One key, both protocols.

Getting a key

Keys are created and revoked in the dashboard at www.sideren.io/dashboard/keys. A key is shown once at creation — store it somewhere safe. Keys start with sdn_.

Treat keys as secrets. Set them through environment variables rather than committing them, and rotate from the dashboard if one leaks.

How to present the key

Protocol	Endpoint	Header
Anthropic Messages	`/v1/messages`	`x-api-key: sdn_...`
OpenAI Chat Completions	`/v1/chat/completions`	`Authorization: Bearer sdn_...`
OpenAI Responses	`/v1/responses`	`Authorization: Bearer sdn_...`
Embeddings / Completions / Batches	`/v1/...`	`Authorization: Bearer sdn_...`

Every endpoint accepts either presentation — x-api-key or Authorization: Bearer — so a client that can only set one auth header works everywhere. The table shows each protocol’s native convention. GET /v1/models needs no key at all.

Examples

Anthropic — x-api-key

curl https://api.sideren.io/v1/messages \
  -H "x-api-key: sdn_your_key" \
  -H "content-type: application/json" \
  -d '{"model":"@sdn/gpt-oss-120b","max_tokens":256,"messages":[{"role":"user","content":"Hi"}]}'

OpenAI — Authorization: Bearer

curl https://api.sideren.io/v1/chat/completions \
  -H "authorization: Bearer sdn_your_key" \
  -H "content-type: application/json" \
  -d '{"model":"@sdn/gpt-oss-120b","messages":[{"role":"user","content":"Hi"}]}'

Failure modes

A missing or malformed key returns 401 with an error body shaped for the protocol you called.
A valid key naming a model that does not exist in the catalog returns 404 — check the id against GET /v1/models.

See Errors for the full status-code reference and body shapes.

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One key, both protocols.

Getting a key

How to present the key

Examples

Failure modes

​Getting a key

​How to present the key

​Examples

​Failure modes

Getting a key

How to present the key

Examples

Failure modes