Kanna plugins

A Kanna plugin adds UI to Kanna itself: a page in the sidebar, a panel in the chat footer, an entry in the / picker. Its server half runs in its own process and talks to Kanna over typed RPC, so a misbehaving plugin cannot take the server down with it.

This is not the same thing as a Claude Code or Codex plugin. Those add skills and commands to the agent and are managed under Settings → Plugins; see Package auto-update.

Turn plugins on

Plugins are off by default. While they are off, every plugin route, tool and UI surface stays dark. Turn them on in ~/.kanna/data/settings.json:

{
  "plugins": { "enabled": true }
}

A Settings → Kanna plugins page then appears, listing what is installed.

Write one

A plugin is a directory with a manifest and an entry file. Ask the agent to scaffold one (plugin_scaffold), or write the three files yourself:

{
  "id": "hello",
  "name": "Hello",
  "version": "0.1.0",
  "kannaPluginApi": 1
}

import type { PluginContext } from "@kanna/plugin"
import { Panel } from "./panel.client"

export default function contribute(plugin: PluginContext) {
  plugin.addSurface("main", Panel)
  plugin.addSidebarItem({ id: "main", title: "Hello", icon: "Blocks", surface: "main" })
  plugin.addCommandCenterItem({
    name: "greet",
    description: "Say hello",
    prompt: "Say hello to the team in one sentence.",
  })
  return () => {}
}

import type { PluginSurfaceProps } from "@kanna/plugin"

export function Panel({ theme }: PluginSurfaceProps) {
  return <div style={{ color: theme.colors.foreground }}>Hello is running.</div>
}

The id is lowercase letters, digits and hyphens, starts with a letter, and kanna is reserved. entry in the manifest defaults to index.ts.

What a plugin can contribute:

Call	Adds
`addSurface(id, Component)`	A React component, shown as a panel in the chat footer
`addSidebarItem({ id, title, icon, surface })`	A sidebar entry that opens one of your surfaces as a page
`addCommandCenterItem({ name, description, prompt })`	A `/` picker entry, listed as `<pluginId>:<name>`
`handle(contract, handler)`	A server-side RPC handler, with `defineRpc` from `@kanna/plugin/server`

Selecting a plugin’s / entry inserts its prompt text into the composer, so it works on every provider. A plugin can add picker entries but never replace one: if the name is already taken, the plugin’s entry is dropped.

Install and manage

Kanna compiles the directory into a browser bundle and a server bundle, stores them under ~/.kanna/plugins/<id>/, and remembers the install across restarts.

kanna plugin install ./my-plugin   # compile and install from a directory
kanna plugin ls                    # list installed plugins and their state
kanna plugin reload hello          # restart it, picking up a rebuilt bundle
kanna plugin logs hello --tail 50  # the plugin's most recent log lines

The agent has the same verbs as tools (plugin_scaffold, plugin_validate, plugin_install, plugin_list, plugin_reload, plugin_logs), so you can ask a chat to build and iterate on a plugin for you.

Each compile runs in a separate process with a 20-second deadline. A build that hangs fails cleanly instead of freezing Kanna.