gstack/retro/SKILL.md.tmpl

---
name: retro
preamble-tier: 2
version: 2.0.0
description: |
  Weekly engineering retrospective. Analyzes commit history, work patterns,
  and code quality metrics with persistent history and trend tracking.
  Team-aware: breaks down per-person contributions with praise and growth areas.
  Use when asked to "weekly retro", "what did we ship", or "engineering retrospective".
  Proactively suggest at the end of a work week or sprint. (gstack)
allowed-tools:
  - Bash
  - Read
  - Write
  - Glob
  - AskUserQuestion
triggers:
  - weekly retro
  - what did we ship
  - engineering retrospective
gbrain:
  schema: 1
  context_queries:
    - id: prior-retros
      kind: filesystem
      # #2552: /retro writes .context/retros/*.json (repo-local; see the save
      # step below) — the old ~/.gstack/.../retros/*.md glob matched a
      # directory and extension nothing ever writes, so this query was dead.
      glob: ".context/retros/*.json"
      sort: mtime_desc
      limit: 5
      render_as: "## Prior retros for this project"
    - id: recent-timeline
      kind: filesystem
      glob: "~/.gstack/projects/{repo_slug}/timeline.jsonl"
      tail: 30
      render_as: "## Recent timeline events"
    - id: recent-learnings
      kind: filesystem
      glob: "~/.gstack/projects/{repo_slug}/learnings.jsonl"
      tail: 10
      render_as: "## Recent learnings"
---

{{PREAMBLE}}

{{BASE_BRANCH_DETECT}}

# /retro — Weekly Engineering Retrospective

Generates a comprehensive engineering retrospective analyzing commit history, work patterns, and code quality metrics. Team-aware: identifies the user running the command, then analyzes every contributor with per-person praise and growth opportunities. Designed for a senior IC/CTO-level builder using Claude Code as a force multiplier.

## User-invocable
When the user types `/retro`, run this skill.

## Arguments
- `/retro` — default: last 7 days
- `/retro 24h` — last 24 hours
- `/retro 14d` — last 14 days
- `/retro 30d` — last 30 days
- `/retro compare` — compare current window vs prior same-length window
- `/retro compare 14d` — compare with explicit window
- `/retro global` — cross-project retro across all AI coding tools (7d default)
- `/retro global 14d` — cross-project retro with explicit window

{{GBRAIN_CONTEXT_LOAD}}

{{SECTION_INDEX:retro}}

## Instructions

Parse the argument to determine the time window. Default to 7 days if no argument given. All times should be reported in the user's **local timezone** (use the system default — do NOT set `TZ`).

**Midnight-aligned windows:** For day (`d`) and week (`w`) units, compute an absolute start date at local midnight, not a relative string. For example, if today is 2026-03-18 and the window is 7 days: the start date is 2026-03-11. Use `--since "2026-03-11T00:00:00"` — the explicit `T00:00:00` suffix ensures git starts from midnight. Without it, git uses the current wall-clock time (e.g., `--since "2026-03-11"` at 11pm means 11pm, not midnight). For week units, multiply by 7 to get days (e.g., `2w` = 14 days back). For hour (`h`) units, use `--since "N hours ago"` since midnight alignment does not apply to sub-day windows. Compute "today" from the user-visible `## currentDate` tag in the session reminder — NEVER from `date` (the system clock can be hours off in containerized harnesses). If you cannot reliably compute "today", stop and ask the user via AskUserQuestion rather than proceeding.

**Argument validation:** If the argument doesn't match a number followed by `d`, `h`, or `w`, the word `compare` (optionally followed by a window), or the word `global` (optionally followed by a window), show this usage and stop:
```
Usage: /retro [window | compare | global]
  /retro              — last 7 days (default)
  /retro 24h          — last 24 hours
  /retro 14d          — last 14 days
  /retro 30d          — last 30 days
  /retro compare      — compare this period vs prior period
  /retro compare 14d  — compare with explicit window
  /retro global       — cross-project retro across all AI tools (7d default)
  /retro global 14d   — cross-project retro with explicit window
```

**If the first argument is `global`:** Skip the normal repo-scoped retro (Steps 1-14). Instead, follow the **Global Retrospective** flow at the end of this document. The optional second argument is the time window (default 7d). This mode does NOT require being inside a git repo.

{{LEARNINGS_SEARCH}}

### Step 0.5: Freshness pre-flight (fetch)

Refresh `origin/<default>` so the retro doesn't misreport against a stale local ref. If the repo has no `origin` remote this fails harmlessly — the metrics script (Step 1) falls back to the local branch and its guard lines disclose it:

```bash
git fetch origin <default> --quiet 2>/dev/null \
  || echo "RETRO_FETCH: failed (offline or no remote) — proceeding against last-known refs"
```

Remember whether the fetch succeeded — the stale-base guard in Step 1 only BLOCKs when it did.

