Claude Fable 5
Claude Fable 5 is Anthropic's June 2026 public model and remains served separately from its newer Fable 5.1 successor, released in September 2026.
Platform: Replicate
Reasoning AICoding AssistantAutonomous WorkflowsSafety-aware AI
Input: $10 per million tokens; Output: $50 per million tokens
Commercial🚀Function Overview
A high-capability language model for long-form coding, complex analysis, and long-horizon tasks with practical safety fallback behavior.
Key Features
- Large context and high output support for extended coding and agent tasks
- Safety-aware classification and refusal behavior with escalation behavior for uncertain outputs
- Mythos-class capabilities under a release-safe, generally available posture
- Multimodal input support for vision-assisted coding and review tasks
- Use-case fit for long-horizon and planning-heavy AI workflows
Use Cases
- •Complex coding and software engineering assistance
- •Long-horizon agentic workflows
- •Document-heavy analysis and iterative reasoning tasks
- •Vision-aware explanation and code-review prompts
- •Production-facing copilots where safety boundaries matter
⚙️Input Parameters
prompt
stringThe prompt to send to the model
image
stringOptional input image; priced by image token rules
system_prompt
stringSystem prompt for role and policy controls
max_tokens
integerMaximum number of output tokens to generate
effort
stringControls reasoning effort for adaptive, high-depth tasks
max_image_resolution
numberMaximum image resolution in megapixels; reduces token/cost and latency impact
💡Usage Examples
Example 1
Input Parameters
{
"prompt": "Compare three options for refactoring a legacy API layer and propose the safest rollout plan.",
"system_prompt": "You are a reliable software architect. Prioritize safety and backward compatibility.",
"effort": "high",
"max_tokens": 4096,
"max_image_resolution": 0.5
}Output Results
I would evaluate the three options by balancing blast radius, rollback path, and production risk.
First, I would classify the change set by coupling level and user impact.
Then I would apply a staged rollout: smoke tests, contract tests, canary deployment, and monitoring gates.
Option A offers speed but the highest breaking-risk; Option B reduces regression risk with moderate engineering effort; Option C is safest but slower.
Recommended rollout order: Option B with explicit rollback scripts and a compatibility smoke check at each step.
Quick Actions
Technical Specifications
- Hardware Type
- Commercial Use
- Supported
- Pricing
- Input: $10 per million tokens; Output: $50 per million tokens
- Platform
- Replicate