1. Introduction
GPT 5.5 is a ModelVia model.GPT 5.5 is OpenAI's flagship model for advanced reasoning, agentic coding, multilingual generation, tool use, and multimodal workflows.
This page combines the model overview, interactive testing surface, request schemas, and production API workflow in one place.
2. Key Features & Innovations
- • Reasoning
- • Agents
- • Tool Calling
- • Multimodal
3. Model Architecture & Technical Details
GPT 5.5 is OpenAI's flagship model for advanced reasoning, agentic coding, multilingual generation, tool use, and multimodal workflows.
Prompt
Describe the result you want the model to create.
System instructions
Optional system-level behavior instructions.
Reasoning effort
Controls how much reasoning the model should apply when supported.
Temperature
Higher values make the response more varied.
Max output tokens
Maximum response length. GPT 5.5 supports up to 128K output tokens.
4. Performance Highlights
- • Provider limits and pricing can vary by route configuration.
5. Intended Use & Applications
Reasoning
Agents
Tool Calling
Multimodal