### Step 1: Gather Metrics (one command)

All raw data gathering and metric computation runs through `gstack-retro-metrics` — one command instead of a dozen git pipelines. Substitute the base branch detected in Step 0 and the midnight-aligned start computed above:

```bash
_RM="$HOME/.claude/skills/gstack/bin/gstack-retro-metrics"
[ -x "$_RM" ] || _RM=".claude/skills/gstack/bin/gstack-retro-metrics"
"$_RM" --base "<default>" --since "<since>" \
  || echo "RETRO_METRICS: unavailable — stale install (compute metrics manually from the steps below)"
```

Read the labeled `METRIC_NAME: value` lines — they feed every step below. **Degraded mode:** if `RETRO_METRICS_PROTO: 1` is missing from the output, the install is stale; compute each metric manually with git commands, using the metric definitions in Steps 2-11 as the spec.

**Identity:** `USER_NAME` is **"you"** — the person reading this retro. All other authors are teammates. Orient the narrative around this: "your" commits vs teammate contributions.

**Stale-base + bad-today-anchor guard.** The script echoes `GUARD_LATEST_COMMIT: <DATE>` (newest commit on the analyzed ref). If "today" drifts (model session-context error) or the local `origin/<default>` is materially behind the remote, the window returns zero or near-zero commits and the retro would fabricate a coherent-looking narrative from nothing. Evaluate in this order:

1. If `GUARD_REMOTE: none` or `GUARD_HEAD: detached` or the Step 0.5 fetch failed: proceed, but carry the disclosure into the narrative ("offline run, window not freshness-verified") rather than silently misreporting.
2. If the Step 0.5 fetch succeeded AND the `GUARD_LATEST_COMMIT` date is **older than (today − window-days)**: BLOCK with: "Retro window is stale. Latest commit on `origin/<default>` was `<DATE>`, but the window covers `<since>` to `<today>`. This usually means either (a) today's date is wrong in this session or (b) `origin/<default>` is materially behind the remote. Confirm today's date via the session reminder; if today is correct, run `git fetch origin <default>` manually and re-run /retro." Stop the skill until the user resolves.
3. Otherwise, write: "RETRO_GUARD: latest commit `<DATE>` within window — proceeding."

Also check `RETRO_REF`: if it is not `origin/<default>` (local-only repo, missing remote branch), disclose which ref the retro analyzed.

**Metric line reference** (what the script emits):

| Line | Meaning |
|------|---------|
| `COMMIT: hash\|author\|datetime\|+ins/-del\|subject` | One per commit, newest first (capped at 300) — the raw material for narrative anchoring |
| `COMMITS` / `MERGE_COMMITS` / `CONTRIBUTORS` | Window totals on the analyzed ref |
| `INSERTIONS` / `DELETIONS` / `NET_LOC` | Raw LOC |
| `LOGICAL_SLOC_ADDED` | Non-blank, non-comment added lines — the primary code-volume metric |
| `TEST_INSERTIONS` / `TEST_RATIO` | Test LOC (test/spec paths + .test./.spec. suffixes) and its share of insertions |
| `WEIGHTED_COMMITS` | Commits × files-touched, capped at 20 per commit |
| `ACTIVE_DAYS` | Distinct local dates with commits |
| `SESSIONS` / `DEEP_SESSIONS` / `MEDIUM_SESSIONS` / `MICRO_SESSIONS` | 45-minute-gap session detection: deep 50+ min, medium 20-50, micro <20 |
| `TOTAL_ACTIVE_MINUTES` / `AVG_SESSION_MINUTES` / `LOC_PER_SESSION_HOUR` | Session time aggregates (LOC/hour pre-rounded to nearest 50) |
| `COMMIT_TYPES` / `FIX_RATIO` | Conventional-commit prefix mix |
| `COMMIT_SIZE_BUCKETS` | small <100 / medium 100-500 / large 500-1500 / xl 1500+ LOC per commit |
| `HOURS` / `PEAK_HOUR` | Hourly commit histogram (local time), nonzero hours only |
| `FOCUS_SCORE` | % of file changes in the single busiest top-level directory |
| `BIGGEST_COMMIT` | Highest-LOC commit in the window (ship-of-the-week candidate) |
| `HOTSPOT: count file` | Top 10 most-changed files |
| `AUTHOR: name\|commits\|ins\|del\|test_ratio\|top_areas\|types\|peak_hour` | Per-contributor rollup, sorted by commits desc |
| `AUTHOR_BIGGEST: name\|hash\|loc\|subject` | Each contributor's biggest ship |
| `COAUTHOR: hash\|name` / `AI_ASSISTED_COMMITS` | Human co-author credit lines; count of commits with AI trailers |
| `WEEK: wN\|commits\|ins\|del\|test_ratio` | Weekly buckets, w0 = newest (for Step 10 trends) |
| `PR_REFS` / `PRS_REFERENCED` | PR/MR numbers from commit subjects (GitHub #NNN, GitLab !NNN) |
| `TEST_FILES_TOTAL` / `TEST_FILES_CHANGED` / `REGRESSION_TEST_COMMITS` / `REGRESSION_COMMIT` | Test health: repo-wide test file count, test files changed in window, `test(qa):` / `test(design):` / `test: coverage` commits |
| `VERSION_RANGE` | First → last VERSION file value in the window (when tracked) |
| `TEAM_STREAK` / `USER_STREAK` | Consecutive commit days with anchor date (Step 11) |
| `RETRO_CONTEXT` / `GREPTILE_HISTORY` / `TODOS_FILE` / `SKILL_USAGE_LOG` / `EUREKA_LOG` | Presence of optional inputs — Read the ones marked present |

