Kraken API documentation

Last updated: 16 April 2026

Overview

Kraken is a managed LLM API gateway. One OpenAI-compatible endpoint routes your requests to every major LLM provider with a task-aware router that picks the best-fit model for every prompt.

If you already use OpenAI or any OpenAI-compatible SDK, switching to Kraken is a one-line change — update the base_url, keep everything else the same.

Quickstart

1. Get an API key

Sign up at gammainfra.com — email + password, one-time verification link, no credit card. New accounts come with $3.00 of free credit, enough to try the router end-to-end. Your API key is shown once after you click the verification link — store it somewhere safe. Need more keys later? Issue and revoke them from the dashboard.

2. Make your first call

curl -s -X POST https://gammainfra.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer sk-kraken-..." \
  -d '{
    "model": "kraken/auto",
    "messages": [{"role": "user", "content": "Explain transformers in one paragraph."}]
  }'

The response is identical to OpenAI’s format. kraken/auto lets the router pick the best model for your prompt.

3. Drop-in replacement

from openai import OpenAI

client = OpenAI(
    api_key="sk-kraken-...",
    base_url="https://gammainfra.com/v1",
)

response = client.chat.completions.create(
    model="kraken/auto",
    messages=[{"role": "user", "content": "Hello"}],
)
print(response.choices[0].message.content)

The same pattern works with LangChain, LlamaIndex, and any other OpenAI-compatible library.

Authentication

Every request (except /v1/models and /v1/status) requires a Bearer token:

Authorization: Bearer sk-kraken-...

Keys are prefixed sk-kraken-. The plaintext is only returned on creation — Kraken stores a bcrypt hash. Create additional keys or revoke old ones from the dashboard.

Smart routing

Send model: "kraken/auto" and the router classifies your prompt into one of 10 task types, then dispatches to the best-fit model for that type. If the primary model is unavailable, Kraken falls back through a chain of 3–4 models automatically.

Model names

Smart aliases (recommended)

Pin a specific model

Prefix any model with its provider slug:

openai/gpt-5.4
openai/gpt-5.4-mini
openai/gpt-5.4-nano
openai/gpt-5-mini
anthropic/claude-opus-4-6
anthropic/claude-sonnet-4-6
anthropic/claude-haiku-4-5
google/gemini-3.1-pro-preview
google/gemini-3-flash-preview
google/gemini-2.5-pro
google/gemini-2.5-flash
mistral/mistral-large-2512
mistral/mistral-small-2603
mistral/codestral-2508
mistral/devstral-2512
groq/llama-3.3-70b-versatile
groq/llama-3.1-8b-instant
groq/gpt-oss-120b
deepseek/deepseek-chat
deepseek/deepseek-reasoner
grok/grok-4
grok/grok-4-fast
grok/grok-code-fast-1

For the full, authoritative list:

curl -s https://gammainfra.com/v1/models | jq .

Streaming

Streaming works exactly like OpenAI — set stream: true and read Server-Sent Events. All providers are normalised to the OpenAI SSE format, so your existing code works unchanged.

stream = client.chat.completions.create(
    model="kraken/auto",
    messages=[{"role": "user", "content": "Write a haiku about distributed systems."}],
    stream=True,
)
for chunk in stream:
    print(chunk.choices[0].delta.content or "", end="", flush=True)

Headers

Request headers

Response headers

Credits & pricing

• Credits are USD-denominated. $1.00 = 100 credits.
• New accounts start with $3.00 of free credit.
• 0% markup on tokens — you pay provider list prices.
• 5% fee on credit top-ups (3% launch-window rate during the first 60 days).
• Minimum top-up: $10. No subscription. Credits never expire.

Approximate cost per 1M tokens

Costs above are provider list prices — Kraken passes them straight through. The only Kraken fee is the 5% we charge when you top up credits (3% during the launch window). For the full cost table and legal terms, see the Terms of Service.

Reasoning tokens on gpt-5 and DeepSeek-Reasoner

OpenAI’s gpt-5 family and DeepSeek’s reasoner model bill hidden “reasoning tokens” in addition to the visible output. Reasoning tokens are the model’s chain-of-thought and are not returned in the response but are counted in usage.completion_tokens.

