# Kosuke: what it does, who it is for and alternatives > Kosuke: AI agent (Sensei) that runs each website or app change in its own branch and sandbox, then brings back a prototype, a recording and a verdict for… Source: https://learn.ynteractive.com/content/ai-tools/tool/kosuke · Updated 2026-10-20 · Free from Stepthrough (https://learn.ynteractive.com) Updated October 20, 2026 · By [Robert Breen](https://learn.ynteractive.com/content/about) AI agent (Sensei) that runs each website or app change in its own branch and sandbox, then brings back a prototype, a recording and a verdict for you to judge. It works with your own coding agent, such as Claude Code. [Coding & developer](https://learn.ynteractive.com/content/ai-tools/coding-developer) · Paid · Free lesson Official site: [kosuke.ai](https://kosuke.ai) ## What Kosuke does You describe a change in plain language, and Kosuke's Sensei agent plans it, builds it, has Claude and GPT review it, and then tests it in your running app. You get one notification when the change is ready, and it arrives as a pull request you can merge or send back. Every plan needs your own coding agent subscription, such as Claude Code or Codex. ## Who Kosuke is for - Product managers - Founders - Software developers - Agency owners ## Key features - Each change gets its own branch, sandbox and live preview - Choose the coding agent, such as Claude Code - Two model labs (Claude and GPT) review each change - QA runs in your running app and is recorded - Changes arrive as pull requests to merge or send back ## Privacy and data Kosuke says it does not train on customer code or agent transcripts, uses TLS 1.2+ in transit and AES-256 at rest, and isolates sandboxes per change; a SOC 2 Type I audit is in progress. Source: [Kosuke’s own page](https://kosuke.ai/security). Before you put client data in, check your company’s AI rules and the plan’s data settings. ## Learn Kosuke free on Stepthrough - Free lesson: [Kosuke: Let the AI Test Its Own Changes with Automated QA](https://learn.ynteractive.com/content/kosuke-automated-qa-test-ai-changes) (12 min) - Comparison: [The best AI tools for product managers in 2026](https://learn.ynteractive.com/content/compare/best-ai-tools-for-product-managers) - Comparison: [The best AI tools for project managers in 2026](https://learn.ynteractive.com/content/compare/best-ai-tools-for-project-managers) - Glossary: [Git branch](https://learn.ynteractive.com/content/glossary/git-branch) - Glossary: [Preview deployment](https://learn.ynteractive.com/content/glossary/preview-deployment) - Glossary: [Pull request (PR)](https://learn.ynteractive.com/content/glossary/pull-request) - Glossary: [Sandbox environment](https://learn.ynteractive.com/content/glossary/sandbox-environment) ## Alternatives to Kosuke Other AI coding tools in the directory. - [**Claude Code**](https://learn.ynteractive.com/content/ai-tools/tool/claude-code) Paid Anthropic’s coding agent that works in your terminal and editor to build, fix and explain code. - [**Webhook.site**](https://learn.ynteractive.com/content/ai-tools/tool/webhook-site) Free plan Get a test URL that shows every webhook request sent to it. The easiest way to see what an app sends. - [**Litescrape**](https://learn.ynteractive.com/content/ai-tools/tool/litescrape) Free trial A low-cost search and scraping API you can call from n8n and other automations. - [**GitHub Copilot**](https://learn.ynteractive.com/content/ai-tools/tool/github-copilot) Free plan An AI pair programmer in your editor that suggests code, explains it and fixes bugs. - [**Cursor**](https://learn.ynteractive.com/content/ai-tools/tool/cursor) Free plan An AI code editor that writes and edits code across your whole project from chat. - [**Replit**](https://learn.ynteractive.com/content/ai-tools/tool/replit) Free plan Build and host apps in the browser, with an AI agent that writes the code from a description. [All 22 AI coding tools](https://learn.ynteractive.com/content/ai-tools/coding-developer) ## Frequently asked questions **What is Kosuke?** AI agent (Sensei) that runs each website or app change in its own branch and sandbox, then brings back a prototype, a recording and a verdict for you to judge. It works with your own coding agent, such as Claude Code. You describe a change in plain language, and Kosuke's Sensei agent plans it, builds it, has Claude and GPT review it, and then tests it in your running app. You get one notification when the change is ready, and it arrives as a pull request you can merge or send back. Every plan needs your own coding agent subscription, such as Claude Code or Codex. **Who is Kosuke for?** Kosuke fits product managers, founders, software developers and agency owners, and other office teams with the same job to do. **Is Kosuke free?** Kosuke is a paid tool. Plans change often, so check the official pricing page before you commit. **What are some alternatives to Kosuke?** Other AI coding tools include Claude Code, Webhook.site, Litescrape, GitHub Copilot and Cursor. **Is Kosuke safe for work data?** Kosuke says it does not train on customer code or agent transcripts, uses TLS 1.2+ in transit and AES-256 at rest, and isolates sandboxes per change; a SOC 2 Type I audit is in progress. Check your own company’s rules, and use a business plan with training turned off for client data. ## “Listed on Stepthrough” badge Add this badge to the Kosuke website, press page or docs. It links to this page, so your visitors can see the listing. Copy the HTML ```text Listed on Stepthrough ``` Checked against Kosuke’s official site on October 20, 2026: [source 1](https://kosuke.ai), [source 2](https://kosuke.ai/security), [source 3](https://kosuke.ai/pricing). Spotted something out of date? Email [rbreen@ynteractive.com](mailto:rbreen@ynteractive.com). Listings are free; [submit your AI tool](https://learn.ynteractive.com/content/ai-tools/submit). [The full AI tools directory](https://learn.ynteractive.com/content/ai-tools) · [Coding & developer](https://learn.ynteractive.com/content/ai-tools/coding-developer) · [Tool comparisons](https://learn.ynteractive.com/content/compare)