Claude Fable 5Latest
Next-generation intelligence for long-running agents
- Context window
- 1Mtokens
- Max output
- 128Ktokens
- Input pricing
- $10/ MTok
- Output pricing
- $50/ MTok
Overview
Claude Fable 5 is Anthropic's most capable widely released model, built for the most demanding reasoning and long-horizon agentic work. Claude Mythos 5 shares the same capabilities and is available only in limited release through Project Glasswing.
The headline change for integrations: Claude Fable 5 includes safety classifiers that can decline requests. Claude Mythos 5 does not include these classifiers. If your integration calls Claude Fable 5, plan for three changes: new response handling for refusals, fallback options for retrying on another Claude model, and new billing rules. Refusals, fallback, and billing on Claude Fable 5 summarizes all three.
Fable vs. Mythos
Claude Mythos 5 is offered separately, by invitation only, for defensive cybersecurity workflows as part of Project Glasswing. It shares Claude Fable 5's specifications and pricing; Claude Fable 5 includes safety classifiers that can decline requests, and Claude Mythos 5 does not. For access, contact your Anthropic, AWS, or Google Cloud account team.
How it compares
| Model | Context | Max output | Price / MTok | Latency | Thinking | Default effort | Knowledge cutoff |
|---|---|---|---|---|---|---|---|
| Claude Fable 5This model | 1M | 128K | $10 / $50 | Slower | Adaptive (always on) | high | Jan 2026 |
| Claude Opus 5 | 1M | 128K | $5 / $25 | Moderate | Adaptive | high | May 2026 |
| Claude Sonnet 5 | 1M | 128K | $2 / $10 | Fast | Adaptive | high | Jan 2026 |
| Claude Haiku 4.5 | 200K | 64K | $1 / $5 | Fastest | Extended | — | Feb 2025 |
Specifications
Model IDs
- Claude API
Pricing
- Input
- $10 / MTok
- Output
- $50 / MTok
- 5m cache write
- $12.50 / MTok
- 1h cache write
- $20 / MTok
- Cache read
- $1 / MTok
- Batch API
- 50% discount on input and output
- Full price list
- Pricing
Capabilities
- Context window
- 1M tokens
- Max output
- 128K tokens
- Thinking
- Adaptive (always on)
- Default effort
high- Comparative latency
- Slower
- Input → output
- Text and images → text
- Reliable knowledge cutoff
- Jan 2026
- Training data cutoff
- Jan 2026
Availability
- Status
- Active (latest)
- Released
- June 9, 2026
- Retirement
- Not sooner than June 9, 2027
- Platforms
- Claude APIAmazon BedrockGoogle CloudMicrosoft FoundryClaude Platform on AWS
Resources
Model-specific prompting guidance for long-horizon and agentic work.
Handle classifier refusals and retry on another Claude model with the fallbacks parameter.
The only thinking mode on Claude Fable 5. Steer depth with effort.
Reference
The system prompt Claude Fable 5 uses on claude.ai and the Claude apps.
Safety evaluations and deployment decisions for Claude Fable 5 and Claude Mythos 5.
Full price list, including batch discounts and prompt caching rates.
How model IDs, aliases, and pinned snapshots work.
Lifecycle status and retirement commitments for every Claude model.
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