feat: allow empty /btw command

[kermanx]

Related Issue

No linked issue. This addresses the limitation that /btw required a question inline instead of allowing users to open the side-channel panel first.

Problem

Users who invoke /btw without arguments currently get a usage error, so they cannot open the side-channel panel first and type the question there.

What changed

• Allows /btw with no arguments to start the side agent and mount the existing BTW panel in its empty state.
• Routes the first typed panel input through the existing /btw prompt flow, and cancels an unused empty side agent when the panel is closed.
• Updates the bilingual slash command reference and adds TUI coverage for empty /btw, first panel input, and closing an unused empty panel.

Validation:

• pnpm --filter @moonshot-ai/kimi-code test -- test/tui/commands/resolve.test.ts test/tui/kimi-tui-message-flow.test.ts --runInBand
• pnpm --filter kimi-code-docs run build
• Read-only diff audit for context-specific internal identifiers: no issues found.

Checklist

• I have read the CONTRIBUTING document.
• I have linked a related issue, or explained the problem above.
• I have added tests that prove my feature works.
• Ran gen-changesets skill, or this PR needs no changeset.
• Ran gen-docs skill, or this PR needs no doc update.

[changeset-bot]

🦋 Changeset detected

Latest commit: c1ae2bb

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@moonshot-ai/kimi-code	Minor

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[pkg-pr-new]

pnpm dlx https://pkg.pr.new/@moonshot-ai/kimi-code@c1ae2bb

npx https://pkg.pr.new/@moonshot-ai/kimi-code@c1ae2bb

commit: c1ae2bb

[chatgpt-codex-connector]

💡 Codex Review

kimi-code/apps/kimi-code/src/tui/commands/btw.ts

Lines 15 to 16 in 297f913

	const agentId = await session.startBtw();
	host.btwPanelController.open(agentId, prompt);

Defer forking /btw until the first panel prompt

When /btw is opened without arguments during an active main turn, this forks the side agent immediately, before the user types the panel question. startBtw() snapshots the parent context in SessionSubagentHost.startBtw() via useProjectedHistoryFrom(parent.context), so any main-agent output or tool results that arrive while the empty panel is open are missing from the first side question. Please defer startBtw() until the first non-empty panel submit, or refresh the snapshot, so empty /btw behaves like /btw <question> at submission time.

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[chatgpt-codex-connector]

💡 Codex Review

kimi-code/apps/kimi-code/src/tui/commands/btw.ts

Lines 15 to 16 in c1ae2bb

	const agentId = await session.startBtw();
	host.btwPanelController.open(agentId, prompt);

Mount the empty /btw panel before awaiting startBtw

When /btw is invoked without arguments, the panel is not mounted until session.startBtw() resolves. Because dispatchInput fires slash-command execution without awaiting it, if startBtw() is slow and the user types the intended side question immediately, btwPanelController.sendUserInput() still sees no active panel and the text falls through to the main prompt/queue instead of the new side agent. The inline /btw question path is safe because the prompt is captured before this await, but the new empty-panel flow needs to reserve/mount the panel or otherwise buffer the first input while the side agent is starting.

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".