## Houston 0.4.21

A reliability release. A more reliable Stop button, installed skills show up, and a few provider papercuts are gone. Drop-in on top of 0.4.20, no breaking changes.

### Changed

- **Latest Claude Code under the hood.** Houston now bundles the newest version of Claude Code that powers your Claude agents, so they run on Anthropic's most recent fixes and improvements.

### Fixed

- **More reliable Stop button.** The Stop button already worked, but in some cases an agent could keep going in the background, especially when it had started subagents or other helper tasks. Stop now reliably halts the agent and everything it started, even mid-thought or right after you send a message. While an agent is working, the send button also shows a clear stop icon, so you always know how to halt it.
- **Agents with a lot of context start again on Windows.** A busy agent that had built up a large amount of memory and notes could fail to start on Windows. That is fixed, so even your most-used agents launch normally.
- **Installed skills show up.** A skill you install now appears for your agent right away and stays in sync if the agent later updates it. This was most noticeable on Windows, where installed skills could stay hidden.
- **The Connect prompt only shows where it belongs.** A "Connect Claude" button used to appear in chats that do not use Claude, like an OpenAI chat, and stick around. Now a reconnect prompt only ever shows for the provider that chat actually uses.

### Before you upgrade

- **Mac:** quit Houston before installing. macOS does not always replace a running app cleanly. If in doubt, remove `/Applications/Houston.app` and drag the new copy in.
- **Windows x64:** auto-update from 0.4.7 or later pulls you forward automatically. The MSI is still not OS-code-signed (SignPath integration still pending), so Windows SmartScreen may warn on a fresh install.
- **Windows ARM64:** there is no auto-update path from an emulated x64 install. Download the ARM64 MSI manually, uninstall the x64 build first, then install the ARM64 one.
