[FEATURE]: Config option to auto-attach to a remote server

[kldzj]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

Problem

Users running a persistent opencode serve instance must manually use opencode attach <url> instead of opencode. This is easy to forget and disrupts workflow.

Proposed Solution

Add a config option to specify a default attach URL:

{
  "server": {
    "attach": "http://10.0.0.1:4096"
  }
}

Or environment variable:

OPENCODE_ATTACH_URL=http://10.0.0.1:4096

Behavior

If configured and the server is reachable:

• opencode attaches automatically (equivalent to opencode attach <url>)

If unreachable:

• Falls back to starting a new embedded server

Current Workaround

Shell wrapper, but this doesn't work in IDE extensions or scripts.

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• [FEATURE]: Server Registry & Auto-Discovery for Persistent Sessions #8948: Proposes a Server Registry & Auto-Discovery mechanism where opencode automatically detects and connects to an existing opencode serve instance for the current directory — very similar problem and proposed behavior.
• [FEATURE]: Named Remote Connections with Session Origin Tracking #6461: Named Remote Connections with Session Origin Tracking — also addresses persistent remote server connection management.

If your request is meaningfully different from those, please clarify how it differs.

[kldzj]

One could argue that #8948 does this in a similar fashion, but I'd prefer something that can be globally configured, not just per directory.

[jensenojs]

+1 with a concrete use case. The opencode.nvim plugin supports connecting to a running opencode serve for bidirectional TUI/nvim sync — edits and context are live-shared between both interfaces:

Today this requires a shell wrapper to manage the server + attach flow, exactly the friction this proposal would eliminate. nvim already knows how to discover a server by port; it's the TUI side that's missing "prefer existing server over embedded."

[jensenojs]

I have a prototype for this and may open a PR.

It adds a server.attach config value. When set, the default opencode TUI path checks /global/health and attaches to that server; when unset, current embedded behavior stays unchanged.

For local shared servers, the prototype can start opencode serve when needed, and the auto-started server shuts down after the last client disconnects.