Claude Fable 5.2 from Anthropic is now available on AI Gateway.
Fable 5.2 is built for open-ended technical work and improves on earlier Fable models in coding, reasoning, and vision. It can run long, ambiguous tasks unattended, and works as an orchestrator that hands simpler tasks to smaller models, or as an advisor that other Claude models consult on harder problems. It also communicates more clearly and generates output faster than earlier Fable models. Effort runs from low to max, with high as the API default.
Fable 5.2 has cybersecurity and biology safety classifiers enabled. Access to Claude Fable 5.2 requires data retention. Anthropic does not support Zero Data Retention for the model. Prompts and completions are retained for 30 days and are not used to train Claude. If your team has ZDR turned on, AI Gateway returns an error instead of sending the request to Fable 5.2.
To keep requests served when a classifier is triggered, use model fallbacks. Add a models array to providerOptions.gateway, and AI Gateway tries each model in order when the cybersecurity classifier declines a request.
Call it through the AI SDK, the Chat Completions, Responses, and Anthropic Messages APIs, or a coding agent connected to AI Gateway. Use anthropic/claude-fable-5.2 as the model name:
This request falls back to Opus 5.5, then Sonnet 5.5, if the cybersecurity classifier declines it. The models option works the same way on every AI Gateway API format.
To use it in Claude Code, Codex, Cursor, and more, install the latest Vercel CLI and run setup:
Try Claude Fable 5.2 in the model playground. AI Gateway provides a unified API for calling models, tracking usage and cost, and configuring retries, failover, and performance optimizations for higher-than-provider uptime. It includes built-in custom reporting, Zero Data Retention support, budgets for API keys, routing rules, and more.
AI Gateway reflects provider pricing with no markup and does not charge a platform fee on inference, including on Bring Your Own Key (BYOK) requests.
You can view all language models available on AI Gateway.