Monthly Development Journal

Generate a structured narrative of what happened in this project over a month. Reads git log, merged PRs, decisions, and any project memory the agent has access to.

Cadences

Default is monthly. Other cadences accept the same data but produce different narratives:

• /journal weekly — last 7 days. Lighter narrative; focus on what shipped + what's next.
• /journal sprint — last sprint length (default 14 days; configurable via .claude/journal-cadence.yaml).
• /journal release — since the last git tag. Releases-as-units narrative.
• /journal monthly (default) — calendar month, full retrospective.

The data-gathering steps (git log, PRs, decisions, memory) are identical; only the time window and narrative emphasis differ.

Step 1: Determine the Window

Resolve the time window by cadence:

Compute start_date and end_date accordingly. For monthly, start_date = first day of month, end_date = first day of next month. For weekly, ISO week boundaries. For sprint, today minus sprint length. For release, the tag's commit date and HEAD's commit date.

Check if the would-be filename (per Step 6's table) already exists. If so, ask: "A journal for {window-label} already exists. Regenerate it?"

Step 2: Gather Data

Run ALL of the following in parallel:

Git History

• git log --oneline --since="{start_date}" --until="{end_date}" — all commits
• git log --since="{start_date}" --until="{end_date}" --format="%H %s" --reverse — commits with hashes for grouping by branch
• git shortlog -sn --since="{start_date}" --until="{end_date}" — contributor summary
• Detect default branch: git symbolic-ref refs/remotes/origin/HEAD 2>/dev/null | sed 's|refs/remotes/origin/||' (fallback to main)

Merged PRs (if gh is available)

• gh pr list --state merged --limit 30 --json number,title,headRefName,mergedAt --jq '.[] | select(.mergedAt >= "{start_date}" and .mergedAt < "{end_date}")'

Releases

• git tag --sort=-creatordate --format="%(creatordate:short) %(refname:short)" — filter to tags within the month

Decisions

• Glob .claude/decisions/*.md (or your agent's equivalent) — read each, filter by date: frontmatter within the month

Memory

• If your agent has a project-memory directory, read its index for high-level context, and check filesystem mtime on individual entries to find anything created within the month.

Open Work

• gh pr list --state open --json number,title,headRefName,createdAt — open PRs
• git branch --no-merged {default-branch} --format="%(refname:short)" — unmerged branches

Step 3: Analyze and Group

Before writing the journal, process the raw data:

Group commits by branch/PR

• Match commits to merged PRs by branch name
• Commits not matching any PR get grouped under "Other work"
• For each group: count commits, count files changed, estimate lines

Spot patterns

Look for:

• Commit message prefixes (feat/fix/refactor/chore) — compute ratio
• Files modified in 3+ commits (hotspots)
• Same error pattern or bug type appearing multiple times
• Domains touched (group by first path segment)

Step 4: Generate the Journal

Write the following structure:

# {Month Name Year} — {project-name}

## What We Built

### {PR title or branch name}
{One-sentence summary derived from commit messages}
- {N} commits, {M} files changed
- Key changes: {2-3 most significant commits}

### {next group}
...

## What We Shipped
- {version} ({date}) — {tag or release title}

## What We Learned
- {From memory entries created this month — bullet per entry}
- {From decision reasoning — what was non-obvious}

## Decisions
- **{decision title}** ({date}) — {one-line why}
  Tripwire: {tripwire}

## Activity
- {N} sessions across {M} days
- Most active branches: {top 3}
- Commit breakdown: {X} feat, {Y} fix, {Z} refactor, {W} chore

## Patterns
- {Hotspot files — modified most often}
- {Recurring themes in commit messages or bug fixes}
- {Any observation worth noting}

## Looking Ahead
- {Open PRs with age}
- {Unmerged branches}
- {Anything flagged in commit messages as TODO or pending}

Omit any section that has zero content. Don't generate empty sections.

Step 4.5: Sentiment + velocity tracking

While scanning, surface signals beyond the raw what-happened:

• Velocity: commits per day, ratio vs prior period. Flag a 50%+ drop or rise.
• Crunch indicators: late-night commits (after 22:00 local), weekend commits in projects that don't normally see them, commit-message tone shift toward "fix"/"hotfix"/"revert" prefixes.
• Demoralization signals: long branches that never merge, repeated reverts, decision tripwires firing without acknowledgment.

Present these in a separate "Signals" section of the journal — factual, no judgment. The user reads and acts.

Step 4.75: Multi-model synthesis (optional)

For high-effort journals (monthly, release), optionally compose multi-model-synth: give the same gathered data to 2-3 models, compare narratives, synthesize the strongest. Different models emphasize different things — one might catch the velocity dip, another the architectural drift. Synthesis preserves both.

Skip for weekly/sprint (cost > value at small windows).

Step 5: Present for Review

Show the full journal in the conversation. Ask:

"Here's the journal for {window-label}. Anything you'd like to add, change, or remove before I save it?"

Step 6: Save

Create the journal directory if needed:

mkdir -p "$(git rev-parse --show-toplevel)/.claude/journal"

Filename by cadence:

Confirm: "Journal saved to <path>."