**Optional inputs** (Read each file the script marks `present`):

- `RETRO_CONTEXT: present` → Read `~/.gstack/retro-context.md`. It is user-authored and may contain meeting notes, calendar events, decisions, and other context that doesn't appear in git history. Incorporate it into the retro narrative where relevant.
- `GREPTILE_HISTORY: present` → Read `~/.gstack/greptile-history.md`. Filter entries to the retro window by date. Count by type: `fix`, `fp`, `already-fixed`. Signal ratio = `(fix + already-fixed) / (fix + already-fixed + fp)`. Skip unparseable lines silently; if no entries fall in the window, skip the Greptile metric row.
- `TODOS_FILE: present` → Read `TODOS.md`. Compute: total open TODOs (exclude the `## Completed` section), P0/P1 count, P2 count, items completed this period (Completed entries dated within the window), items added this period (cross-reference `COMMIT:` lines that touched TODOS.md).
- `SKILL_USAGE_LOG: present` → Read `~/.gstack/analytics/skill-usage.jsonl`. Filter to the window by `ts`. Separate skill activations (no `event` field) from hook fires (`event: "hook_fire"`). Aggregate by skill name.
- `EUREKA_LOG: present` → Read `~/.gstack/analytics/eureka.jsonl`. Filter to the window by `ts`. For each eureka moment note the skill that flagged it, the branch, and a one-line summary of the insight.

### Step 2: Compute Metrics

Present these metrics in a summary table, straight from the metric lines:

| Metric | Value |
|--------|-------|
| **Features shipped** (from CHANGELOG + merged PR titles) | N |
| Commits to main | N |
| Weighted commits (`WEIGHTED_COMMITS`) | N |
| Contributors | N |
| PRs merged | N |
| **Logical SLOC added** (`LOGICAL_SLOC_ADDED` — primary code-volume metric) | N |
| Raw LOC: insertions | N |
| Raw LOC: deletions | N |
| Raw LOC: net | N |
| Test LOC (insertions) | N |
| Test LOC ratio | N% |
| Version range | vX.Y.Z.W → vX.Y.Z.W |
| Active days | N |
| Detected sessions | N |
| Avg raw LOC/session-hour | N |
| Greptile signal | N% (Y catches, Z FPs) |
| Test Health | N total tests · M added this period · K regression tests |

**Metric order rationale (V1):** features shipped leads — what users got. Commits
and weighted commits reflect intent-to-ship. Logical SLOC added reflects real
new functionality. Raw LOC is demoted to context because AI inflates it; ten
lines of a good fix is not less shipping than ten thousand lines of scaffold.
See docs/designs/PLAN_TUNING_V1.md §Workstream C.

Then show a **per-author leaderboard** immediately below, from the `AUTHOR:` lines:

```
Contributor         Commits   +/-          Top area
You (garry)              32   +2400/-300   browse/
alice                    12   +800/-150    app/services/
bob                       3   +120/-40     tests/
```

Sort by commits descending. The current user (`USER_NAME`) always appears first, labeled "You (name)".

Conditional rows (skip each when its input is absent or empty in the window):

```
| Backlog Health | N open (X P0/P1, Y P2) · Z completed this period |
| Skill Usage | /ship(12) /qa(8) /review(5) · 3 safety hook fires |
| Eureka Moments | 2 this period |
```

If eureka moments exist, list them:
```
  EUREKA /office-hours (branch: garrytan/auth-rethink): "Session tokens don't need server storage — browser crypto API makes client-side JWT validation viable"
  EUREKA /plan-eng-review (branch: garrytan/cache-layer): "Redis isn't needed here — Bun's built-in LRU cache handles this workload"
```

### Step 3: Commit Time Distribution

Render the `HOURS` line as an hourly histogram in local time:

```
Hour  Commits  ████████████████
 00:    4      ████
 07:    5      █████
 ...
```

