Fable becomes an advisor to Opus 5.5 in Claude Code

Claude Code added the /advisor fable command, which attaches Fable to a session as a second model that Opus 5.5 consults on its own while continuing to write code. The advisor runs only through the Anthropic API and is unavailable on Bedrock, Google Cloud and Microsoft Foundry.

• The /advisor fable command pairs Fable as an advisor while Opus 5.5 writes the code
• Fable is called at decision points rather than every turn, cutting session costs
• Enabling it requires one-time consent via /model fable
• The advisor is unavailable on Amazon Bedrock, Google Cloud and Microsoft Foundry