Claude Opus 4.8

Anthropic

Top-tier Anthropic model for the hardest reasoning and multi-step tasks.

anthropic/claude-opus-4-8

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Top-tier Anthropic model for the hardest reasoning and multi-step tasks.

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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.