Anthropic Claude: Claude Opus 5.5 API
Claude Opus 5.5 by Anthropic Claude. 1,000,000 token context. Call it via ePhone AI's unified API.
- Context window: 1,000,000 tokens
- Max output: 128,000 tokens
- Input: text, image
- Output: text
- Reasoning: Supported
- Tool calling: Supported
- File input: Supported
- Released: 2026-09-21
- Knowledge cutoff: 2025-11-30
Frequently Asked Questions
What is the context window of Claude Opus 5.5?
Claude Opus 5.5 supports a context window of up to 1,000,000 tokens.
Does Claude Opus 5.5 support function calling?
Yes. Claude Opus 5.5 supports tool / function calling.
Does Claude Opus 5.5 support reasoning?
Yes. Claude Opus 5.5 is a reasoning-capable model.
What is the knowledge cutoff of Claude Opus 5.5?
The knowledge cutoff of Claude Opus 5.5 is 2025-11-30.