# Stevens Keys

> License keys, edge validation and usage metering for paid MCP servers and APIs. Sell from your own site instead of a storefront. Preview, TEST MODE: no real charges, checkout is Stripe test mode only (test cards); creators can refund test sales (a full refund revokes the key), payouts via Stripe Connect are planned and not live (planned split 85/15 creator/platform). Accounts are verified for test mode by a Turnstile human check at sign-up (no email). Operated by Canada Site Ops, Ontario, Canada.

One call, `POST /v1/validate` with `Authorization: Bearer <license key>`, checks and meters a key: 200 allow, 403 deny, 401 missing. Revoked keys deny on the next validation (or within the optional `cache_ttl`, 30s default).

## Docs

- [Agent quickstart (Markdown)](https://stevens-keys.pages.dev/agent-quickstart.md): MCP and HTTP quickstart in plain Markdown, no signup
- [Creator docs](https://stevens-keys.pages.dev/docs): quickstart, verification, validation, revocation, quotas, API reference
- [OpenAPI 3.1 spec](https://stevens-keys.pages.dev/openapi.json): all live API routes (test mode)
- [Full text for LLMs](https://stevens-keys.pages.dev/llms-full.txt): docs, guides and every API operation in one file
- [API catalog (RFC 9727)](https://stevens-keys.pages.dev/.well-known/api-catalog): machine-readable list of the API's spec, docs and status
- [agents.json](https://stevens-keys.pages.dev/.well-known/agents.json): agent flows (demo key, validate, public stats) over the OpenAPI spec
- [Hosted MCP server](https://stevens-keys.pages.dev/mcp): Streamable HTTP, no auth, tools create_demo_key, validate_license_key, get_public_stats; resources/list exposes discovery docs (quickstart, llms.txt, OpenAPI, server card, api-catalog, docs.md) (test mode)
- [MCP server card](https://stevens-keys.pages.dev/.well-known/mcp/server-card.json): machine-readable description of the hosted MCP server
- [server.json](https://stevens-keys.pages.dev/server.json): MCP Registry-format server.json for the hosted MCP server (remote, streamable-http, no auth)
- [Agent card](https://stevens-keys.pages.dev/.well-known/agent-card.json): A2A-style agent card (HTTP API + hosted MCP; no A2A JSON-RPC endpoint)
- [Agent Skills index](https://stevens-keys.pages.dev/.well-known/agent-skills/index.json): Agent Skills Discovery (v0.2.0) index; skill: [stevens-keys SKILL.md](https://stevens-keys.pages.dev/.well-known/agent-skills/stevens-keys/SKILL.md)
- [AGENTS.md](https://stevens-keys.pages.dev/AGENTS.md): standing instructions for AI agents (how to start, machine files, rules)
- [Changelog (Atom)](https://stevens-keys.pages.dev/changelog.atom): feed of machine-facing changes; [security.txt](https://stevens-keys.pages.dev/.well-known/security.txt)
- [ai.txt](https://stevens-keys.pages.dev/ai.txt): automated-agent usage policy (all welcome); [JSON Feed](https://stevens-keys.pages.dev/feed.json): changelog as JSON Feed 1.1
- [Deprecated A2A agent.json](https://stevens-keys.pages.dev/.well-known/agent.json): same card as agent-card.json for A2A v0.2.x clients; prefer agent-card.json (v0.3+)
- [MCP tools catalog](https://stevens-keys.pages.dev/.well-known/mcp/tools.json): static list of the 3 hosted MCP tools with full inputSchema (no handshake required)
- [/.well-known/llms.txt](https://stevens-keys.pages.dev/.well-known/llms.txt): identical copy of llms.txt at the well-known path, for crawlers that probe there
- [/.well-known/openapi.json](https://stevens-keys.pages.dev/.well-known/openapi.json): identical copy of openapi.json at the well-known path, for scanners that probe there
- [ai-plugin.json](https://stevens-keys.pages.dev/.well-known/ai-plugin.json): plugin manifest pointing to the OpenAPI spec (no auth for demo/validate)
- [Sell API access with per-key billing in 10 minutes](https://stevens-keys.pages.dev/sell-api-access-per-key-billing): step-by-step guide
- [Gate snippet generator](https://stevens-keys.pages.dev/snippets): copy-paste validation code for Workers, Node/Express, Python, curl

