MiscSubjects

Anthropic: Claude Fable 5

Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding.

AnthropicClaude Fable 5
anthropic/claude-fable-5
2026-06-09text+image+file->textreasoning: max / xhigh / high / medium / low
Coding index
76.5
Artificial Analysis
Agentic index
50.7
Artificial Analysis
Design Arena
1254 Elo · #1
agentichtmlslides · 59.4% wins
Input
$10
per 1M tokens
Output
$50
per 1M tokens
Cached input
$1
per 1M tokens
Context
1M
tokens it reads
Max output
128K
tokens it writes
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...
inspect — the catalog entry
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  "supported_voices": null,
  "knowledge_cutoff": null,
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  "links": {
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        "category": "uicomponent",
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}
References (1)
  1. Stored model catalog — Nov 6, 2026
Via
OpenRouter
Id
openrouter/anthropic/claude-fable-5
Model id
anthropic/claude-fable-5
Name
Anthropic: Claude Fable 5
Description
Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding.
Family
anthropic
Canonical slug
anthropic/claude-5-fable-20260609
Price in
10
Price out
50
Price cache read
1
Price cache write
12.5
Price cache write 1h
20
Price web search
10000
Price overrides
[]
Context
1000000
Max completion tokens
128000
Modality
text+image+file->text
Input modalities
["text","image","file"]
Output modalities
["text"]
Tokenizer
Claude
Knowledge cutoff
null
Created
1781007515
Moderated
true
Params
["include_reasoning","max_completion_tokens","max_tokens","reasoning","reasoning_effort","response_format","stop","structured_outputs","tool_choice","tools","verbosity"]
Default parameters
{"temperature":null,"top_p":null,"top_k":null,"frequency_penalty":null,"presence_penalty":null,"repetition_penalty":null}
Tools
true
Reasoning
true
Reasoning efforts
["max","xhigh","high","medium","low"]
Reasoning default effort
high
Reasoning mandatory
true
Reasoning default enabled
null
Vision
true
Expiration date
null
Page dataOpen JSON
page.json
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  "hero": "",
  "facts": {
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  "sources": [
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