Chat Completions

Send messages to POST https://api.apione.ai/v1/chat/completions using the OpenAI-compatible chat format. Verify a minimal request before adding model-specific parameters.

Send a request

Set APIONE_API_KEY and APIONE_MODEL using the quickstart. Copy the model ID from the available model list and check the key’s permissions and billing group.

: "${APIONE_API_KEY:?Set APIONE_API_KEY first}"
: "${APIONE_MODEL:?Set APIONE_MODEL first}"

curl -sS https://api.apione.ai/v1/chat/completions \
  -H "Authorization: Bearer $APIONE_API_KEY" \
  -H "Content-Type: application/json" \
  --data "{\"model\":\"$APIONE_MODEL\",\"messages\":[{\"role\":\"user\",\"content\":\"Suggest three navigation groups for a documentation site.\"}]}"

For multi-turn conversations, your application sends the necessary history in messages. Do not assume the next request automatically carries the previous context. For SDK examples, see Python and Node.js.

Common request fields

Field	Type	Purpose
`model`	string	Required model ID available to the key
`messages`	object[]	Required message history with `role` and `content`
`stream`	boolean	Enable SSE; defaults to `false`
`max_tokens`	integer	Output limit; support and valid values depend on the model
`temperature`	number	Sampling control; support and range depend on the model
`top_p`	number	Alternative sampling control; usually avoid changing it together with `temperature`
`tools` / `tool_choice`	object[] / string or object	Tool definitions and selection, requiring model support
`response_format`	object	JSON or JSON Schema output, requiring model support

Recheck parameters when switching models. For unsupported parameters, remove optional fields and verify the minimal request before restoring them individually.

Read the response

A text response has the following shape. Values are illustrative:

{
  "model": "YOUR_MODEL_ID",
  "choices": [
    {
      "message": {"role": "assistant", "content": "Getting started, API reference, and integrations."},
      "finish_reason": "stop"
    }
  ],
  "usage": {"prompt_tokens": 20, "completion_tokens": 10, "total_tokens": 30}
}

Field	How to read
`choices[].message.content`	Reply text; may be empty for tool calls
`choices[].message.tool_calls`	Tool calls the model asks the application to execute
`choices[].finish_reason`	Examples include `stop`, `length`, `tool_calls`, and `content_filter`
`usage`	Input, output, and total tokens; cache and other additional fields vary by model
`model`	Model information in the response

When finish_reason is length, check output limits and whether the content is complete; truncated JSON cannot be used directly for downstream business. Tool calls and JSON validation: see structured output and tools; continuous incremental reception: see streaming. See the APIONE Chat reference for complete fields and troubleshooting for failed calls.

Addresses and authentication

Model APIs

Output and advanced usage

Image APIs

Video APIs

Send a request

Common request fields

Read the response