## Guides

- [License keys for paid MCP servers](https://stevens-keys.pages.dev/mcp-license-keys)
- [License keys vs OAuth vs API keys](https://stevens-keys.pages.dev/mcp-license-keys-vs-oauth)
- [Keygen alternative: Stevens Keys vs Keygen, Lemon Squeezy, Gumroad](https://stevens-keys.pages.dev/keygen-alternative): sourced comparison (checked Oct 20, 2026), incl. when they are a better fit
- [Cryptlex alternative: Stevens Keys vs Cryptlex](https://stevens-keys.pages.dev/cryptlex-alternative): sourced comparison (checked Oct 21, 2026), incl. when Cryptlex is a better fit
- [Lemon Squeezy license keys alternative: Stevens Keys vs Lemon Squeezy](https://stevens-keys.pages.dev/lemon-squeezy-license-keys-alternative): sourced comparison (checked Oct 23, 2026), incl. when Lemon Squeezy is a better fit
- [MCP monetization FAQ](https://stevens-keys.pages.dev/mcp-monetization-faq)
- [Revenue calculator](https://stevens-keys.pages.dev/calculator)

## Markdown versions

Every main page has a clean Markdown copy at the same path plus `.md` (also linked from each page's `<link rel="alternate" type="text/markdown">` and HTTP Link header):

- [index.md](https://stevens-keys.pages.dev/index.md)
- [docs.md](https://stevens-keys.pages.dev/docs.md)
- [demo.md](https://stevens-keys.pages.dev/demo.md)
- [mcp-license-keys.md](https://stevens-keys.pages.dev/mcp-license-keys.md)
- [mcp-license-keys-vs-oauth.md](https://stevens-keys.pages.dev/mcp-license-keys-vs-oauth.md)
- [mcp-monetization-faq.md](https://stevens-keys.pages.dev/mcp-monetization-faq.md)
- [mcp-server-pricing-guide.md](https://stevens-keys.pages.dev/mcp-server-pricing-guide.md)
- [sell-api-access-per-key-billing.md](https://stevens-keys.pages.dev/sell-api-access-per-key-billing.md)
- [keygen-alternative.md](https://stevens-keys.pages.dev/keygen-alternative.md)
- [cryptlex-alternative.md](https://stevens-keys.pages.dev/cryptlex-alternative.md)
- [lemon-squeezy-license-keys-alternative.md](https://stevens-keys.pages.dev/lemon-squeezy-license-keys-alternative.md)

## Optional

- [Live sandbox demo](https://stevens-keys.pages.dev/demo)
- [Privacy](https://stevens-keys.pages.dev/privacy)
- [Terms](https://stevens-keys.pages.dev/terms)

## Quickstart for agents (no signup)
- API base: https://stevens-keys.pages.dev (all /v1/* endpoints; OpenAPI at https://stevens-keys.pages.dev/openapi.json)
- Get a 24h sandbox key: POST https://stevens-keys.pages.dev/v1/demo/keys
- Validate + meter: POST https://stevens-keys.pages.dev/v1/validate with header "Authorization: Bearer <key>" and JSON body {"units":1}
- Agent/bot traffic is welcome and never blocked; optional header "X-Client-Type: agent" labels it. Public aggregate stats: GET https://stevens-keys.pages.dev/v1/public-stats
- MCP: connect any MCP client to https://stevens-keys.pages.dev/mcp (Streamable HTTP, no auth). Tools: create_demo_key, validate_license_key, get_public_stats. resources/list returns discovery docs.
- Test mode only: no real charges, payouts not live.
- [/.well-known/ai.txt](https://stevens-keys.pages.dev/.well-known/ai.txt) and [/.well-known/agents.md](https://stevens-keys.pages.dev/.well-known/agents.md): copies of ai.txt and AGENTS.md at well-known paths, for scanners that probe there