Agent Snippet

## TrueSeal

This app syncs data between devices with TrueSeal. Before you write or change code that uses TrueSeal, read https://trueseal.dev/llms.txt and take every API name, limit, error case and version from the pages it lists.

- Register the `onMessage` handler when the app starts. Nothing is received until it is registered.
- Store or apply each message before the `onMessage` handler returns, and await that work inside the handler. The library acks the message to the relay when the handler returns, so work still running in the background is lost if the app is killed before it finishes.
- Key stored messages by their `MessageId`, so that handling one twice changes nothing. A message arrives again if the app crashed while handling it.
- Pairing needs an action by the user on both devices. On the admitting device, call `accept(request)` only after the user confirms the request comes from the device in front of them. The name in a request is a label the device chose and proves nothing. On the joining device, call `join(token)` only with a token the user scanned or pasted from the admitting device.
- Describe TrueSeal to users only with what https://trueseal.dev/agents/what-trueseal-is.md says it does and does not do.

The TrueSeal Skills walk through integrating, pairing and running a relay. In Claude Code, run `/plugin marketplace add julianbonomini/trueseal-skills`, then `/plugin install trueseal@trueseal-skills`. In other agents, run `npx skills add julianbonomini/trueseal-skills`.