Model detail
claude-fable-5-1
Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual code generation, and finance and analysis tasks in particular. It also tends to be more concise than Fable 5 in its plans and summaries. We recommend testing it as a direct upgrade wherever you use Fable 5 today, and alongside Opus 5 on reasoning-heavy tasks.
Model specs
- Context length
- 1M
- Max output
- 128K
- I/O modalities
- Text / Image
- Released
- 2026-09
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API endpoints
One MixRoute gateway, OpenAI-compatible
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Anthropic Messages
/v1/messagesPOST -
OpenAI-compatible
/v1/chat/completionsPOST
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Pricing
Flat rate, unit: /1M Tokens
Input
$10.0000 /1M Tokens
Completion
$50.0000 /1M Tokens
Cache read
$0.2500 /1M Tokens
Cache creation
$12.5000 /1M Tokens
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Selection summary
Quickly judge whether it fits your workload
What is this model good for?
Agentic coding, long-running workflows, and knowledge work
Use Claude Fable 5.1 for long code refactors, front-end and visual code generation, and finance and analysis tasks. It improves on Fable 5 with gains in agentic coding and knowledge work, and is more concise in plans and summaries.
What should you check before using it?
Test as a direct upgrade from Fable 5
Fable 5.1 is recommended as a direct upgrade wherever you use Fable 5. Also test alongside Opus 5 on reasoning-heavy tasks to find the best fit for your workload.
Why use it through MixRoute?
Use the compatible endpoint with stable model ID
Use the confirmed compatible endpoint with model ID claude-fable-5-1 through MixRoute.
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Token cost estimator
Live estimate from this page's pricing, not an actual bill
Share of the same prefix read repeatedly, up to 100%
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FAQ
Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work. It is particularly strong at long code refactors, front-end and visual code generation, and finance and analysis tasks.
One endpoint, a testable decision
Test this model and alternate routes with the same request format
Start from a real workload, then let quality, total cost, and failure conditions decide whether to send production traffic.