GPT 5.4

OpenAI

OpenAI flagship model for general-purpose chat, tools, and structured output.

openai/gpt-5.4

Conversation

Start a conversation

OpenAI flagship model for general-purpose chat, tools, and structured output.

Enter to send · Shift+Enter for a new line

Prompt

System prompt

User prompt prefix

Prepended to every user message sent to the API.

Append previous messagesWhen off, only the system prompt and latest user message are sent.

Output

Thinking processEnable extended reasoning when the model supports it.

Max tokens

Stream responseShow tokens as they arrive

Tools

Tools (JSON)

Tool choice

Uses POST /v1/chat/completions with your Unifically API key. Supports system and user prompts, tools, streaming, and thinking when available.