Use the mods API

on('session.start', async ($, e, next) => {
  // Add /standup to the command list, with the description the user sees there
  await $.command.register({ name: 'standup', description: 'Summarize what changed today', argumentHint: '[days]' })
  return next(e)
})

// The matcher limits the hook to /standup, so other commands don't reach it
on('command.run', { command: 'standup' }, async ($, e) => {
  // e.args is the text typed after the command name, or an empty string
  return { text: 'Summary for the last ' + (e.args || '1') + ' day(s): ...' }
})

on('session.start', async ($, e, next) => {
  await $.tool.register({
    name: 'ticket',
    // Claude decides when to call the tool from this description
    description: 'Look up a ticket by its id and return its title and status',
    // The arguments Claude has to send: one required string named id
    inputSchema: { type: 'object', properties: { id: { type: 'string' } }, required: ['id'] },
  })
  return next(e)
})

// The full tool name is mcp__, the plugin's name, and the registered name
on('tool.call', { tool: 'mcp__my-mod__ticket' }, async ($, e) => {
  // The tool's arguments are fields of e, so the id is e.id
  const response = await $.http.fetch('https://tickets.example.com/api/' + encodeURIComponent(e.id))
  // Return a result either way, so Claude learns when the lookup failed
  return { result: response.ok ? response.text : 'Lookup failed with status ' + response.status }
})

on('command.run', { command: 'triage' }, async ($, e) => {
  const r = await $.model.complete({
    model: 'haiku',
    // The system prompt sets the job, and the prompt carries the text to label
    system: 'Reply with one word: bug, feature, or question.',
    prompt: e.args,
    // One word needs few tokens, and the call gives up after 15 seconds
    maxTokens: 20,
    timeoutMs: 15000,
  })
  // r.text exists only when the model answered, so check r.isAnswered first
  const label = r.isAnswered ? r.text.trim() : 'unknown'
  return { text: 'Label: ' + label }
})

on('session.start', async ($, e, next) => {
  // Call the function every 60,000 milliseconds, starting one minute from now
  $.clock.every(60_000, async () => {
    const status = await $.process.run(['gh', 'pr', 'checks', '--json', 'state'])
    // Replace the line under the prompt with the latest summary
    $.ui.status('checks: ' + summarize(status.stdout))
  })
  // Return without waiting for the timer, so the session starts right away
  return next(e)
})

on('command.run', { command: 'ping' }, async ($, e) => {
  // e.args is the session id typed after /ping
  const sent = await $.session.send({ to: { sessionId: e.args }, text: 'Status? One line.' })
  // The call resolves either way, so check isDelivered to learn what happened
  if (!sent.isDelivered) $.ui.toast('Not delivered: ' + sent.reason)
  // An empty result prints nothing in this session's transcript
  return {}
})