Repro — prove the bug first

| Highlight a bug. Get a failing test that proves it is real — or honest questions when it isn't — before any source is changed. |

Select a description (and optionally some code) → an agent writes a test that fails because of the bug. If it can't make a test fail, you get its questions and an untouched working tree. Only a proven bug can be fixed.

Works in VS Code and Cursor. Needs a free Cursor API key (Dashboard → Integrations). There is no Repro backend — the agent runs on your machine against your open folder.

Install

Search for Repro in the Extensions panel, or:

code   --install-extension aniket-singh-01.repro   # VS Code
cursor --install-extension aniket-singh-01.repro   # Cursor

Then set a Cursor API key under Settings → repro.apiKey, or as CURSOR_API_KEY in the environment your editor launched from.

Your project needs a test runner with a currently-passing suite. The agent establishes that baseline before it trusts any failure it produces.

What you get

1. Proof — a failing test that demonstrates the bug, opened in your editor.
2. Refusal — when the agent can't make a test fail, you get its questions instead of a confident-looking patch. Nothing in your tree changes.
3. A fix, only after proof — leaves the diff in your working tree for you to review. Never commits, never branches, never opens a PR.

Quick start

1. Install the extension in VS Code or Cursor.
2. Open a folder that has a test suite.
3. Optionally select the code you suspect.
4. Command Palette → Repro: Prove This Bug.
5. Describe the bug the way you would report it.
6. If it's proven → Fix it. Review the diff in Source Control.

Commands

Selecting code before proving attaches it as the suspected area. Both prove and fix are cancellable from the progress notification.

Settings

Why this exists

Coding agents are good at producing a confident diff for a bug that was never demonstrated to be real. The gate inverts the order: evidence first, code second. An agent that cannot make a test fail has not understood the bug, and should not be trusted to fix it.

The agent runs locally against your open folder rather than in the cloud, because the bug you're looking at is usually uncommitted — a cloud agent would clone your default branch and investigate code that doesn't contain it. That also means no GitHub App and no GitHub connection are required.

Trust & privacy

• The API key lives in your editor settings (or the environment). It is sent only to Cursor's API when you run a Repro command.
• Agent edits stay in your working tree. Repro never commits, pushes, or opens a pull request from the editor.
• There is no Repro server. Nothing about your code is sent anywhere except to the Cursor agent you invoke.
• Publisher: aniket-singh-01 on the Visual Studio Marketplace. Source: github.com/aniket-singh-01/repro-bot.

License

MIT — see LICENSE.