Terminal restore hook: run a command when terminal tab is re-opened after restart

[axsuul]

What are you proposing?

A way to configure a terminal tab so that when Zed restarts and restores the workspace, it runs a specified command to restore the previous session in that terminal tab.

This could be a per-terminal setting, an escape sequence the program emits to register a restore command, or a hook in Zed's terminal configuration.

Why does this matter?

I run OpenCode (a terminal-based AI coding agent) across multiple terminal tabs in Zed. When Zed restarts (e.g., after an update), all terminal processes are killed and the tabs re-open as empty shells. There's no way for a program like OpenCode to automatically resume its session in the restored terminal tab.

Having a restore hook would allow terminal-based tools to register a command that Zed runs on restart, enabling seamless session recovery without manual intervention.

Are there any examples or context?

• Related discussion: Resumable terminal sessions (like tmux, zellij) across zed reloads #25227 (Resumable terminal sessions like tmux/zellij across Zed reloads) — focuses on persisting the terminal process itself, whereas this request is about a lighter-weight hook for programs to restore their own sessions
• Terminal-based tools like OpenCode have their own session management and just need Zed to re-invoke a restore command (e.g., opencode --restore <session-id>)

Possible approach

• Allow a running program to register a restore command via an escape sequence (e.g., an OSC sequence that tells Zed "if this terminal is restored, run this command")
• Zed serializes the restore command alongside the terminal tab's workspace state
• On restart, instead of opening a bare shell, Zed runs the registered restore command in the terminal tab
• This would be opt-in and only apply to terminals where a program has explicitly registered a restore command

[chenwuji2000-cyber]

For reference, Zed's Agent Panel already supports session history restoration for external agents as of v0.225.9 (see Discussion #41140, PR #49449).

However, this only covers the Agent Panel integration. What we still need is the ability to restore external agent sessions from Zed Terminal tabs — which is exactly what this discussion is about.

Many users (myself included) run agents like Claude Code, OpenCode, etc. directly in terminal tabs rather than through the Agent Panel. When Zed restarts, these terminal processes are killed and we lose the active session. A lightweight restore hook — where the agent registers a restore command (e.g., claude --resume <session-id>) that Zed re-executes on restart — would bridge this gap nicely.