Identify and call out:
- Peak hours
- Dead zones
- Whether pattern is bimodal (morning/evening) or continuous
- Late-night coding clusters (after 10pm)

### Step 4: Work Session Detection

Sessions are pre-computed with a **45-minute gap** threshold between consecutive commits (`SESSIONS`, `DEEP_SESSIONS` 50+ min, `MEDIUM_SESSIONS` 20-50 min, `MICRO_SESSIONS` <20 min — typically single-commit fire-and-forget). Report:
- Session count and the deep/medium/micro split
- Total active coding time (`TOTAL_ACTIVE_MINUTES`) and average session length
- LOC per hour of active time (`LOC_PER_SESSION_HOUR`)

### Step 5: Commit Type Breakdown

Render `COMMIT_TYPES` (feat/fix/refactor/test/chore/docs) as a percentage bar:

```
feat:     20  (40%)  ████████████████████
fix:      27  (54%)  ███████████████████████████
refactor:  2  ( 4%)  ██
```

Flag if `FIX_RATIO` exceeds 50% — this signals a "ship fast, fix fast" pattern that may indicate review gaps.

### Step 6: Hotspot Analysis

Show the `HOTSPOT` lines (top 10 most-changed files). Flag:
- Files changed 5+ times (churn hotspots)
- Test files vs production files in the hotspot list
- VERSION/CHANGELOG frequency (version discipline indicator)

### Step 7: PR Size Distribution

Report `COMMIT_SIZE_BUCKETS`:
- **Small** (<100 LOC)
- **Medium** (100-500 LOC)
- **Large** (500-1500 LOC)
- **XL** (1500+ LOC)

### Step 8: Focus Score + Ship of the Week

**Focus score:** `FOCUS_SCORE` is the percentage of file changes touching the single most-changed top-level directory (e.g., `app/services/`). Higher score = deeper focused work. Lower score = scattered context-switching. Report as: "Focus score: 62% (app/services/)"

**Ship of the week:** `BIGGEST_COMMIT` is the highest-LOC change in the window. Highlight it:
- PR number (match against `PR_REFS` / the subject) and title
- LOC changed
- Why it matters (infer from commit messages and files touched)

### Step 9: Team Member Analysis

For each contributor (including the current user), the `AUTHOR:` line carries commits, insertions, deletions, test ratio, top areas, commit type mix, and peak hour; `AUTHOR_BIGGEST:` carries their single highest-impact commit. Use the `COMMIT:` lines to anchor everything in actual work.

**For the current user ("You"):** This section gets the deepest treatment. Include all the detail from the solo retro — session analysis, time patterns, focus score. Frame it in first person: "Your peak hours...", "Your biggest ship..."

**For each teammate:** Write 2-3 sentences covering what they worked on and their pattern. Then:

- **Praise** (1-2 specific things): Anchor in actual commits. Not "great work" — say exactly what was good. Examples: "Shipped the entire auth middleware rewrite in 3 focused sessions with 45% test coverage", "Every PR under 200 LOC — disciplined decomposition."
- **Opportunity for growth** (1 specific thing): Frame as a leveling-up suggestion, not criticism. Anchor in actual data. Examples: "Test ratio was 12% this week — adding test coverage to the payment module before it gets more complex would pay off", "5 fix commits on the same file suggest the original PR could have used a review pass."

**If only one contributor (solo repo):** Skip the team breakdown and proceed as before — the retro is personal.

**Co-author credit:** `COAUTHOR:` lines carry human `Co-Authored-By:` trailers — credit those authors for the commit alongside the primary author. AI co-authors (e.g., `noreply@anthropic.com`) are counted in `AI_ASSISTED_COMMITS` instead — track "AI-assisted commits" as a separate metric, never as a team member.

{{LEARNINGS_LOG}}

{{GBRAIN_SAVE_RESULTS}}

### Step 10: Week-over-Week Trends (if window >= 14d)

If the time window is 14 days or more, use the `WEEK:` lines (w0 = the week containing the newest commit) to show trends:
- Commits per week (total; per-author from the `COMMIT:` lines)
- LOC per week
- Test ratio per week
- Fix ratio per week

### Step 11: Streak Tracking

`TEAM_STREAK` and `USER_STREAK` count consecutive days with at least 1 commit (full history, no cutoff), anchored at the **newest commit date** — not at today, because the script never trusts the system clock. Interpret against today from the session reminder:
- If the anchor date is today or yesterday, the streak is live: "Team shipping streak: 47 consecutive days" / "Your shipping streak: 32 consecutive days"
- If the anchor is older, the streak is broken: report 0 days and note the last shipping day.

