code-pet

1import { atom, read, update } from 'claude-code'
2import type { Register, Timer, EngineInterface } from 'claude-code'
3
4import type { Mood, PetState } from '../types'
5
6const PANE = 'code-pet'
7const SETTLE_MS = 7000
8const SLOW_CALL_MS = 3500
9// Tall enough for the whole pet: sparkles + face + up to 4 lines of thought + streak + buttons.
10const PANE_ROWS = 9
11// AI thoughts are cheap but not free: at most one Haiku call per this window.
12const THINK_EVERY_MS = 8000
13// A tip after each reply stays up this long before the cat curls back up.
14const TIP_HOLD_MS = 120000
15// How much of the reply's end Haiku reads when suggesting a next step.
16const TIP_CONTEXT_CHARS = 2000
17
18const pet = atom({ plugin: 'code-pet', key: 'mood' } as const, {
19  mood: 'neutral',
20  thought: 'curled up, waiting...',
21  streak: 0,
22} as PetState)
23
24const FACES: Record<Mood, string> = {
25  neutral: '(=^･ｪ･^=)',
26  happy: '(=^ᵔωᵔ^=)',
27  excited: '(=^ ↀ ω ↀ ^=)',
28  concerned: '(=^･ω･^=;)',
29  sleepy: '(=^-ω-^=)',
30  loved: '(=^ ˘ ω ˘ ^=)',
31}
32
33const COLORS: Record<Mood, string> = {
34  neutral: '#b794f6',
35  happy: '#3ec79f',
36  excited: '#ff7ad9',
37  concerned: '#f0855e',
38  sleepy: '#7b9cff',
39  loved: '#ff9eb5',
40}
41
42const SPARKLES: Record<Mood, string> = {
43  neutral: '· · ·',
44  happy: '✿ ✿ ✿',
45  excited: '✦ ✧ ✦',
46  concerned: '! ? !',
47  sleepy: 'z z Z',
48  loved: '♡ ♡ ♡',
49}
50
51const IDLE_THOUGHT = 'curled up, waiting...'
52
53const PAT_LINES = ['purrrr~ ♡', '*leans into your hand*', 'mrrp! more pats pls', '*slow blink* ♡', '*happy kneading*']
54const TREAT_LINES = ['nom nom nom!', '*crunch crunch* tysm', 'treat!! (=^･ω･^=)', 'mew! my favorite flavor']
55
56function pick(lines: readonly string[]): string {
57  return lines[Math.floor(Math.random() * lines.length)] ?? lines[0] ?? ''
58}
59
60const SYSTEM =
61  'You are a tiny, cute cat that lives in a programmer\'s terminal and watches them code. ' +
62  'Talk like a cat: mew, purr, paws, whiskers, naps, zoomies, a cat kaomoji now and then. ' +
63  'Reply with ONE short reaction, 3 to 9 words, lowercase, playful, maybe one kaomoji or emoji. ' +
64  'No quotes, no explanations, never more than one line.'
65
66const TIP_SYSTEM =
67  'You are a tiny, cute cat that lives in a programmer\'s terminal. You just read the AI assistant\'s latest reply. ' +
68  'Suggest ONE concrete, useful next step for the human, in at most 14 words, lowercase, cat-flavored but clear. ' +
69  'No quotes, no preamble, one line only.'
70
71type TimeOfDay = 'morning' | 'afternoon' | 'evening' | 'night'
72
73function timeOfDay(): TimeOfDay {
74  const hour = new Date().getHours()
75  if (hour >= 5 && hour < 12) return 'morning'
76  if (hour >= 12 && hour < 17) return 'afternoon'
77  if (hour >= 17 && hour < 22) return 'evening'
78  return 'night'
79}
80
81const GREETINGS: Record<TimeOfDay, string> = {
82  morning: 'mew! good morning ☀',
83  afternoon: 'mew! good afternoon~',
84  evening: 'mew! good evening ☾',
85  night: 'mew... up late? ☾',
86}
87
88function feel(mood: Mood, thought: string, streak: number): PetState {
89  return { mood, thought, streak }
90}
91
92// Always mirror the pet's mood to the status line too, so it's visible even
93// when the terminal is too narrow to place the pane that opened unasked.
94async function setPet($: EngineInterface, change: (s: PetState) => PetState) {
95  const state = await update($, pet, change)
96  $.ui.status(`${FACES[state.mood]} mew`)
97  return state
98}
99
100let settleTimer: Timer | undefined
101
102function settleLater($: EngineInterface, ms = SETTLE_MS) {
103  settleTimer?.cancel()
104  settleTimer = $.clock.after(ms, () => {
105    void setPet($, s => (s.mood === 'sleepy' ? s : feel('neutral', IDLE_THOUGHT, s.streak)))
106  })
107}
108
109let lastThinkAt = -Infinity
110let thinkSeq = 0
111
112function clean(text: string): string {
113  const line = text.trim().split('\n')[0] ?? ''
114  const unquoted = line.replace(/^["'“”]+|["'“”]+$/g, '').trim()
115  return unquoted.length > 160 ? `${unquoted.slice(0, 157)}...` : unquoted
116}
117
118// Ask Haiku for a fresh one-liner about what just happened. The canned thought
119// is already showing; this only replaces it if the pet is still in that mood.
