Claude Fable 5

claude-fable-5

Claude Fable 5 is presented as a Mythos-level Claude model for ambitious, long-running projects. Source pages emphasize autonomous knowledge work, software engineering, vision, memory, and the ability to work for extended periods with sub-agents. Its description should feel more like a project-level collaborator than a short-turn assistant.

Context Window

1M tokens

Maximum Output

128K tokens

Release Date

Jun 9, 2026

Modalities

Claude Fable 5 Pricing

Input PriceOutput PriceCache Read
$10/M$50/M$1/M

Claude Fable 5 API Capabilities

Reasoning

Supported

Tool calling

Supported

Temperature parameter

Not supported

Attachments

Supported

Knowledge Base

2026-01-31

Endpoint Protocols

Completions APIMessages API

Claude Fable 5 Model Highlights

Claude Fable 5 combines long-horizon autonomy, software engineering, visual understanding and complex knowledge work for demanding development tasks.

Long-Horizon Autonomy

Maintains focus across extended, complex tasks and can use its own notes to improve later decisions.

Large-Scale Engineering

Handles difficult production coding work and codebase-wide changes with fewer intervention points.

Visual Analytical Understanding

Interprets detailed figures, charts and screenshots while connecting visual evidence to technical reasoning.

Claude Fable 5 Use Cases

Claude Fable 5 is suited to large codebase changes, extended analytical research and demanding vision-based reconstruction tasks.

Codebase-Wide Migration

Analyze dependencies across a large repository, implement coordinated changes and validate the resulting migration.

Extended Analytical Research

Investigate complex evidence over many steps, retain intermediate findings and produce a reasoned synthesis.

Screenshot-to-Application Reconstruction

Read interface screenshots, infer structure and behavior, and generate a working implementation that matches the visual reference.

How to Use Claude Fable 5 via the TokenHub API

Create API key
import OpenAI from "openai"

const client = new OpenAI({
  apiKey: process.env.TOKENHUB_API_KEY,
  baseURL: "https://us-api.tokenhub.com/v1",
})

const result = await client.chat.completions.create({})
console.log(result.choices[0]?.message?.content)

Claude Fable 5 Benchmarks

Claude Fable 5 (Adaptive Reasoning, Max Effort, Opus 4.8 Fallback)

Index score
Artificial Analysis Intelligence IndexArtificial Analysis broad capability aggregate59.9
Artificial Analysis Coding IndexArtificial Analysis software task aggregate62
Knowledge & Reasoning
GPQAAdvanced science problem solving92.6%
HLEBroad expert-level exam set53.3%
Coding & Engineering
SciCodeScientific coding challenges60.2%
Terminal-Bench HardHard terminal task execution62.9%
Instruction Following & Agent Tasks
IFBenchPrompt constraint adherence63.5%
AA-LCRLong-context reasoning70%
τ²-BenchAgent workflow tasks98.5%

Metrics sourced from Artificial Analysis

Claude Fable 5 Comparisons

Kimi K3VSClaude Fable 5

Kimi K3 vs Claude Fable 5 model comparison reviews pricing, context limits, output tokens, modalities, benchmarks, and API fit for production AI apps.

Claude Opus 5VSClaude Fable 5

Claude Opus 5 vs Claude Fable 5 model comparison reviews pricing, context limits, output tokens, modalities, benchmarks, and API fit for production AI apps.

Claude Sonnet 5VSClaude Fable 5

Claude Sonnet 5 vs Claude Fable 5 model comparison reviews pricing, context limits, output tokens, modalities, benchmarks, and API fit for production AI apps.

Claude Fable 5 Guides & Articles

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Frequently asked questions about Claude Fable 5

Understand what Claude Fable 5 is, its best uses, distinguishing strengths, practical tradeoffs, and safe TokenHub integration guidance.

What is Claude Fable 5, and where does it fit in Anthropic’s model lineup?+

Claude Fable 5 is Anthropic’s highest-capability Claude tier for demanding reasoning and autonomous work. Its public availability has changed, so confirm current access and data-handling conditions before deployment.

Which workloads are the best fit for Claude Fable 5?+

Best-fit scenarios include long-horizon autonomous agents, complex multi-step reasoning, and professional document and decision analysis. Test representative inputs and define measurable acceptance criteria before production.

Why might a team select Claude Fable 5 over a smaller or older model?+

Key strengths include adaptive allocation of reasoning effort, strong autonomy on extended tasks, and effective use of tools and function calls. This combination is especially useful for complex multi-step reasoning.

What should be validated before relying on Claude Fable 5?+

Consider another model when stable, broadly available production access is mandatory, the workload is highly cost-sensitive, or the workflow cannot include human review for important decisions. Verify important factual, legal, financial, medical, or operational outputs with qualified human review.

What is the practical TokenHub setup guidance for Claude Fable 5?+

In TokenHub, select the exact model identifier displayed for Claude Fable 5, use the endpoint documented for your account, and authenticate with your TokenHub credentials. Because provider access conditions have changed, verify current TokenHub availability and any data-retention requirements before sending sensitive data.

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