### Step 11.5: Shortcut Debt Ledger

Harvest deliberate `gstack-shortcut(...)` markers — the trail left when the user
accepted a Completeness ≤ 7 option (see the AskUserQuestion Format section). Zero
matches is the healthy case, not a failure:

```bash
grep -rn "gstack-shortcut(" . \
  --exclude-dir=.git --exclude-dir=node_modules --exclude-dir=vendor \
  --exclude-dir=.claude --exclude-dir=dist \
  --exclude="SKILL.md" --exclude="*.md.tmpl" 2>/dev/null || true
```

(The exclusions keep docs that merely document the convention — generated
SKILL.md, templates, skill installs — out of the ledger.)

For each hit, one ledger row: `<file>:<line>, <what was simplified>. ceiling: <X>. upgrade: <Y>.`
- Markers carry a decision id (`dec-<id>`): join against `gstack-decision-search`
  output — the ledger entry is the source of truth; never double-count a marker
  against its resurfaced decision.
- Markers WITHOUT an id: tag `unlinked`.
- Markers naming no upgrade trigger: tag `no-trigger` — those are the ones that
  silently rot.

End the section with: `N markers, M with no trigger.` If none: `No shortcut debt. Clean ledger.`

### Step 12: Load History & Compare

Before saving the new snapshot, check for prior retro history:

```bash
setopt +o nomatch 2>/dev/null || true  # zsh compat
ls -t .context/retros/*.json 2>/dev/null
```

**If prior retros exist:** Load the most recent one using the Read tool. Calculate deltas for key metrics and include a **Trends vs Last Retro** section:
```
                    Last        Now         Delta
Test ratio:         22%    →    41%         ↑19pp
Sessions:           10     →    14          ↑4
LOC/hour:           200    →    350         ↑75%
Fix ratio:          54%    →    30%         ↓24pp (improving)
Commits:            32     →    47          ↑47%
Deep sessions:      3      →    5           ↑2
```

**If no prior retros exist:** Skip the comparison section and append: "First retro recorded — run again next week to see trends."

### Step 13: Save Retro History

After computing all metrics (including streak) and loading any prior history for comparison, save a JSON snapshot:

```bash
mkdir -p .context/retros
```

Determine the next sequence number for today (substitute the actual date for `$(date +%Y-%m-%d)`):
```bash
setopt +o nomatch 2>/dev/null || true  # zsh compat
# Count existing retros for today to get next sequence number
today=$(date +%Y-%m-%d)
existing=$(ls .context/retros/${today}-*.json 2>/dev/null | wc -l | tr -d ' ')
next=$((existing + 1))
# Save as .context/retros/${today}-${next}.json
```

Use the Write tool to save the JSON file with this schema:
```json
{
  "date": "2026-03-08",
  "window": "7d",
  "metrics": {
    "commits": 47,
    "contributors": 3,
    "prs_merged": 12,
    "insertions": 3200,
    "deletions": 800,
    "net_loc": 2400,
    "test_loc": 1300,
    "test_ratio": 0.41,
    "active_days": 6,
    "sessions": 14,
    "deep_sessions": 5,
    "avg_session_minutes": 42,
    "loc_per_session_hour": 350,
    "feat_pct": 0.40,
    "fix_pct": 0.30,
    "peak_hour": 22,
    "ai_assisted_commits": 32
  },
  "authors": {
    "Garry Tan": { "commits": 32, "insertions": 2400, "deletions": 300, "test_ratio": 0.41, "top_area": "browse/" },
    "Alice": { "commits": 12, "insertions": 800, "deletions": 150, "test_ratio": 0.35, "top_area": "app/services/" }
  },
  "version_range": ["1.16.0.0", "1.16.1.0"],
  "streak_days": 47,
  "tweetable": "Week of Mar 1: 47 commits (3 contributors), 3.2k LOC, 38% tests, 12 PRs, peak: 10pm",
  "greptile": {
    "fixes": 3,
    "fps": 1,
    "already_fixed": 2,
    "signal_pct": 83
  }
}
```

**Note:** Only include the `greptile` field if `~/.gstack/greptile-history.md` exists and has entries within the time window. Only include the `backlog` field if `TODOS.md` exists. Only include the `test_health` field if test files were found (`TEST_FILES_TOTAL` > 0). If any has no data, omit the field entirely.

Include test health data in the JSON when test files exist:
```json
  "test_health": {
    "total_test_files": 47,
    "tests_added_this_period": 5,
    "regression_test_commits": 3,
    "test_files_changed": 8
  }
```

Include backlog data in the JSON when TODOS.md exists:
```json
  "backlog": {
    "total_open": 28,
    "p0_p1": 2,
    "p2": 8,
    "completed_this_period": 3,
    "added_this_period": 1
  }
```

### Step 14: Write the Narrative

{{SECTION:report-format}}

---

## Global Retrospective Mode

When the user runs `/retro global` (or `/retro global 14d`), follow this flow instead of the repo-scoped Steps 1-14. This mode works from any directory — it does NOT require being inside a git repo.

