Windows: OpenCode agent unavailable natively (win32 list is WSL-only), and the WSL fallback fails on a docker-desktop-only WSL setup

[cfoellmann]

Problem to solve

On Windows, OpenCode cannot be selected as an agent even when a working native opencode is on PATH (installed globally via npm, so %APPDATA%\npm\opencode.cmd resolves fine from cmd/PowerShell). The agent simply does not appear in the picker, with no hint as to why.

The only Windows option is Open Code (WSL), which is a much heavier requirement than it needs to be — and it fails outright for users whose only WSL distro is Docker Desktop's utility VM.

Root cause (from app.asar)

The agent catalogue is platform-keyed, and OPENCODE is absent from the win32 list:

default: [CLAUDE, CODEX, COPILOT, ANTIGRAVITY, GEMINI, AMP, GOOSE, QWEN, AUGGIE,
          MISTRAL_VIBE, CURSOR, Q, ROVO, AIDER, OPENCODE, CRUSH, CLINE, PLANDEX, DROID, QODO]

win32:   [CLAUDE, CODEX, COPILOT, ANTIGRAVITY, GEMINI, AMP, GOOSE, QWEN, AUGGIE,
          MISTRAL_VIBE, CURSOR, Q, ROVO, AIDER, CLINE, QODO,        // native
          CLAUDE_WSL, ..., AIDER_WSL, OPENCODE_WSL, CRUSH_WSL,
          CLINE_WSL, PLANDEX_WSL, DROID_WSL, QODO_WSL]              // WSL

Consistent with that, the OPENCODE definition has no win32 entry in installCommands:

[OPENCODE]: { label: "Open Code", checkCommand: "opencode", binaryName: "opencode",
              versionFlag: "--version", isWsl: false, requiresNode: false,
              installCommands: { darwin: "curl -fsSL https://opencode.ai/install | bash",
                                 linux:  "curl -fsSL https://opencode.ai/install | bash" } }

So checkAiAgent('opencode') is never invoked on Windows and PATH is irrelevant. Note the .cmd-suffix helper for non-WSL win32 agents already exists and is applied to every other native agent, so the machinery for a native Windows check appears to be in place.

Secondary issue: the WSL fallback fails silently in the UI

With Docker Desktop installed and no other distro, docker-desktop is the default WSL distro. It has no /bin/bash and no curl, so both the install command (wsl curl -fsSL https://opencode.ai/install | bash) and checkCommandInWSL fail:

[2026-08-23 23:28:47.693] [info]  [invariant:start] agent-install:opencode-wsl { agent: 'opencode-wsl', platform: 'win32' }
[2026-08-23 23:28:51.403] [error] [invariant:fail] agent-install:opencode-wsl {
  agent: 'opencode-wsl',
  platform: 'win32',
  exitCode: 1,
  durationMs: 3706,
  stdout: '',
  stderr: '<3>WSL (11 - Relay) ERROR: CreateProcessCommon:818: execvpe(/bin/bash) failed: No such file or directory\n' +
    '/bin/sh: curl: not found\n',
  fulfillmentMs: 3711,
  timedOut: false
}

The log records this, but the UI gives no actionable message — the user just sees an agent that will not install.

Proposed solution

1. Add OPENCODE to the win32 agent list and give it a win32 entry in installCommands (e.g. npm i -g opencode-ai, or point at the official Windows install path). OpenCode ships a working Windows binary; the existing .cmd resolution should then detect an already-installed one on PATH.
2. Treat CRUSH, PLANDEX and DROID the same way if they also have native Windows builds — they are currently in the same WSL-only bucket.
3. When a WSL-backed agent check/install fails because the default distro is unusable (Docker Desktop's utility VM being the common case), surface a specific message such as "Default WSL distro docker-desktop cannot run this installer — install a full distro (wsl --install -d Ubuntu) or select a different one" instead of a generic failure.

Acceptance criteria: on Windows with opencode --version working in a normal shell, "Open Code" appears in the agent picker and is detected as installed, with no WSL requirement.

Alternatives considered

• Installing a full WSL distro alongside docker-desktop and setting it as default — works, but changes the machine-wide default distro purely to satisfy one agent, and requires maintaining a second OpenCode install/auth inside WSL.
• Patching app.asar locally to add OPENCODE to the win32 array — effective, but overwritten by every app update.

Environment

• DevSwarm 2.5.1 (Windows installer build)
• Windows 11 Pro 26200
• opencode installed globally via npm; %APPDATA%\npm\opencode.cmd present and on PATH
• WSL: single distro docker-desktop (Version 2, default)