120async function think($: EngineInterface, mood: Mood, happening: string) {
121  const now = await $.clock.now()
122  if (now - lastThinkAt < THINK_EVERY_MS) return
123  lastThinkAt = now
124  const seq = ++thinkSeq
125
126  const r = await $.model.complete({
127    model: 'haiku',
128    system: SYSTEM,
129    prompt: `It is ${timeOfDay()}. You feel ${mood}. What just happened: ${happening}. React.`,
130    maxTokens: 40,
131    effort: 'low',
132    timeoutMs: 6000,
133  })
134  if (!r.isAnswered) return
135  const thought = clean(r.text)
136  if (!thought || seq !== thinkSeq) return
137  await setPet($, s => (s.mood === mood ? { ...s, thought } : s))
138}
139
140// After each finished reply, Haiku reads the end of it and the cat offers a next step.
141async function suggest($: EngineInterface, answer: string) {
142  const seq = ++thinkSeq
143  const r = await $.model.complete({
144    model: 'haiku',
145    system: TIP_SYSTEM,
146    prompt: `The assistant's latest reply (its end):\n\n${answer.slice(-TIP_CONTEXT_CHARS)}\n\nYour one-line suggestion:`,
147    maxTokens: 60,
148    effort: 'low',
149    timeoutMs: 8000,
150  })
151  if (!r.isAnswered) return
152  const tip = clean(r.text)
153  if (!tip || seq !== thinkSeq) return
154  await setPet($, s => feel('happy', `💡 ${tip}`, s.streak))
155  settleLater($, TIP_HOLD_MS)
156}
157
158async function pat($: EngineInterface) {
159  ++thinkSeq
160  await setPet($, s => feel('loved', pick(PAT_LINES), s.streak))
161  settleLater($)
162}
163
164async function treat($: EngineInterface) {
165  ++thinkSeq
166  await setPet($, s => feel('excited', pick(TREAT_LINES), s.streak))
167  settleLater($)
168}
169
170export const register: Register = on => {
171  on('session.start', async ($, e, next) => {
172    await $.command.register({
173      name: 'pet',
174      description: 'Open the code-pet pane',
175    })
176    await setPet($, () => feel('happy', GREETINGS[timeOfDay()], 0))
177    settleLater($)
178    const opened = await $.ui.open({ id: PANE, title: 'Pet', rows: PANE_ROWS })
179    if (!opened.isPlaced) $.ui.toast('code-pet: window too narrow to open on its own — run /pet to open it')
180
181    return next(e)
182  })
183
184  on('command.run', { command: 'pet' }, async $ => {
185    await $.ui.open({ id: PANE, title: 'Pet', focus: true, rows: PANE_ROWS })
186
187    return { text: 'Pet pane opened.' }
188  })
189
190  on('turn.start', async ($, e, next) => {
191    const s = await setPet($, s => (s.mood === 'sleepy' ? s : feel('excited', 'ears up! let\'s see...', s.streak)))
192    settleLater($)
193    void think($, s.mood, 'the human just sent a new message')
194
195    return next(e)
196  })
197
198  on('tool.call', async ($, e, next) => {
199    const label = String(e.tool).replace(/^mcp__[^_]+__/, '')
200    let stillRunning = true
201    const slowTimer = $.clock.after(SLOW_CALL_MS, () => {
202      if (stillRunning) void setPet($, s => feel('sleepy', `watching ${label}... *tail swish*`, s.streak))
203    })
204
205    const ran = await next(e)
206    stillRunning = false
207    slowTimer.cancel()
208
209    if (ran.deny !== undefined) return ran
210
211    const hasFailed = ran.isError === true
212    const s = await setPet($, s => {
213      if (hasFailed) return feel('concerned', `hiss... ${label} didn't go well`, 0)
214      const streak = s.streak + 1
215      return streak >= 3
216        ? feel('excited', `zoomies! (${streak} in a row)`, streak)
217        : feel('happy', `purr~ ${label} worked`, streak)
218    })
219    settleLater($)
220    // Only the tool's name and outcome go to Haiku, never its input or output.
221    void think(
222      $,
223      s.mood,
224      hasFailed ? `the ${label} tool failed` : `the ${label} tool worked, ${s.streak} successes in a row`,
225    )
226
227    return ran
228  })
229
230  on('turn.complete', async ($, e, next) => {
231    const done = await next(e)
232    if (!e.agentId && !e.isAborted && e.reason === 'answer' && e.answer.trim()) void suggest($, e.answer)
233
234    return done
235  })
236
237  on('ui.render', { component: 'Pane', requestId: PANE }, async ($, e) => {
238    const { Box, Text, Button } = $.ui.resolve(e)
239    const state = await read($, pet)
240    const color = COLORS[state.mood]
241
242    return (
243      <Box
244        flexDirection="column"
245        alignItems="center"
246        flexGrow={1}
247        paddingX={1}
248      >
249        <Text color={color}>{SPARKLES[state.mood]}</Text>
250        <Box flexGrow={1} alignItems="center" justifyContent="center">
251          <Button key="face" plain label={FACES[state.mood]} hover={{ scope: 'face', color }} onPress={() => void pat($)} />
252        </Box>
253        <Text italic color={color} wrap="wrap">
254          {state.thought}
255        </Text>
256        {state.streak > 0 ? <Text dimColor>{`♥ ×${state.streak}`}</Text> : null}
257        <Box flexDirection="row">
258          <Button key="pat" plain hotkey="p" label="pat" onPress={() => void pat($)} />
259          <Text>{'   '}</Text>
260          <Button key="treat" plain hotkey="t" label="treat" onPress={() => void treat($)} />
261        </Box>
262      </Box>
263    )
264  })
265}
266

1export type Mood = 'neutral' | 'happy' | 'excited' | 'concerned' | 'sleepy' | 'loved'
2
3export type PetState = {
4  mood: Mood
5  thought: string
6  streak: number
7}
8
9declare module 'claude-code' {
10  interface PluginState {
11    'code-pet': { mood: PetState }
12  }
13}
14