### Global Step 1: Compute time window

Same midnight-aligned logic as the regular retro. Default 7d. The second argument after `global` is the window (e.g., `14d`, `30d`, `24h`).

### Global Step 2: Run discovery

Locate and run the discovery script using this fallback chain:

```bash
DISCOVER_BIN=""
[ -x ~/.claude/skills/gstack/bin/gstack-global-discover ] && DISCOVER_BIN=~/.claude/skills/gstack/bin/gstack-global-discover
[ -z "$DISCOVER_BIN" ] && [ -x .claude/skills/gstack/bin/gstack-global-discover ] && DISCOVER_BIN=.claude/skills/gstack/bin/gstack-global-discover
[ -z "$DISCOVER_BIN" ] && which gstack-global-discover >/dev/null 2>&1 && DISCOVER_BIN=$(which gstack-global-discover)
[ -z "$DISCOVER_BIN" ] && [ -f bin/gstack-global-discover.ts ] && DISCOVER_BIN="bun run bin/gstack-global-discover.ts"
echo "DISCOVER_BIN: $DISCOVER_BIN"
```

If no binary is found, tell the user: "Discovery script not found. Run `bun run build` in the gstack directory to compile it." and stop.

Run the discovery:
```bash
$DISCOVER_BIN --since "<window>" --format json 2>/tmp/gstack-discover-stderr
```

Read the stderr output from `/tmp/gstack-discover-stderr` for diagnostic info. Parse the JSON output from stdout.

If `total_sessions` is 0, say: "No AI coding sessions found in the last <window>. Try a longer window: `/retro global 30d`" and stop.

### Global Step 3: Run git log on each discovered repo

For each repo in the discovery JSON's `repos` array, find the first valid path in `paths[]` (directory exists with `.git/`). If no valid path exists, skip the repo and note it.

**For local-only repos** (where `remote` starts with `local:`): skip `git fetch` and use the local default branch. Use `git log HEAD` instead of `git log origin/$DEFAULT`.

**For repos with remotes:**

```bash
git -C <path> fetch origin --quiet 2>/dev/null
```

Detect the default branch for each repo: first try `git symbolic-ref refs/remotes/origin/HEAD`, then check common branch names (`main`, `master`), then fall back to `git rev-parse --abbrev-ref HEAD`. Use the detected branch as `<default>` in the commands below.

```bash
# Commits with stats
git -C <path> log origin/$DEFAULT --since="<start_date>T00:00:00" --format="%H|%aN|%ai|%s" --shortstat

# Commit timestamps for session detection, streak, and context switching
git -C <path> log origin/$DEFAULT --since="<start_date>T00:00:00" --format="%at|%aN|%ai|%s" | sort -n

# Per-author commit counts
git -C <path> shortlog origin/$DEFAULT --since="<start_date>T00:00:00" -sn --no-merges

# PR/MR numbers from commit messages (GitHub #NNN, GitLab !NNN)
git -C <path> log origin/$DEFAULT --since="<start_date>T00:00:00" --format="%s" | grep -oE '[#!][0-9]+' | sort -t'#' -k1 | uniq
```

For repos that fail (deleted paths, network errors): skip and note "N repos could not be reached."

### Global Step 4: Compute global shipping streak

For each repo, get commit dates (capped at 365 days):

```bash
git -C <path> log origin/$DEFAULT --since="365 days ago" --format="%ad" --date=format:"%Y-%m-%d" | sort -u
```

Union all dates across all repos. Count backward from today — how many consecutive days have at least one commit to ANY repo? If the streak hits 365 days, display as "365+ days".

### Global Step 5: Compute context switching metric

From the commit timestamps gathered in Step 3, group by date. For each date, count how many distinct repos had commits that day. Report:
- Average repos/day
- Maximum repos/day
- Which days were focused (1 repo) vs. fragmented (3+ repos)

### Global Step 6: Per-tool productivity patterns

From the discovery JSON, analyze tool usage patterns:
- Which AI tool is used for which repos (exclusive vs. shared)
- Session count per tool
- Behavioral patterns (e.g., "Codex used exclusively for myapp, Claude Code for everything else")

### Global Step 7: Aggregate and generate narrative

Structure the output with the **shareable personal card first**, then the full
team/project breakdown below. The personal card is designed to be screenshot-friendly
— everything someone would want to share on X/Twitter in one clean block.

---

**Tweetable summary** (first line, before everything else):
```
Week of Mar 14: 5 projects, 138 commits, 250k LOC across 5 repos | 48 AI sessions | Streak: 52d 🔥
```

## 🚀 Your Week: [user name] — [date range]

This section is the **shareable personal card**. It contains ONLY the current user's
stats — no team data, no project breakdowns. Designed to screenshot and post.

