Claude Fable 5.1
Claude Fable 5.1 is an Anthropic model for demanding reasoning and long-horizon agentic work, with a one-million-token context window and up to 128K output tokens.
Overview
The model accepts text and images and returns text. Anthropic lists it as active and available through the Claude API and supported partner platforms.
Model specifications
- Family
- Claude 5.1
- Context
- 1,000,000 tokens
- Input
- Text, Image
- Output
- Text
- Open weights
- No
- Capabilities
- Reasoning, Vision, Tool Use
Related entities
Amp
Amp is a coding agent from Amp Frontier Corporation that runs in the terminal, on the web, in cloud orbs, and through desktop and mobile apps, with integrations for common code editors.
Anthropic
Anthropic is an AI research and product company that develops Claude models, the Claude API, and products including Claude Code.
Claude Code
Claude Code is Anthropic's coding agent for working directly with a codebase from the terminal, supported IDEs, the web, GitHub, Slack, and other product surfaces.
Cursor
Cursor is a code editor from Anysphere with code completion and agents that can inspect repositories, edit files, run terminal commands, and work from desktop, terminal, or web surfaces.
Devin CLI
Devin CLI is Cognition's local coding agent for terminal workflows. It can work with multiple model providers, run against a local repository, and hand sessions off to Devin Cloud.
Devin Desktop
Devin Desktop is Cognition's desktop coding environment, renamed from Windsurf, with an integrated IDE and controls for running and reviewing local and cloud coding agents.