Looking for feedback on how to explain privacy for a browser-based JSON tool

I’m working on SafeJSON, a browser-based JSON toolkit for formatting, validating, diffing, decoding JWTs, querying JSONPath, and validating schemas.

The hard part has not been the formatter itself.

The hard part has been explaining privacy in a way that is accurate and believable.

I don’t want to use vague claims like “100% private” or “no tracking,” because most modern sites still have normal analytics, payments, licensing, or extension permissions.

So I’m trying to keep the promise narrower:

• no pasted-content upload for core JSON tools

• browser-local processing for pasted JSON content

• DevTools-verifiable privacy

• clear extension permission explanations

Question for other makers:

When a developer tool handles sensitive input, what makes you trust it?

A short privacy claim?

Open source?

A verification guide?

No analytics at all?

Or do most users not care unless something goes wrong?