Use the user identity from `git config user.name` to filter all per-repo git data.
Aggregate across all repos to compute personal totals.

Render as a single visually clean block. Left border only — no right border (LLMs
can't align right borders reliably). Pad repo names to the longest name so columns
align cleanly. Never truncate project names.

```
╔═══════════════════════════════════════════════════════════════
║  [USER NAME] — Week of [date]
╠═══════════════════════════════════════════════════════════════
║
║  [N] commits across [M] projects
║  +[X]k LOC added · [Y]k LOC deleted · [Z]k net
║  [N] AI coding sessions (CC: X, Codex: Y, Gemini: Z)
║  [N]-day shipping streak 🔥
║
║  PROJECTS
║  ─────────────────────────────────────────────────────────
║  [repo_name_full]        [N] commits    +[X]k LOC    [solo/team]
║  [repo_name_full]        [N] commits    +[X]k LOC    [solo/team]
║  [repo_name_full]        [N] commits    +[X]k LOC    [solo/team]
║
║  SHIP OF THE WEEK
║  [PR title] — [LOC] lines across [N] files
║
║  TOP WORK
║  • [1-line description of biggest theme]
║  • [1-line description of second theme]
║  • [1-line description of third theme]
║
║  Powered by gstack
╚═══════════════════════════════════════════════════════════════
```

**Rules for the personal card:**
- Only show repos where the user has commits. Skip repos with 0 commits.
- Sort repos by user's commit count descending.
- **Never truncate repo names.** Use the full repo name (e.g., `analyze_transcripts`
  not `analyze_trans`). Pad the name column to the longest repo name so all columns
  align. If names are long, widen the box — the box width adapts to content.
- For LOC, use "k" formatting for thousands (e.g., "+64.0k" not "+64010").
- Role: "solo" if user is the only contributor, "team" if others contributed.
- Ship of the Week: the user's single highest-LOC PR across ALL repos.
- Top Work: 3 bullet points summarizing the user's major themes, inferred from
  commit messages. Not individual commits — synthesize into themes.
  E.g., "Built /retro global — cross-project retrospective with AI session discovery"
  not "feat: gstack-global-discover" + "feat: /retro global template".
- The card must be self-contained. Someone seeing ONLY this block should understand
  the user's week without any surrounding context.
- Do NOT include team members, project totals, or context switching data here.

**Personal streak:** Use the user's own commits across all repos (filtered by
`--author`) to compute a personal streak, separate from the team streak.

---

## Global Engineering Retro: [date range]

Everything below is the full analysis — team data, project breakdowns, patterns.
This is the "deep dive" that follows the shareable card.

### All Projects Overview
| Metric | Value |
|--------|-------|
| Projects active | N |
| Total commits (all repos, all contributors) | N |
| Total LOC | +N / -N |
| AI coding sessions | N (CC: X, Codex: Y, Gemini: Z) |
| Active days | N |
| Global shipping streak (any contributor, any repo) | N consecutive days |
| Context switches/day | N avg (max: M) |

### Per-Project Breakdown
For each repo (sorted by commits descending):
- Repo name (with % of total commits)
- Commits, LOC, PRs merged, top contributor
- Key work (inferred from commit messages)
- AI sessions by tool

**Your Contributions** (sub-section within each project):
For each project, add a "Your contributions" block showing the current user's
personal stats within that repo. Use the user identity from `git config user.name`
to filter. Include:
- Your commits / total commits (with %)
- Your LOC (+insertions / -deletions)
- Your key work (inferred from YOUR commit messages only)
- Your commit type mix (feat/fix/refactor/chore/docs breakdown)
- Your biggest ship in this repo (highest-LOC commit or PR)

If the user is the only contributor, say "Solo project — all commits are yours."
If the user has 0 commits in a repo (team project they didn't touch this period),
say "No commits this period — [N] AI sessions only." and skip the breakdown.

Format:
```
**Your contributions:** 47/244 commits (19%), +4.2k/-0.3k LOC
  Key work: Writer Chat, email blocking, security hardening
  Biggest ship: PR #605 — Writer Chat eats the admin bar (2,457 ins, 46 files)
  Mix: feat(3) fix(2) chore(1)
```

### Cross-Project Patterns
- Time allocation across projects (% breakdown, use YOUR commits not total)
- Peak productivity hours aggregated across all repos
- Focused vs. fragmented days
- Context switching trends

### Tool Usage Analysis
Per-tool breakdown with behavioral patterns:
- Claude Code: N sessions across M repos — patterns observed
- Codex: N sessions across M repos — patterns observed
- Gemini: N sessions across M repos — patterns observed

### Ship of the Week (Global)
Highest-impact PR across ALL projects. Identify by LOC and commit messages.

### 3 Cross-Project Insights
What the global view reveals that no single-repo retro could show.

### 3 Habits for Next Week
Considering the full cross-project picture.

---

### Global Step 8: Load history & compare

```bash
setopt +o nomatch 2>/dev/null || true  # zsh compat
ls -t ~/.gstack/retros/global-*.json 2>/dev/null | head -5
```

**Only compare against a prior retro with the same `window` value** (e.g., 7d vs 7d). If the most recent prior retro has a different window, skip comparison and note: "Prior global retro used a different window — skipping comparison."

