Tokenwatch handles your Claude Code login, so this page states exactly what it reads, sends, stores and logs.

• The access token is sent only to api.anthropic.com, over HTTPS, in the Authorization header. If you set VS Code's http.proxy, the request goes through that proxy like any other VS Code extension traffic.
• The token is read again for every request and kept in memory only while that request runs.
• Nothing from your transcripts leaves your machine.
• There is no telemetry or analytics, and no other network call.

Besides the log (below), Tokenwatch stores one small record in VS Code's extension storage (globalState, key tokenwatch.lastQuota):

• the last usage response (percentages and reset times),
• when it was fetched,
• the time a rate-limit backoff ends.

This lets a reloaded window show your numbers at once without sending a request. It never contains the token.

The Tokenwatch output channel, which VS Code also saves under its logs folder, records:

• the status bar's one-line summary, on each quota refresh and whenever ctx changes;
• request errors, with the HTTP status, up to 200 characters of the server's error response, and the Retry-After value when there is one;
• when the endpoint's reply isn't recognised, up to 1,000 characters of that reply;
• rate-limit notes (Backing off polling for 180s…, Manual refresh skipped…);
• when no session is found, the paths of the folders open in the window (Context: no Claude Code session found for [/Users/you/project]);
• at Debug level only, what was restored after a reload.

It never contains the access token or the refresh token. A unit test (src/test/application/usageService.test.ts) checks this for every refresh outcome. Before pasting log lines into an issue, check them for folder paths or response bodies you'd rather not share.

• It doesn't use the refresh token, and never writes to the Keychain or the credentials file.
• It doesn't send anything anywhere except the one request above.
• It has no runtime dependencies. All the code that runs is in src/, compiled.

Please report security issues privately through GitHub's private vulnerability reporting, not as a public issue.