tab-mcp.ractive.ch connects an AI app, such as Claude, to a page of
this site that is open in your browser, for example the
saturnus calculator. It runs
tab-mcp, an open-source relay.
Nothing goes through it until you click Connect on the page and pair your AI app
with the code the page shows.
What passes through
While a page is connected, every request the AI app sends to the page and every answer the page gives travel through the relay: the tool name, its arguments and its result. For saturnus that is, for example, the keys to press and what the calculator shows. The connection is encrypted between your browser and the relay and between the AI app and the relay, but the relay itself reads this traffic in clear text, because it has to pass it on.
The relay passes this content on and forgets it. It does not store it and does not write it to its logs.
What is stored
When you pair an AI app, the relay stores a grant:
- a random id for the page's connection address;
- the AI app's client id (a web address) and the name it gives itself;
- the permissions granted and when the grant was made and used;
- SHA-256 hashes of the app's access and refresh tokens. A hash cannot be used as a token, so a copy of the stored data cannot connect anything.
No names, no email addresses, no IP addresses and no tool contents are stored. A grant ends when you disconnect the app on the page, and 90 days after pairing at the latest. Access tokens last one hour.
Logs
The relay logs events such as "a page connected" or "a request took too long", with shortened ids. Logs never contain requests, answers, tokens or codes. An IP address appears only when a rate limit is hit, and then shortened (the last part removed). Your IP address is used, in memory only, to limit how many sessions one address can open.
Where it runs
The relay runs on bunny.net (BunnyWay d.o.o., Slovenia) in Germany, and its traffic passes through bunny.net's CDN. Like any hosting provider, bunny.net processes connection data such as IP addresses to deliver the traffic. Its access logs for the relay keep IP addresses only with the last part removed. See bunny.net's privacy policy.
Questions
Open an issue at github.com/ractive/tab-mcp.