gpt-5.1
Auto-routeropenai/gpt-5.1
Context
400K
Max output
128K
Input / 1M
$1.25
Output / 1M
$10.00
Cached / 1M
$0.13
Cutoff
Oct 2024
About this model
GPT-5.1 is a frontier-grade OpenAI model with stronger general-purpose reasoning and better instruction following than GPT-5. It accepts text and image inputs and produces text outputs.
Best suited for
- Fast, intelligent model suitable for all-purpose tasks with improved reasoning over GPT-5
Built-in tools
Hosted by the gateway — enable them per request without wiring your own endpoint.
Capabilities
Vision
Accepts images alongside text in the same message.
Files
Accepts file attachments — PDFs, transcripts, spreadsheets.
Tools
Native function calling, so agents can invoke your endpoints.
System prompt
Honours a dedicated system role, separate from the user turn.
Reasoning
Emits a separate thinking pass before the answer.
Supported parameters
max_tokensMax Tokens LimitSpecifies the maximum number of text units (tokens) allowed in a response, limiting its length.
toolsLists tool definitions or capabilities available to the model.
tool_choiceDecides whether to use tools or just the model for generating responses.
response_typeDefines the format or type of the generated response.
parallel_tool_callsEnables parallel execution of tools, allowing multiple tools to run simultaneously.
reasoningControls the level of reasoning used by the model.
streamSends the response in real-time as it's being generated.
service_tiertemperature