[kube]

Summary

Before this PR, Petrinaut AI on the demo site was the library's built-in chat, which the demo shell configured through the aiAssistant prop. The AI experiments demo used the same prop.

Plugin API gains what that chat needs: focus, collapse, start requests, a start action in the empty-canvas prompt and a preview. Website now has its own copy of the chat in plugins/_shared/chat. AssistantChat takes the plugin's api and a configuration with the PetrinautAiAssistant fields, and renders in the assistant panel through the plugin API. Petrinaut AI and the AI experiments demo are plugins that render it, with a title in the title bar. Brunch's chat comes through the aiAssistant prop in this PR.

Links

• Docs Writing a plugin › Provide the AI assistant
• Docs Plugin API reference
• Docs The demo site's plugins

Changes

Plugin API

• useAssistantPanel() adds focus, collapse and the start request

  focusRequest changes each time the user opens the panel.
  collapsed and setCollapsed shrink the panel to a dock in the corner and hide its title bar.
  startRequest holds the empty-canvas prompt's { text } or { action } until consumeStartRequest().

• Empty-canvas prompt serves plugin assistants

  A typed message becomes the start request.
  assistant.startAction shows in place of Send while the input is empty.

• AssistantPanelTitle takes onClose

  It runs when the user presses Close, before the panel closes.

• AssistantPanelPreview renders an assistant's content outside an editor, for stories and tests
• /ui exports AiAssistantIcon, HorizontalTabsHeader and useExperimentalIconPackEnabled

  Chat kit draws the same title bar icon and tabs as the editor.
  /ui/plugin exports ExperimentRecord for its experiment cards.

Chat kit

• plugins/_shared/chat holds a copy of the library's chat

  Transcript, composer, tool cards, experiment cards, transports and the Voice dock, with their tests.

• AssistantChat reaches the editor only through the plugin api

  Edits run through document.edit and diagnostics through document.diagnose().
  Experiments run through experiments.run, and tool cards reveal through editor.reveal.

• Chat fills the panel through AssistantPanelTitle and useAssistantPanel

  Title bar shows tabs when the configuration has an additionalTab, and a title otherwise.
  Empty-canvas prompt's message or Voice start request starts the chat.

• Kit's presentation option is deprecated

  Brunch-only UI moves into the Brunch plugin, and each assistant plugin renders its own transcript.

• @ai-sdk/react, @ark-ui/react and vscode-languageserver-types join the website's dependencies
• Tests compile the chat kit with the React Compiler

  React Compiler lint rules are errors under plugins/_shared/chat.
  vitest.setup.ts shims matchMedia for jsdom.

Plugins

• Petrinaut AI is the website.petrinaut-ai plugin

  It renders the chat over /api/chat and saves each document's transcript in local storage.
  Demo shell passes it while Brunch's assistant is not ready.

• /ai-experiments passes its scripted assistant as the website.ai-experiments-demo plugin

Test coverage

• editor-assistant.test.tsx, ai-cta-modal.test.tsx:

  Close handler order, a start action's request until consumed, and the prompt's start action in place of Send.

• Suites under plugins/_shared/chat:

  Run the chat in AssistantPanelPreview against an api from createTestPluginApi, tabs from additionalTab included.

• petrinaut-ai/plugin.test.tsx:

  Empty-net prompt starts a chat in the real editor that edits the net and saves the transcript under the document's id.

• use-local-storage-ai-messages.test.ts:

  One document's transcript replaced and cleared, the others kept.

• local-storage-demo-app.test.tsx:

  Stock assistant default, Brunch selection and each assistant's own history, with Petrinaut AI as a plugin.

How to test

Petrinaut AI

• Open Petrinaut preview on Vercel
• Menu > New

  Expect empty-net prompt

• Submit Build an SIR model in prompt

  Expect panel titled AI and net built

• Reload page
• Bottom bar > Show AI assistant

  Expect conversation restored

• Menu > User settings > Plugins

  Expect Petrinaut AI tagged Assistant

AI experiments demo

• Open AI experiments demo on Vercel
• Bottom bar > Show AI assistant
• Send run

  Expect experiment progress, then result card

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