Cosine AI
Revolutionize software development with seamless automation, deep code understanding, and comprehensive impact assessments, empowering developers to focus on innovation.. [Contact for Pricing]
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What is Cosine AI?
Cosine AI is a fully agentic AI software engineer that handles entire engineering tasks autonomously, from fixing bugs and building features to refactoring code and updating documentation. Unlike traditional AI coding assistants, Cosine operates asynchronously as a true teammate that can work on multiple tickets simultaneously without constant human oversight. It connects directly to your codebase and ticketing systems like GitHub, Jira, and Linear, analyzing repositories and opening pull requests for review.
The platform runs on proprietary models called Genie and Lumen, which are trained on real production code and optimized for maintainable software. Key features include autonomous operation across desktop, cloud, and terminal (CLI); multi-agent orchestration; CI workflow monitoring with automated iteration when tests fail; Vercel integration for frontend previews; and support for both mainstream and niche enterprise languages including C, R, Matlab, Fortran, Verilog, and Rust. The Chat feature provides contextual codebase insights through natural language queries.
Cosine is designed for software engineers, development teams, and engineering organizations that want to offload routine coding tasks and ship faster. It suits individuals working on side projects, teams collaborating on codebases, and enterprises requiring strict security controls with options for public cloud, dedicated single-tenant, or fully air-gapped deployments. The tool is particularly valuable for handling legacy code, complex bug fixes, and end-to-end feature development.
Cosine AI pricing
Pricing model: Freemium
Cosine offers a Free Plan with 80 tasks included on signup (no credit card required), giving full access to all capabilities. After using the 80 free tasks, users can upgrade to paid plans: Hobby Plan provides 80 monthly tasks and 10 projects, ideal for individuals and hobbyists; Professional Plan provides 240 monthly tasks and 100 projects, designed for teams building together, priced at $99/month. Enterprise deployment options include Public Cloud (fully managed, fastest adoption), Dedicated Tenant (managed single-tenant with enterprise controls and private data boundaries), and Air-Gapped (fully inside your infrastructure with no external dependencies, option for post-training/fine-tuning on internal codebases).
Cosine AI pros
- Fully autonomous operation - assign tasks and come back later without micromanaging
- Works asynchronously across CLI, desktop, and cloud with seamless handoff
- Handles multiple tickets simultaneously in parallel
- Top benchmark performer - 53.9% on Niche-Bench, beating GPT-5 and Gemini
- Integrates natively with GitHub, Jira, Linear, Slack, and Vercel
- Supports niche enterprise languages: C, R, Matlab, Fortran, Verilog, Rust
- Excellent at fixing bugs in unfamiliar or messy legacy codebases
- Writes end-to-end features from backend routes to React components
- CI workflow monitoring with automated iteration until tests pass
- Vercel integration provides frontend previews in browser without local pull
- Chat feature provides architectural insights and codebase answers in natural language
- Multi-agent capability for complex task orchestration
- Enterprise deployment options including air-gapped for strict security
- Trained to avoid code slop - minimal diffs matching your codebase style
- 80 free tasks on signup with no credit card required
- File reading, search, keyword search, and directory navigation tools
- Code execution capability to test functionality and validate changes
Cosine AI cons
- Windows requires workaround via Windows Subsystem for Linux for CLI
- Task-based pricing may become expensive for heavy usage beyond plan limits
- Learning curve for prompting effectively like a human engineer
- Requires codebase cloning and indexing which takes initial setup time
- Still needs human review of pull requests before merging
- May struggle with extremely specialized domain knowledge without context
- Free tier limited to 80 tasks total (not recurring monthly)
- Hobby plan only 80 monthly tasks may be too low for active developers
Frequently asked questions about Cosine AI
What is Cosine AI?
Cosine is a fully agentic AI software engineer that acts like a true team member. It can take on entire engineering tasks—from understanding legacy code to writing features, fixing bugs, updating documentation, and running tests. It's fully asynchronous and agentic, meaning you can assign it multiple tasks and come back later to review results without micromanaging. Cosine runs on proprietary models called Genie and Lumen trained on real production code.
How do I get started with Cosine?
You can get started by importing from GitHub (connect your account and choose a repo), pasting a URL for public repos, using curated templates for common app types, or using the 'Need some inspiration?' tab for mini-project ideas. Once imported, Cosine automatically indexes your code to reason about structure, dependencies, and logic. You can then add tasks to your project and assign them to Cosine.
What integrations does Cosine support?
Cosine integrates with GitHub (turn issues into tasks, opens real PRs), Jira and Linear (tag an issue and Cosine picks it up), Slack (assign tasks directly from chat with @cosine), and Vercel (automatically track deployments for UI changes). You connect integrations via the 'Integrations' tab in the menu bar, selecting and enabling the tool you want.
Can Cosine work with legacy code?
Yes, Cosine is particularly good at working in legacy systems. The Genie model is trained on real-world, lived-in codebases, not just greenfield projects. It handles messy or unfamiliar codebases with grace, making it effective for fixing bugs in legacy systems and refactoring gnarly logic.
How does Cosine handle CI/CD workflows?
Cosine can monitor and interact with CI workflows through Workflow Monitoring. You configure it to watch specific CI steps like tests or linters in project settings. If a workflow step fails, Cosine performs Automated Iteration by analyzing logs, making necessary code changes, and re-running the workflow until it passes.
What programming languages does Cosine support?
Cosine supports mainstream programming languages and is post-trained for enterprise and niche languages including C, R, Matlab, Fortran, Verilog, and Rust. The 8-step data pipeline turns real production code into verifiable training trajectories, enabling work across diverse language ecosystems.
Can I use Cosine on Windows?
Cosine currently supports MacOS and Linux natively for the CLI. For Windows users, there is a workaround: use Windows Subsystem for Linux (WSL) and download Ubuntu, then follow the instructions from the docs page to install and use Cosine CLI.
What is the Lumen model?
Lumen is Cosine's family of production-first coding models built for real engineering work: maintainable software, long-lived systems, and complex codebases most models struggle with. It's trained to avoid duplication, dead code, and unnecessary complexity, optimized for minimal diffs that match your codebase's style. Lumen achieved 53.9% on Niche-Bench, outperforming GPT-5.5, Gemini 3.1 Pro, and other models.
How does the Chat feature work?
Chat is the cornerstone of interaction within Cosine, designed to comprehend and engage with your codebase in natural language. It offers contextual insights like a domain-specific ChatGPT. You can ask architectural questions ('What patterns does this codebase use?'), technology stack questions, or granular inquiries ('Where do we handle token expiration?'). Chat also proactively suggests enhancements aligned with your coding conventions.
What enterprise deployment options are available?
Cosine offers three enterprise deployment options: Public Cloud (fully managed, fastest adoption with standard cloud controls), Dedicated Tenant (managed single-tenant cloud with private environment and enterprise isolation for private data boundaries), and Air-Gapped (fully inside your infrastructure with no external dependencies or data egress, for strict isolation/regulatory/classified-network requirements, with option to post-train or fine-tune on internal codebases).