Cognition's Devin Integrates Claude Fable 5, Leads Real-World Engineering Benchmark

Cognition

Jun 10, 2026 · Updated Jun 20, 2026

Cognition has made Anthropic's Claude Fable 5 model available within its Devin AI software engineer across Cloud, Desktop, and CLI. This integration positions Fable 5 as the top performer on Cognition's FrontierCode benchmark, highlighting its advanced capabilities for production-grade code quality and mergeability in autonomous engineering tasks.

Cognition has integrated Anthropic's Claude Fable 5 model into its Devin AI software engineer, available across Devin Cloud, Desktop, and CLI. This model excels at long-horizon reasoning, debugging, and generalizing to unfamiliar tools, including MCP integrations and Computer Use.

FrontierCode Main Score (Claude Fable 5): 46.3%
Devin Ultra Agent Cost: ~40% more than default
Fable 5 Availability: Devin Cloud, Desktop, CLI
FrontierCode Evaluation Criteria: Quality, Mergeability
Fable 5 Capabilities: Long-horizon reasoning, debugging, unfamiliar tool generalization (MCP, computer use)

Following Anthropic's launch of Claude Fable 5 and its adoption by other AI coding tools like Cursor, the model now holds the #1 spot on Cognition's FrontierCode benchmark. This benchmark evaluates AI models on real-world engineering tasks, grading code quality and mergeability, confirming its production readiness.

Devin Cloud's Ultra agent now offers Claude Fable 5, tuned to cost approximately 40% more than the default Devin agent. The model is also accessible in Devin Desktop and CLI, enabling autonomous software development with advanced reasoning and debugging for complex tasks.

View the full update on devin.ai

Cognition

@cognitionJun 9

Claude Fable 5 is now available in Devin. Fable 5 earns the #1 spot on FrontierCode, our benchmark for real-world engineering tasks that grades mergeability and quality:

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