Kraken silently caps gpt-5 reasoning at max_completion_tokens=2048 when the caller omits the parameter, and picks a conservative reasoning_effort based on the router’s logical label (chat → low, code/summarize → medium, reasoning/math → high). This prevents the “‘hi’ burned 320 reasoning tokens” pathology from reaching your bill, but you should still budget 2–4× visible output tokens for gpt-5-family calls in batch sizing. Inspect usage.completion_tokens_details.reasoning_tokens in any response to see the split.

Check your balance

curl -s https://gammainfra.com/v1/billing/balance \
  -H "Authorization: Bearer sk-kraken-..."

{"balance_usd": 0.97, "customer_id": "..."}

Top up

Top up your balance from dashboard.gammainfra.com → Top up. You’ll be redirected to Stripe’s hosted checkout and back to your dashboard once payment clears. Card data is handled by Stripe — Kraken never sees it. Amount range: $5 – $1000; your balance updates within seconds of Stripe’s confirmation.

Bring your own key (BYOK)

Optional. By default Kraken uses its own provider API keys on your behalf — one Kraken key, every model. If you already have a direct relationship with a provider, add your own key at dashboard.gammainfra.com → Provider Keys and Kraken will route requests to that provider through your key instead.

• Your key is stored encrypted at rest (Fernet).
• You pay that provider directly for requests that use your key; the Kraken fee still applies.
• Revoking or deleting your key falls back to managed routing (if the provider offers managed access) or skips that provider.
• Supported providers: openai, anthropic, google, mistral, groq, deepseek, grok.

Add a key

curl -s -X POST https://gammainfra.com/v1/provider-keys \
  -H "Authorization: Bearer sk-kraken-..." \
  -H "Content-Type: application/json" \
  -d '{"provider_name": "openai", "api_key": "sk-..."}'

List your keys

curl -s https://gammainfra.com/v1/provider-keys \
  -H "Authorization: Bearer sk-kraken-..."

Delete a key

curl -s -X DELETE https://gammainfra.com/v1/provider-keys/openai \
  -H "Authorization: Bearer sk-kraken-..."

Or manage all of this from dashboard.gammainfra.com → Provider Keys.

BYOK pricing — separate prepaid balance

BYOK traffic uses its own prepaid balance, distinct from your managed credits. Top it up from the dashboard's BYOK Balance tab or via POST /v1/billing/byok/checkout (minimum $5, no top-up fee). Each BYOK-routed request deducts a small per-request fee:

• 2% of the retail provider cost (standard rate).
• 1% during the launch window (first 60 days).
• When the BYOK balance hits $0, BYOK-routed requests return 402 byok_balance_empty — top up to resume. Managed credits are not touched.
• You'll receive one low-balance email when your BYOK balance drops below 20% of your last top-up (7-day cooldown between reminders).

curl -s -X POST https://gammainfra.com/v1/billing/byok/checkout \
  -H "Authorization: Bearer sk-kraken-..." \
  -H "Content-Type: application/json" \
  -d '{"amount_usd": 25.0}'

Check your BYOK balance:

curl -s https://gammainfra.com/v1/billing/byok/balance \
  -H "Authorization: Bearer sk-kraken-..."

Error codes

Error responses use a consistent JSON shape:

{
  "error": {
    "message": "Human-readable description",
    "type": "error_type",
    "code": "machine_readable_code",
    "request_id": "uuid"
  }
}

Rate limits

• Chat completions: no hard Kraken-side limit today. Provider-side rate limits pass through as 429 responses with any Retry-After header the provider returned.
• If you expect high-volume traffic, email hello@gammainfra.com ahead of time.

Status

Live per-provider uptime, latency, and error counts are published:

• status.gammainfra.com — human-readable HTML dashboard, auto-refreshes every 30 s
• GET /v1/status — same data as JSON, safe to poll from your own monitoring

Both endpoints are public (no auth). Each provider is marked operational, degraded, or outage based on the rolling 24 h request log plus a live health-check ping.

Support

Email hello@gammainfra.com. Include the X-Kraken-Request-Id response header from any failing request — it lets us trace the exact path the request took through the router.

For policy and billing terms, see Terms and Privacy.