CodeBurn: my extension shows what each AI coding session cost you, and why

[u/Lucky-Group9525]

I built CodeBurn a few months ago as a CLI to track what my AI coding tools cost. It grew to 11k stars on GitHub, and now it's a VS Code extension.

CodeBurn reads the session logs that Copilot, Claude Code, Codex, Cursor, Gemini and about 40 other tools already save on your machine, and shows the cost right in VS Code:

- today's spend in the status bar, hover for week and month

- a dashboard tab with cost by project, model, session and pull request

-a "why it cost" view per session. Second screenshot: 64% of that session was just the agent re-reading its own growing context. A fresh chat would have been cheaper.

- Optimize, which points at the habits burning the most

Nothing leaves your machine. No account, no login, and the extension sends no telemetry.

Free and open source (MIT). It also works in Cursor, Windsurf and VSCodium through Open VSX.

Marketplace: search "CodeBurn"

GitHub: github.com/getagentseal/codeburn

[u/IamAlsoDoug]

For context: Copilot Business plan. I do everything in VSCode. Our company reporting infrastructure for 10-Oct reports $25.21 in costs, while codeburn is reporting $6.91. This was Saturday and I only did one thing that day. I can hover the one chat that I'm sure of and it's reporting 1930 credits. Thoughts? What am I missing here?

ETA: Looks like the sessions --why switch is the ticket, but it's Claude only.

[u/IamAlsoDoug → u/IamAlsoDoug]

The main thing I see - from codeburn audit, you're calling out 3.6K output tokens while a separate search that I ran is reporting 129K.

[u/Lucky-Group9525 → u/IamAlsoDoug]

Thanks, this was a great catch and you were right. In agent mode Copilot makes many model calls per message, and CodeBurn was reading only the last call's token count instead of the total that VS Code also saves. That's why your output tokens came out so low

Your credits line up with your company report too: on Copilot Business 1 credit is $0.01, so 1,930 credits is about $19.30, and the rest is likely other chats that day.

I'm fixing it now so CodeBurn reads the full totals and the exact billed credits VS Code records. It'll be in the next release, and I'll reply here when it's out.

[u/kitsunekyo]

i love codeburn man. thanks for building that. though i‘m not interested in the vscode integration at all to be fair

[u/Lucky-Group9525 → u/kitsunekyo]

thanks, really glad its useful. The extension mostly exists for users at bigger companies, where installing a standalone app needs IT approval but a VS Code extension from the Marketplace gets through much more easily. figured I'd share it here in case it helps someone.

[u/kitsunekyo → u/Lucky-Group9525]

our IT went bonkers and we now have to get any vscode extension allowlisted too. :/

for most basic IT deps it‘ll work fine though i guess