Claude Fable 5 now available on AI Gateway
Quick Answer
This paper shows that Claude Fable 5 from Anthropic is now available on AI Gateway, enhancing performance on complex tasks with improved first-shot correctness and reduced human intervention.
Quick Take
Claude Fable 5 from Anthropic is now available on AI Gateway, enhancing performance on complex tasks with improved first-shot correctness and reduced human intervention. The model features built-in classifiers to mitigate misuse risks and retains prompts for 30 days without zero data retention support. AI Gateway offers a unified API for model management without platform fees.
Key Points
- Fable 5 excels in long-running, multi-step tasks with higher first-shot correctness.
- Built-in classifiers prevent misuse in cybersecurity and biology applications.
- Prompts and completions are retained for 30 days, with no zero data retention.
- AI Gateway offers a unified API for model usage tracking and cost management.
- No platform fees on inference, including Bring Your Own Key requests.
Article Content
From source RSS / original summaryClaude Fable 5 from Anthropic is now available on . A Mythos-class model, Fable 5 is a notable step up over prior Claude models on long-running, ambiguous, multi-step tasks, executing end-to-end on work that previously required frequent human check-ins. AI GatewayThe model sustains productive output across multi-day runs and dependably dispatches parallel sub-agents, and lower effort settings often match what prior Claude models produced at their highest effort.
Code review, bug-finding, and repository investigation are stronger, and first-shot correctness on complex problems is noticeably higher. Fable 5 ships with blocking classifiers in place that refuse offensive cybersecurity, biology, and summarized-thinking extraction, because the model's capabilities in those areas introduce real misuse risk. Anthropic also does not support Zero Data Retention because some misuse patterns only become visible across cumulative requests.
Prompts and completions are retained for 30 days and are not used to train Claude. To use Fable 5, set model to in the . anthropic/claude-fable-5AI SDKAI 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 , , , and more. AI Gateway reflects provider pricing with no markup and does not charge a platform fee on inference, including on (BYOK) requests.
custom reportingZero Data Retention supportdynamic provider sorting by latency and costBring Your Own KeyLearn more about , view the or try it in our . AI GatewayAI Gateway model leaderboardmodel playgroundRead more
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