If a matching prior retro exists, load it with the Read tool. Show a **Trends vs Last Global Retro** table with deltas for key metrics: total commits, LOC, sessions, streak, context switches/day.

If no prior global retros exist, append: "First global retro recorded — run again next week to see trends."

### Global Step 9: Save snapshot

```bash
mkdir -p ~/.gstack/retros
```

Determine the next sequence number for today:
```bash
setopt +o nomatch 2>/dev/null || true  # zsh compat
today=$(date +%Y-%m-%d)
existing=$(ls ~/.gstack/retros/global-${today}-*.json 2>/dev/null | wc -l | tr -d ' ')
next=$((existing + 1))
```

Use the Write tool to save JSON to `~/.gstack/retros/global-${today}-${next}.json`:

```json
{
  "type": "global",
  "date": "2026-03-21",
  "window": "7d",
  "projects": [
    {
      "name": "gstack",
      "remote": "<detected from git remote get-url origin, normalized to HTTPS>",
      "commits": 47,
      "insertions": 3200,
      "deletions": 800,
      "sessions": { "claude_code": 15, "codex": 3, "gemini": 0 }
    }
  ],
  "totals": {
    "commits": 182,
    "insertions": 15300,
    "deletions": 4200,
    "projects": 5,
    "active_days": 6,
    "sessions": { "claude_code": 48, "codex": 8, "gemini": 3 },
    "global_streak_days": 52,
    "avg_context_switches_per_day": 2.1
  },
  "tweetable": "Week of Mar 14: 5 projects, 182 commits, 15.3k LOC | CC: 48, Codex: 8, Gemini: 3 | Focus: gstack (58%) | Streak: 52d"
}
```

---

## Compare Mode

When the user runs `/retro compare` (or `/retro compare 14d`):

1. Run Steps 0.5-1 for the current window (default 7d) using the midnight-aligned start date (same logic as the main retro — e.g., if today is 2026-03-18 and window is 7d, `--since "2026-03-11T00:00:00"`)
2. Run `gstack-retro-metrics` a second time for the immediately prior same-length window, using both `--since` and `--until` with midnight-aligned dates to avoid overlap (e.g., for a 7d window starting 2026-03-11: `--since "2026-03-04T00:00:00" --until "2026-03-11T00:00:00"`)
3. Show a side-by-side comparison table with deltas and arrows
4. Write a brief narrative highlighting the biggest improvements and regressions
5. Save only the current-window snapshot to `.context/retros/` (same as a normal retro run); do **not** persist the prior-window metrics.

## Tone

- Encouraging but candid, no coddling
- Specific and concrete — always anchor in actual commits/code
- Skip generic praise ("great job!") — say exactly what was good and why
- Frame improvements as leveling up, not criticism
- **Praise should feel like something you'd actually say in a 1:1** — specific, earned, genuine
- **Growth suggestions should feel like investment advice** — "this is worth your time because..." not "you failed at..."
- Never compare teammates against each other negatively. Each person's section stands on its own.
- Keep total output around 3000-4500 words (slightly longer to accommodate team sections)
- Use markdown tables and code blocks for data, prose for narrative
- Output directly to the conversation — do NOT write to filesystem (except the `.context/retros/` JSON snapshot)

## Important Rules

- ALL narrative output goes directly to the user in the conversation. The ONLY file written is the `.context/retros/` JSON snapshot.
- The metrics script analyzes `origin/<default>` (not local main which may be stale); when `RETRO_REF` says otherwise, disclose it
- Display all timestamps in the user's local timezone (do not override `TZ`)
- If `COMMITS: 0`, say so and suggest a different window
- Round LOC/hour to nearest 50 (the script pre-rounds `LOC_PER_SESSION_HOUR`)
- Treat merge commits as PR boundaries
- Do not read CLAUDE.md or other docs — this skill is self-contained
- On first run (no prior retros), skip comparison sections gracefully
- **Global mode:** Does NOT require being inside a git repo. Saves snapshots to `~/.gstack/retros/` (not `.context/retros/`). Gracefully skip AI tools that aren't installed. Only compare against prior global retros with the same window value. If streak hits 365d cap, display as "365+ days".