# Claude Fable 5.1

Anthropic's updated frontier model improving across the board on agentic coding, long-running agent workflows, and knowledge work. More concise in plans and summaries than Fable 5.

## Overview

- **Provider:** Anthropic
- **Model ID:** `claude-fable-5-1`
- **Type:** Chat
- **Canonical URL:** https://modelstack.cc/models/chat/claude-fable-5-1
- **Version:** Fable 5.1
- **Best for:** Frontier reasoning, long code refactors, front-end and visual code generation, agentic coding, finance and analysis

## Pricing

| Usage | Price |
| --- | ---: |
| Input | $10 / 1M tokens |
| Output | $50 / 1M tokens |
| Cache read | $0.25 / 1M tokens |
| Cache write (5 minutes) | $12.5 / 1M tokens |
| Cache write (1 hour) | $20 / 1M tokens |

## Specifications

- **Context window:** 1M
- **Maximum output:** 128K
- **Typical latency:** 22 ms
- **Released:** 2026-09-01

## Capabilities

- chat
- tool_use
- reasoning
- vision
- coding
- analysis
- long_context

## API usage

Use this model ID in a ModelStack API request:

```json
{
  "model": "claude-fable-5-1"
}
```

For the rendered page, visit https://modelstack.cc/models/chat/claude-fable-5-1.