session-journal

1import type { EngineInterface, Register } from 'claude-code'
2
3export type Entry = { at: number; project: string; prompt: string; files: string[]; seconds: number }
4
5const DAY_MS = 86_400_000
6const pad = (n: number) => String(n).padStart(2, '0')
7
8// Local calendar day, so "yesterday" means what the user thinks it means.
9export const dayKey = (ms: number) => {
10  const d = new Date(ms)
11  return `day:${d.getFullYear()}-${pad(d.getMonth() + 1)}-${pad(d.getDate())}`
12}
13
14// Monday's standup covers Friday onwards.
15export const standupDays = (ms: number) => (new Date(ms).getDay() === 1 ? 3 : 1)
16
17export function formatEntries(entries: readonly Entry[]): string {
18  if (entries.length === 0) return 'Nothing logged.'
19  let lastDay = ''
20  const lines: string[] = []
21  for (const entry of entries) {
22    const d = new Date(entry.at)
23    const day = d.toDateString()
24    if (day !== lastDay) lines.push(`\n${day}`)
25    lastDay = day
26    const files = entry.files.length ? ` (${entry.files.length} file${entry.files.length === 1 ? '' : 's'})` : ''
27    lines.push(`  ${pad(d.getHours())}:${pad(d.getMinutes())}  ${entry.project}  ${entry.prompt.split('\n')[0]!.slice(0, 90)}${files}`)
28  }
29  return lines.join('\n').trim()
30}
31
32async function entriesSince($: EngineInterface, days: number): Promise<Entry[]> {
33  const now = await $.clock.now()
34  const out: Entry[] = []
35  for (let back = days; back >= 0; back--) {
36    out.push(...(((await $.store.get(dayKey(now - back * DAY_MS))) as Entry[] | undefined) ?? []))
37  }
38  return out
39}
40
41export const register: Register = (on, options) => {
42  const retentionMs = Number(options.retentionDays ?? 30) * DAY_MS
43  let current: { prompt: string; files: Set<string> } | undefined
44
45  on('session.start', async ($, e, next) => {
46    await $.command.register({ name: 'journal', description: 'Show what you worked on with Claude', argumentHint: '[days]' })
47    await $.command.register({ name: 'standup', description: 'Write a standup update from your journal', argumentHint: '[days]' })
48    const cutoff = dayKey((await $.clock.now()) - retentionMs)
49    for (const key of await $.store.keys()) {
50      if (key.startsWith('day:') && key < cutoff) await $.store.delete(key)
51    }
52    return next(e)
53  })
54
55  on('turn.start', async ($, e, next) => {
56    // A subagent's turn starts inside the main one; keep the main turn's prompt.
57    current ??= { prompt: e.text, files: new Set() }
58    return next(e)
59  })
60
61  on('tool.call', async ($, e, next) => {
62    const ran = await next(e)
63    const path = 'file_path' in e && ['Edit', 'Write'].includes(String(e.tool)) ? e.file_path : undefined
64    if (current && typeof path === 'string' && ran.deny === undefined && !ran.isError) current.files.add(path)
65    return ran
66  })
67
68  on('turn.complete', async ($, e, next) => {
69    const done = await next(e)
70    if (e.agentId !== undefined || !current) return done
71    const now = await $.clock.now()
72    const cwd = await $.session.cwd()
73    const entry: Entry = {
74      at: now,
75      project: cwd.split('/').filter(Boolean).pop() ?? cwd,
76      prompt: current.prompt.slice(0, 300),
77      files: [...current.files].slice(0, 20),
78      seconds: Math.round(e.durationMs / 1000),
79    }
80    current = undefined
81    const key = dayKey(now)
82    const day = ((await $.store.get(key)) as Entry[] | undefined) ?? []
83    // ponytail: read-modify-write; two sessions finishing in the same instant can drop one entry.
84    await $.store.set(key, [...day, entry].slice(-500))
85    return done
86  })
87
88  on('command.run', { command: 'journal' }, async ($, e) => {
89    const days = Math.max(0, Number.parseInt(e.args, 10) || 0)
90    return { text: formatEntries(await entriesSince($, days)) }
91  })
92
93  on('command.run', { command: 'standup' }, async ($, e) => {
94    const days = Number.parseInt(e.args, 10) || standupDays(await $.clock.now())
95    const entries = await entriesSince($, days)
96    if (entries.length === 0) return { text: 'Nothing in the journal to report yet.' }
97    const reply = await $.model.complete({
98      model: String(options.model ?? 'haiku'),
99      maxTokens: 800,
100      timeoutMs: 60_000,
101      system: 'You write concise engineering standup updates in plain text.',
102      prompt: `From this log of my coding-assistant sessions, write a standup update with three short sections: "Done", "In progress", "Blockers" (write "None" if nothing suggests one). Group by project, merge related prompts into one bullet, and describe outcomes rather than prompts. No preamble.\n\n${formatEntries(entries)}`,
103    })
104    return { text: reply.isAnswered ? reply.text : `Could not write the standup (${reply.reason}). Raw log:\n\n${formatEntries(entries)}` }
105  })
106}
107