Checkbox Docs

Subscription-law compliance as an API. Tell your AI coding agent "Add Checkbox to this project" and it handles the rest; or call the API yourself.

Checkbox checks a subscription business against automatic-renewal law — the federal Restore Online Shoppers' Confidence Act (ROSCA), California's Automatic Renewal Law (Bus. & Prof. Code § 17600 et seq.), New York GBL § 527-a and the other state laws — across the whole lifecycle: sign-up disclosure and consent → acknowledgment email → trial and renewal reminders → online cancellation. It tells you, or your coding agent, exactly what to change, then checks again. Free to start; no credit card.

#The fastest path: let your agent do it

Open your project in Claude Code, Cursor, Copilot or any coding agent and say:

Add Checkbox (https://checkbox.site/docs) to this project and make our subscription checkout compliant.

What happens next:

1. One call. The agent calls the setup_checkbox tool of the MCP server (or the device-login API; the checkbox init CLI does the same once it is published).
2. One click from you. A link opens in your browser: sign in with your email, GitHub or Google and click Approve. That is the only thing a human has to do.
3. Checkbox learns the business. The agent gets test-mode keys in .env.local, the Checkbox snippet goes into your root layout, and Checkbox registers your site, fetches your Terms, refund and cancellation policies and runs the first checks. With your permission it runs a synthetic test subscription in Stripe test mode: sign-up, emails, trial end and renewal on a test clock, and online cancellation.
4. A compliance plan. The agent reads an ordered, machine-readable plan: each task names the legal requirement and citation, where to change it (file, selector, Stripe setting) and the exact change.
5. Fix, verify, repeat. The agent applies a task and calls verify; Checkbox re-checks right away and returns the updated plan, until every check Checkbox can observe passes. You get a short email: "Claude Code set up Checkbox for yoursite.com", with a link to review. Checkbox is an automated assessment, not legal advice.

Every API response carries a next_action, so the agent never has to guess the next call. Read the agent loop for the details, or copy a ready-made prompt from Build with AI.

#Or integrate it yourself

#How Checkbox decides

Every verdict comes from one rules engine over a versioned legal catalog: each requirement has a citation, an effective date and the conditions under which it applies (free trial, term length, online sign-up…). The catalog currently holds 196 requirements in 29 jurisdictions (catalog version 2026.10.31.1, last verified against primary sources on 2026-10-29; rules version 1.3.0). The same engine judges preflight checks, synthetic-shopper scans, test subscriptions and fixes, so what passes in your editor passes in monitoring.

Checkbox collects evidence from four sources — a synthetic shopper that visits your checkout from each state, the JavaScript snippet on your own pages, your billing platform's settings and webhooks, and the emails your subscribers receive — and stores it in a hash-chained, signed evidence vault.

#For AI agents

• Every page is Markdown at the same URL plus .md (this one: /docs.md); the index is /llms.txt and everything in one file is /llms-full.txt.
• The API contract is OpenAPI 3.1 at https://app.checkbox.site/v1/openapi.json. Operation ids (createSite, checkStripeCheckoutSession…) are also the SDK method names and the agent-facing names in next_action.
• Drop-in instructions for your repository: AGENTS.md template, Claude skill and Cursor rules.

Checkbox is compliance software, not a law firm; nothing in these docs is legal advice (details). For AI agents: every page is available as Markdown at the same URL plus .md; the index is /llms.txt.