Use cases
What the API is used for
One OpenAI-compatible endpoint set covering conversation, images in, speech in and video out. Each workload below has at least one model serving it today.
Generated from the live catalogue, so a workload appears here only while a model serves it.
Open LLMs serves four kinds of workload today: chat and tool-calling, reading screenshots and documents, transcribing speech, and generating video. Each is reached through the OpenAI-compatible endpoint for that task, with the model named in the request.
Chat, tool calls and agents
Reached through /v1/chat/completions.
Conversation, instruction-following and function calling — the workload most people mean by 'an LLM API'. This is the drop-in case: point an existing OpenAI client here and change the model id.
Models serving it: GLM-4.5-Air ($1.50 / 1M tokens), Qwen-2.5 ($0.15 / 1M tokens).
What it is not. Not for tasks that need a frontier closed model's reasoning. Where one is genuinely better, the cheaper request is not the better one.
Video generation
Generate video from a text prompt or an input image.
Models serving it: Wan2.1-VACE Video ($50.00 / 1M tokens).
What it is not. Slow and expensive relative to everything else here. Worth checking the rate on the pricing page before designing around it.
Screenshots and documents
Reached through /v1/chat/completions.
Send an image with your prompt and get text back — reading a screenshot, pulling fields off an invoice or a form, describing a chart. Same chat-completions shape, with an image part in the message.
Models serving it: Qwen-3.5 ($0.15 / 1M tokens).
What it is not. Not an OCR engine. It reads a document to answer a question about it; it does not produce a faithful character-level transcription of a scan.
Speech to text
Reached through /v1/audio/transcriptions.
Turn recordings into text — meetings, interviews, voice notes, call audio. Billed per minute of audio rather than per token, so the cost of a job is knowable before you run it.
Models serving it: Whisper Large v3 ($0.004 / minute).
What it is not. Not real-time streaming transcription. You upload a file and get a transcript; there is no live socket.
How do I choose between them?
By what you are sending, not by price — a speech model cannot answer a chat request, so most of the choice is made for you. Within a workload, run the cheaper model first and move only if its output is not good enough for yours. That order costs you one experiment; the reverse costs you the difference on every request in the meantime.
Every model, rate and context window is on the catalogue and the pricing page. What each endpoint accepts is in the API reference, and what it returns when something is wrong is on the errors page.