdf_to_markdown $0.01

Convert a PDF document to clean, LLM-ready Markdown. Direct URL or base64 file bytes. Reports, papers and contracts become RAG-ready text.

POST Details →

](https://x402.freeq.one/tools/pdf_to_markdown.html)[

docx_to_markdown $0.005

Convert a DOCX (Word) document to Markdown. Contracts, resumes, reports and letters — headings, lists and tables preserved.

POST Details →

](https://x402.freeq.one/tools/docx_to_markdown.html)[

pptx_to_markdown $0.005

Convert a PPTX (PowerPoint) presentation to Markdown. Each slide becomes a heading — pitch decks turn into LLM-readable text.

POST Details →

](https://x402.freeq.one/tools/pptx_to_markdown.html)[

xlsx_to_markdown $0.005

Convert XLSX or CSV to a Markdown table AND a JSON array of row objects in one call. All sheets included, flattened in order.

POST Details →

](https://x402.freeq.one/tools/xlsx_to_markdown.html)[

epub_to_markdown $0.005

Convert an EPUB e-book to Markdown. Chapters become headings; metadata included — feed whole books into LLM context.

POST Details →

](https://x402.freeq.one/tools/epub_to_markdown.html)[

document_to_markdown $0.01

Convert any document to Markdown with automatic format detection — pdf, docx, pptx, xlsx, csv, epub, html, text. One endpoint for all of them.

POST Details →

](https://x402.freeq.one/tools/document_to_markdown.html)[

verify_stablecoin $0.005

Verify a stablecoin: issuer identity, GENIUS Act qualification status, and latest reserve attestation. Resolves the token from chain+address, a known symbol, or a tx hash. Free preview validates the input and returns the issuer only.

POST Details →

](https://x402.freeq.one/tools/verify_stablecoin.html)[

giftcard_buy dynamic

Buy a digital gift card code (Foot Locker, Target, AMC, 1000+ brands). Search the catalog free, pay the face value + fee in USDC — code delivered instantly, settled on Base via x402.

POST Details →

](https://x402.freeq.one/tools/giftcard_buy.html)[

shortlink_create $0.002

Create a permanent short link on freeq.one (custom or random slug, optional TTL expiry). Returns the short URL plus a one-time manage_secret that gates free stats and deletion of the link.

POST Details →

](https://x402.freeq.one/tools/shortlink_create.html)[

shortlink_stats $0.001

Click stats for a freeq.one short link: total clicks and last-30-day daily counts. Free for the link owner (pass the manage_secret); paid calls serve agent link-verification flows.

GET Details →

](https://x402.freeq.one/tools/shortlink_stats.html)[

webhook_catch $0.05

Ephemeral webhook receiver: creates a single-use HTTPS URL that catches any POST (Stripe, GitHub, internal) for up to an hour. Sender ingest is free; reads are $0.01, +1h extends are $0.05. In-memory, auto-deletes on expiry.

POST Details →

](https://x402.freeq.one/tools/webhook_catch.html)[

RaaS — Referral-as-a-Service: short-link referrals that turn verified on-chain x402 payments on Base into service credits. Provision a project with one paid x402 call to /tools/raas_project_provision ($0.05, one-time) and get back a project_id plus an API key; mint links at freeq.one/{code} and read stats with that key at no extra cost. Rewards are credits redeemable for API access, never USDC.

API Details →

](https://x402.freeq.one/tools/raas.html)[

google_serp $0.02

Live Google organic results for any keyword. Returns top 10 titles, URLs, snippets, and rank. Priced below typical SEO-data APIs.

POST Details →

](https://x402.freeq.one/tools/google_serp.html)[

keyword_volume $0.03

Google search volume, CPC, and competition for up to 100 keywords. Priced below typical SEO-data APIs.

POST Details →

](https://x402.freeq.one/tools/keyword_volume.html)[

keyword_ideas $0.05

Generate keyword ideas from a seed keyword with volume data. Priced below typical SEO-data APIs.

POST Details →

](https://x402.freeq.one/tools/keyword_ideas.html)[

domain_competitors $0.05

Find organic competitors for any domain. Priced below typical SEO-data APIs.

POST Details →

](https://x402.freeq.one/tools/domain_competitors.html)[

domain_keywords $0.05

Get all keywords a domain ranks for with position and volume. Priced below typical SEO-data APIs.

POST Details →

](https://x402.freeq.one/tools/domain_keywords.html)[

backlinks_overview $0.05

Backlink overview for any domain — referring domains, backlink count, authority. Priced below typical SEO-data APIs.

POST Details →

](https://x402.freeq.one/tools/backlinks_overview.html)[

search_intent $0.02

Detect search intent (informational, transactional, commercial) for a keyword. Priced below typical SEO-data APIs.

POST Details →

](https://x402.freeq.one/tools/search_intent.html)[

image_generate $0.02

Text-to-image generation (fast tier, 2-6s). Returns a permanent hosted image URL. Game assets, avatars, illustrations, concept art.

POST Details →

](https://x402.freeq.one/tools/image_generate.html)[

image_generate_quality $0.09

Premium text-to-image generation (10-30s) — better prompt adherence and typography. Returns a permanent hosted image URL.

POST Details →

](https://x402.freeq.one/tools/image_generate_quality.html)[

photo_to_3d_fast $0.15

Photo to 3D model (fast tier, 10-30s). Single 2D image URL to a textured low-poly GLB mesh + preview thumbnail. Game-ready — Three.js, Unity, Godot.

POST Details →

](https://x402.freeq.one/tools/photo_to_3d_fast.html)[

photo_to_3d_hq $0.50

Photo to 3D model (high-detail tier, 1-3 min). High-poly textured GLB with PBR-like shading + preview thumbnail. Game-ready — Three.js, Unity, Godot.

POST Details →

](https://x402.freeq.one/tools/photo_to_3d_hq.html)