What is the CMD+K widget postMessage API?

Host → widget messages

Post these to your own window (the loader listens for same-window messages) from anywhere in your app:

• cmdk:host:open — open the chat. Optional payload: { text?: string, submit?: boolean } — text prefills the composer, and submit (default true when text is present) sends it immediately.
• cmdk:host:close — close the chat. No payload.
• cmdk:host:toggle — toggle open/closed. No payload.
• cmdk:host:set_theme — switch theme. Payload: { theme: "light" | "dark" | "auto" }.

The window.CommandK functions

The loader exposes the same controls (plus walkthrough helpers) as plain functions:

CommandK.open(text?, submit?)   // open, optionally prefill/send
CommandK.close()               // close
CommandK.toggle()              // toggle
CommandK.isOpen()              // boolean
CommandK.setTheme("dark")      // "light" | "dark" | "auto"
CommandK.startWalkthrough(id)  // run a published guided tour by id
CommandK.listWalkthroughs()    // [{ id, name }]
CommandK.snoozeWalkthroughs(ms)
CommandK.resetWalkthroughs()   // clear first-visit/opt-out flags (QA)
CommandK.fireTourEvent(name)   // trigger event-based tours

window.CommandK exists from the moment the loader script runs, before the widget has finished booting. A call made in that first moment — a click on your own “Ask AI” button right after a page load — is queued and replayed as soon as the widget is ready, so the first click always opens the panel. The same is true for cmdk:host:*messages posted early.

Custom launcher example

<button id="ask-ai">Ask AI</button>
<script>
  document.getElementById("ask-ai").addEventListener("click", () => {
    window.postMessage(
      { type: "cmdk:host:open", text: "How do I invite my team?" },
      window.location.origin
    );
    // …or equivalently: window.CommandK.open("How do I invite my team?");
  });
</script>

Pair this with data-cmdk-launcher="custom" if you want the loader to inject no launcher of its own.

What about widget → host messages?

The chat iframe and the loader exchange their own messages (cmdk:ready, cmdk:init, cmdk:close, page-context, walkthrough, and consent-gated page-action requests). These are an internal transport between the two CMD+K components, not a public event stream for your page — don't build on them from host code. The complete inventory, published for transparency and versioned as v1 (stable), lives in the partner embed guide.