Claude Fable 5 (batch)

Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding. It supports text, image, and file inputs with text output, with reasoning support and a 1M-token context window. It is suited for long-running, complex, and asynchronous tasks that previously required frequent human check-ins. It is particularly strong at end-to-end work that would otherwise take a person hours, days, or weeks - taking on problems that are long-running, ambiguous, or highly multi-step. It executes well-scoped tasks with few mistakes, automatically self-correcting through verification loops, and ships with robust safeguards.

ChatAnthropic1M tokens$5.4503 / $27.2515 · 1M

anthropic/claude-fable-5:batch

Context
1M tokens
Completion cap
128,000
Tools
Yes
JSON
Yes
Released
2026-06-09

Call it from Geek Hub

Same OpenAI SDK. Change the base URL and the model id.

curl https://api.geekhub.mx/v1/chat/completions \
  -H "Authorization: Bearer $GEEKHUB_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "anthropic/claude-fable-5:batch",
    "messages": [{"role": "user", "content": "Hola"}]
  }'
Get an API key

Frequently asked questions

What is Claude Fable 5 (batch)?
Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding. It supports text, image, and file inputs with text output, with reasoning support and a 1M-token context window. It is suited for long-running, complex, and asynchronous tasks that previously required frequent human check-ins. It is particularly strong at end-to-end work that would otherwise take a person hours, days, or weeks - taking on problems that are long-running, ambiguous, or highly multi-step. It executes well-scoped tasks with few mistakes, automatically self-correcting through verification loops, and ships with robust safeguards. Claude Fable 5 (batch) runs on the Geek Hub API (OpenAI-compatible). Model id: anthropic/claude-fable-5:batch.
Is Claude Fable 5 (batch) free?
No. Input is $5.4503 per 1M tokens and output is $27.2515 per 1M tokens on Geek Hub (markup included).
What is the context length of Claude Fable 5 (batch)?
Claude Fable 5 (batch) has a 1M tokens context window. It supports up to 128,000 completion tokens.
Does Claude Fable 5 (batch) support tool calling and structured outputs?
Claude Fable 5 (batch) accepts tools and tool_choice for function calling. It also supports structured outputs via a JSON schema in response_format.
When was Claude Fable 5 (batch) released?
Claude Fable 5 (batch) was released on 2026-06-09.

More models from Anthropic