Fable 5.5
According to community reports, Fable 5.5 is a large language model in a limited shadow-testing phase, with a small subset of users quietly routed to experience it. The identity of its developer has not been officially confirmed.
Core Facts
Timeline (last 90 days)
Obsidian 3, a model suspected to be Fable 5.5, scored 46.8% on the Frontier Code 2.0 benchmark at high reasoning intensity, only narrowly leading Opus 5.5's 45.5%.
Beta feedback on Fable 5.5 centers on its broad capabilities and its grasp of intent and taste, but reproducible evaluation data is currently lacking.
Fable 5.5 is about to be released, and beta users are already using it.
In SVG animation generation, Gemini 4 Argon outperforms the GPT series, but has been clearly surpassed by Fable 5.5.
Anthropic may release Claude Fable 5.5 earlier than expected; the model was discovered through an automated TrueFoundry model listing, and related entries were found on Microsoft Azure infrastructure, suggesting it may already be deployed behind the scenes.
A post appeared in the Reddit community titled "Fable 5.5 should be released any moment", with an accompanying image showing a list purportedly from the Azure model catalog, in which the words "Claude Fable 5.5" appear with a status marked as Generally Available.
Data related to Fable 5.5 has appeared in LiteLLM's model_prices_and_context_window_backup.json file, indicating that the model already has callable conditions at the API level, with pricing and context window parameters determined.
HuggingNews reported that Microsoft Azure lists Claude Fable 5.5 as generally available (GA).
Fable 5.5's specific capability improvements, pricing strategy, and competitive benchmarking have not yet been officially confirmed.
Someone used Fable 5.5 to generate a playable first-person 3D SWAT shooter game in a single attempt using three.js, complete with gun feel, ragdoll physics, and enemy NPC intelligent behavior.
8 more timeline events
All Facts (6)
Anthropic released Opus 5.5 at the same point in time.
65%UnverifiedObsidian 3, a model suspected to be Fable 5.5, scored 46.8% on the Frontier Code 2.0 benchmark at high reasoning intensity, only narrowly leading Opus 5.5's 45.5%.
50%UnverifiedBeta feedback on Fable 5.5 centers on its broad capabilities and its grasp of intent and taste, but reproducible evaluation data is currently lacking.
50%UnverifiedSomeone used Fable 5.5 to generate a playable first-person 3D SWAT shooter game in a single attempt using three.js, complete with gun feel, ragdoll physics, and enemy NPC intelligent behavior.
50%UnverifiedFable 5.5 is about to be released, and beta users are already using it.
50%UnverifiedAnthropic's next-generation frontier model Claude Fable 5.2 is reportedly ready and is regarded as a significant upgrade over Fable 5.1.
50%