Your work stays yours.

Spindle for Browser is open-source software (MIT) for Google Chrome and the browsers that install from its Web Store (Microsoft Edge, Brave and others). This policy covers it however you install it: from the Chrome Web Store or from a release on GitHub. It has no account and no server of ours. What it handles stays in your browser, or goes only to the places below. We receive nothing.

What it handles, and where it goes

Your threads (your messages, the model's replies, the files you attach and the files a thread makes) are kept in the extension's own storage on this device. As a thread works, what it sends goes to the model provider you chose for it; its scripts may also call another provider you saved a key or sign-in for.
Pages, only once you turn on page reading (Settings, Pages; off when installed): the addresses and titles of your open tabs, and the text, parts and HTML of the tabs a thread reads, go to that thread's model provider. With page actions also on, a thread clicks, types and navigates in your tabs as you, and can record a tab's network requests when asked to; what it records goes to the provider too, once the thread reads it. Screenshots are saved in the thread's workspace; a model sees one only if a script sends it to one.
Your keys and sign-ins are encrypted (AES-GCM) in your browser's storage, with an optional passphrase, and sent only to the provider they were saved for (and to OpenAI's sign-in service, if you sign in with ChatGPT). For a ChatGPT sign-in, the account's e-mail address is kept with it, to show in Settings. A site's secret header that you save is encrypted the same way and sent only to that site.
Commands' network, only once you turn it on for a thread: its commands reach the websites they ask for, through your browser (without your cookies) or through a relay you set up. With a relay, names are looked up over DNS-over-HTTPS (Cloudflare), only while such a command runs.
Sites scripts may call: requests go only to the sites you list, with what the script sends.
Pages a thread makes show in a sandboxed preview that connects nowhere. If you choose Load from the web for one, it loads from websites over HTTPS, and they see those requests. If you choose Run them where the browser cannot hold a preview offline, the page's scripts could send what it shows to a website.
Your Spindle host, if you connect one: this browser's name there; for a thread whose commands run on the host, those commands and the thread's workspace files; for a thread you move there (Run on my host), the whole thread, its conversation and workspace, and while it runs there, what this browser's page tools read for it. The host is yours, and it sends that thread's model requests to the provider signed in on it.

What we receive

Nothing. Spindle has no analytics, telemetry, advertising or tracking, and sends us no data. We never sell or transfer your data, and we use none of it: Spindle uses it only to do what you ask a thread to do. No person at SiliconState reads it.

Who else processes it

The model providers you choose (for example OpenAI, Anthropic, DeepSeek, Z.ai, Moonshot, or a model server you run) process what your threads send them under their own privacy policies. So do the services you set up or list: a relay (and Cloudflare's DNS, for the names commands look up through it), the sites you list for scripts, and the provider signed in on your Spindle host, for threads you run there. Websites your threads visit see those visits, as they would yours.

How long it is kept

On your device, until you delete the thread or remove the extension (which deletes everything it keeps; files you saved, .spindle files and threads on your Spindle host stay where they are). A key or sign-in stays until you remove it in Settings, and a site's secret header until you remove the site; if you forget your passphrase, Forgot it deletes them all. Deleted records may linger in the browser's storage files until it compacts them. Your threads are protected by your browser profile; only keys and secrets are encrypted inside it.

Limited Use

Spindle's use of the information it handles complies with the Chrome Web Store User Data Policy, including the Limited Use requirements: it is used only to do what you ask a thread to do.

Children

Spindle is not directed at children under 13.

Changes and questions

Changes to this policy are published on this page, with its date. Ask about it, or about anything Spindle does, on GitHub; the source code shows exactly what it does.