fix(tui): handle undefined agent.current() to prevent crash on startup

[junhoyeo]

Summary

Fixes crash when local.agent.current() is called before agents are loaded (e.g., after OAuth flow or during initial startup).

Error:

TypeError: undefined is not an object (evaluating 'local.agent.current().name')
    at <anonymous> (src/cli/cmd/tui/component/prompt/index.tsx:840:75)

Root Cause

In packages/opencode/src/cli/cmd/tui/context/local.tsx, the agent store initialization assumes agents are always available:

// Before (crashes when agents() is empty)
const [agentStore, setAgentStore] = createStore<{
  current: string
}>({
  current: agents()[0].name,  // CRASH: agents()[0] is undefined
})

This happens because:

1. sync.data.agent starts as an empty array
2. LocalProvider initializes before bootstrap() fetches agents
3. Accessing agents()[0].name crashes when array is empty

Changes

packages/opencode/src/cli/cmd/tui/context/local.tsx:

• Make agent store current optional and use ?. on initialization
• Rewrite current() to safely return undefined when no agents available (matches web app implementation)
• Update set() and move() methods to handle empty agent list
• Guard currentModel memo and model functions against undefined agent
• Add null check in createEffect for agent model sync

packages/opencode/src/cli/cmd/tui/component/prompt/index.tsx:

• Add early return guard in submit() when no agent selected
• Update highlight() and spinnerDef() memos with fallback colors
• Use optional chaining with fallback in JSX display

packages/opencode/src/cli/cmd/tui/component/dialog-agent.tsx:

• Use optional chaining for current agent name prop

Testing

• Verified no TypeScript errors in modified files
• Fix aligns with the safer implementation already present in packages/app/src/context/local.tsx

[github-actions]

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Potential Duplicate PRs Found

Based on the search results, there are two highly related PRs that appear to address the same issue:

1. PR fix(tui): guard local.agent.current() after oauth redirect (fixes #7727) #7747 - fix(tui): guard local.agent.current() after oauth redirect (fixes #7727)

   • fix(tui): guard local.agent.current() after oauth redirect (fixes #7727) #7747
   • Why related: Directly addresses the same crash scenario with local.agent.current() after OAuth flow

2. PR fix(tui): handle undefined agent.current() to prevent fatal TypeError #7689 - fix(tui): handle undefined agent.current() to prevent fatal TypeError

   • fix(tui): handle undefined agent.current() to prevent fatal TypeError #7689
   • Why related: Fixes the same undefined agent crash with nearly identical title and scope

Recommendation: Check if PR #7747 or #7689 are already merged or open. If either is already in progress or merged, PR #7748 may be redundant and should be consolidated or closed.