Claude Fable 5.2
5.0 out of 5 starsSWE-2
5.0 out of 5 starsAverage Ratings 1 Rating
Average Ratings 1 Rating
Description
Claude Fable 5.2 is a frontier artificial intelligence model developed by Anthropic for advanced reasoning, autonomous software development, scientific discovery, and complex professional workflows. The model improves on Claude Fable 5.1 with stronger performance in programming, visual analysis, mathematical problem-solving, and agent-driven task execution. Its software engineering capabilities support large-scale codebase analysis, feature implementation, debugging, performance optimization, automated testing, and complex software migrations. Claude Fable 5.2 can coordinate multiple AI agents to complete long-running engineering projects and delegate simpler operations to smaller language models. The model also supports scientific research, hardware design, robotics-related reasoning, data analysis, and technical investigations that require iterative experimentation and evaluation. Configurable reasoning effort allows developers to balance computational cost, response time, and problem-solving depth according to task requirements. Anthropic reports a 49.1% score on FrontierCode 2.0, 69.9% on FrontierSWE v2, and 74.2% on Humanity's Last Exam with tools. Claude Fable 5.2 generates output up to 30% faster than its predecessor and offers an optional fast mode with up to 2.5 times faster generation, alongside safeguards for high-risk cybersecurity and biological research. The model is available through Claude applications, Claude Code, Anthropic's API, Amazon Web Services, Google Cloud, and Microsoft Azure, with standard API pricing of $8 per million input tokens and $40 per million output tokens.
Description
SWE-2 is a software engineering model from Cognition built for agentic coding tasks that require strong performance at lower computational and monetary cost. It is post-trained from the Kimi K3 base model and extends Cognition’s earlier SWE-1.7 training approach with a new reinforcement learning method for jointly optimizing multiple reasoning-effort settings. Medium, high, and maximum effort modes provide different tradeoffs between speed, cost, exploration, and verification depending on task complexity. The model is trained to inspect only the parts of a codebase that are likely to matter, helping it reach implementation faster and reduce unnecessary exploration. SWE-2 can generate and modify code, run tests, analyze repositories, work through terminal tasks, and verify whether implementations satisfy user requirements. Cognition also reports improvements in end-to-end test creation, regression detection, instruction following, and re-deriving conclusions when challenged. Its training process incorporates cost-aware rewards, length-weighted reward baselines, expanded reinforcement learning environments, and hardened verifiers intended to improve both efficiency and reliability. SWE-2 is positioned as a cost-efficient alternative to larger frontier coding models while remaining competitive on software engineering benchmarks such as FrontierCode, DeepSWE, and Terminal-Bench. The model is available in Devin Desktop and Devin CLI and is being introduced to additional Cognition products including Devin Web and Fusion.
API Access
Has API
Yes
API Access
Has API
No
Integrations
.NET
Yes
C#
Yes
C++
Yes
Devin
Yes
Devin Desktop
Yes
HTML
Yes
Kotlin
Yes
Kubernetes
Yes
Objective-C
Yes
PHP
Yes
Integrations
.NET
Yes
C#
Yes
C++
Yes
Devin
Yes
Devin Desktop
Yes
HTML
Yes
Kotlin
Yes
Kubernetes
Yes
Objective-C
Yes
PHP
Yes
Pricing Details
$8 per 1M tokens (input)
$8 per million input tokens and $40 per million output tokens
Free Trial
No
Free Version
No
Pricing Details
$20/month
Free Trial
No
Free Version
Yes
Deployment
Web-Based
Yes
On-Premises
No
iPhone App
No
iPad App
No
Android App
No
Windows
No
Mac
No
Linux
No
Chromebook
No
Deployment
Web-Based
Yes
On-Premises
No
iPhone App
No
iPad App
No
Android App
No
Windows
No
Mac
No
Linux
No
Chromebook
No
Customer Support
Business Hours
No
Live Rep (24/7)
No
Online Support
Yes
Customer Support
Business Hours
No
Live Rep (24/7)
No
Online Support
Yes
Types of Training
Training Docs
Yes
Webinars
No
Live Training (Online)
No
In Person
No
Types of Training
Training Docs
Yes
Webinars
No
Live Training (Online)
No
In Person
No
Vendor Details
Company Name
Anthropic
Founded
2021
Country
United States
Website
claude.ai
Vendor Details
Company Name
Cognition
Founded
2023
Country
United States
Website
cognition.com