Get started

From zero to first signed call in 10 minutes

Five short steps. No account upgrade required. Free tier covers everything in this guide.

  1. 1. Sign up

    Go to /account/signup and create a free account. Email + password. No credit card.

  2. 2. Mint a Lucairn API key

    On /account/dashboard, click Create API key. You'll get an lcr_live_* key — copy it immediately, it's only shown once. This is your gateway-auth key.

  3. 3. Get an upstream LLM key

    Lucairn proxies your favourite LLM. Free tier requires BYOK — bring your own Anthropic, OpenAI, Gemini, or Mistral key. Get one at console.anthropic.com or platform.openai.com.

  4. 4. Send your first call

    Replace lcr_live_... and sk-ant-... with your real keys. The response is identical to a direct Anthropic call — Lucairn is transparent on the wire — plus a metadata.dsa_compliance block with the cert URL.

  5. 5. Inspect the certificate

    Every successful call mints a Lucairn Certificate — Ed25519-signed proof of what was redacted, which sandbox served the response, and a content hash. Free tier gets a public HTML summary. Pro and Enterprise can fetch the full JSON certificate.

  6. 6. Verify offline (optional)

    A certificate is a self-contained Ed25519-signed payload. Pull the witness public key from /.well-known/veil-keys.json and verify with any Ed25519 library. The Python and TypeScript SDKs ship a verify_certificate helper.

Your first call

curl https://gateway.lucairn.eu/v1/messages \
  -H "Authorization: Bearer lcr_live_..." \
  -H "X-Upstream-Key: sk-ant-..." \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-sonnet-4-6",
    "max_tokens": 256,
    "messages": [
      {"role": "user", "content": "Classify this ticket: customer email is [email protected]"}
    ]
  }'

Open the certificate

# The response includes metadata.dsa_compliance.certificate_url.
# Open it in any browser, or fetch the public summary:
curl https://gateway.lucairn.eu/api/v1/veil/certificate/<request_id>/summary

Verify it

# Anyone can verify a certificate against the public witness key:
curl https://gateway.lucairn.eu/.well-known/veil-keys.json
# Or use the public verify page in the browser:
# https://lucairn.eu/en/verify

What works on the free tier today

Lucairn covers the boring 90% of LLM use — text in, text out, with redaction proof. A few edge cases (multimodal, tool-call DLP, prompt caching) are still on the roadmap. Read the matrix before relying on it for production.

  • Text messages via /v1/messages (Anthropic SDK shape)

    ✓

    Drop-in for the Anthropic SDK. Change base_url, keep your code.

  • Text messages via /v1/chat/completions (OpenAI SDK shape)

    ✓

    Drop-in for the OpenAI SDK. Same Bearer auth pattern.

  • Multi-provider routing via /api/v1/proxy/messages

    ✓

    Pick provider per request: Claude / OpenAI / Gemini / Mistral / self-hosted.

  • Streaming responses (SSE)

    !

    Anthropic /v1/messages and OpenAI /v1/chat/completions reject stream:true with HTTP 400 (per-chunk DLP gap). Lucairn-native /api/v1/proxy/messages supports SSE only when STREAMING_ENABLED=true on the gateway. Default deployment has it off — Roadmap.

  • Re-linking on free tier

    ✕ Roadmap

    Free tier responses contain placeholders. Pro and Enterprise can opt into automatic re-linking server-side.

  • Tool / function-call argument DLP

    ✕ Roadmap

    Tool definitions and function-call arguments are not sanitised today. Keep PII out of tools you pass through.

  • Image / file / audio attachments

    ✕ Roadmap

    Multimodal inputs have no Lucairn pipeline coverage yet.

Tool DLP and multimodal sanitisation are tracked on the roadmap. Subscribe to the changelog for ship dates. Read the changelog.

Next steps

Want to see this in action?

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