feat: test coverage catalog + failure triage (merged branches) (#285)

* feat: add bin/gstack-repo-mode — solo vs collaborative detection with caching

Detects whether a repo is solo-dev (one person does 80%+ of recent commits)
or collaborative. Uses 90-day git shortlog window with 7-day cache in
~/.gstack/projects/{SLUG}/repo-mode.json. Config override via
`gstack-config set repo_mode solo|collaborative` takes precedence over
the heuristic. Minimum 5 commits required to classify (otherwise unknown).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* feat: test failure ownership triage — see something say something

Adds two new preamble sections to all gstack skills:
- Repo Ownership Mode: explains solo vs collaborative behavior
- See Something, Say Something: proactive issue flagging principle

Adds {{TEST_FAILURE_TRIAGE}} template variable (opt-in, used by /ship):
- Classifies test failures as in-branch vs pre-existing
- Solo mode defaults to "investigate and fix now"
- Collaborative mode offers "blame + assign GitHub issue" option
- Also offers P0 TODO and skip options

/ship Step 3 now triages test failures instead of hard-stopping on all
failures. In-branch failures still block shipping. Pre-existing failures
get user-directed triage based on repo mode.

Adds P2 TODO for gstack notes system (deferred lightweight reminder).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* chore: regenerate SKILL.md files for Claude and Codex hosts

All 22 Claude skills and 21 Codex skills regenerated with new preamble
sections (Repo Ownership Mode, See Something Say Something) and
{{TEST_FAILURE_TRIAGE}} resolved in ship/SKILL.md.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: validate repo mode values to prevent shell injection

Codex adversarial review found that unvalidated config/cache values
could be injected into shell via source <(gstack-repo-mode). Added
validate_mode() that only allows solo|collaborative|unknown — anything
else becomes "unknown". Prevents persistent code execution through
malicious config.yaml or tampered cache JSON.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: shell injection via branch names + feature-branch sampling bias

Codex code review found two issues:

P1: eval $(gstack-slug) in gstack-repo-mode executes branch names as
shell. Branch names like foo$(touch${IFS}pwned) are valid git refs and
would execute arbitrary commands. Fix: compute SLUG directly with sed
instead of eval'ing gstack-slug output.

P2: git shortlog HEAD only sees current branch history. On feature
branches that haven't merged main recently, other contributors disappear
from the sample. Fix: use git shortlog on the default branch
(origin/main) instead of HEAD.

Also improved blame lookup in collaborative triage to check both the
test file and the production code it covers.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: broaden codex-host stripping test to accommodate triage section

"Investigate and fix" now appears in TEST_FAILURE_TRIAGE (not just the
Codex review step). Use CODEX_REVIEWS config string as a more specific
marker for detecting the Codex review step in Codex-hosted skills.

* fix: replace template placeholder in TODOS.md with readable text

{{TEST_FAILURE_TRIAGE}} is template syntax but TODOS.md is not processed
by gen-skill-docs — replaced with human-readable reference.

* chore: bump version and changelog (v0.9.5.0)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* docs: add bin/ directory to project structure in CLAUDE.md

* test: add triage resolver unit tests, plan-eng coverage audit E2E, and triage E2E

- TEST_FAILURE_TRIAGE resolver: 6 unit tests verifying all triage steps (T1-T4),
  REPO_MODE branching, and safety default for ambiguous failures
- plan-eng-coverage-audit E2E: tests /plan-eng-review coverage audit codepath
  (gap identified during eng review — existed on neither branch)
- ship-triage E2E: planted-bug fixture with in-branch (truncate null) and
  pre-existing (divide-by-zero) failures; verifies correct classification
- Touchfile entries for diff-based test selection

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* chore: regenerate stale Codex SKILL.md for retro

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.agents/skills/gstack-browse/SKILL.md

@@ -25,6 +25,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -125,6 +127,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-design-consultation/SKILL.md

@@ -26,6 +26,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -126,6 +128,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-design-review/SKILL.md

@@ -26,6 +26,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -126,6 +128,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-document-release/SKILL.md

@@ -24,6 +24,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -124,6 +126,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-investigate/SKILL.md

@@ -27,6 +27,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -127,6 +129,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-office-hours/SKILL.md

@@ -28,6 +28,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -128,6 +130,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-plan-ceo-review/SKILL.md

@@ -27,6 +27,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -127,6 +129,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-plan-design-review/SKILL.md

@@ -26,6 +26,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -126,6 +128,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-plan-eng-review/SKILL.md

@@ -25,6 +25,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -125,6 +127,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-qa-only/SKILL.md

@@ -24,6 +24,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -124,6 +126,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-qa/SKILL.md

@@ -27,6 +27,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -127,6 +129,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-retro/SKILL.md

@@ -24,6 +24,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -124,6 +126,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.
@@ -428,7 +442,7 @@ From commit diffs, estimate PR sizes and bucket them:
 - **Small** (<100 LOC)
 - **Medium** (100-500 LOC)
 - **Large** (500-1500 LOC)
-- **XL** (1500+ LOC) — flag these with file counts
+- **XL** (1500+ LOC)
 
 ### Step 8: Focus Score + Ship of the Week
 
@@ -620,14 +634,13 @@ Narrative interpreting what the team-wide patterns mean:
 
 Narrative covering:
 - Commit type mix and what it reveals
-- PR size discipline (are PRs staying small?)
+- PR size distribution and what it reveals about shipping cadence
 - Fix-chain detection (sequences of fix commits on the same subsystem)
 - Version bump discipline
 
 ### Code Quality Signals
 - Test LOC ratio trend
 - Hotspot analysis (are the same files churning?)
-- Any XL PRs that should have been split
 - Greptile signal ratio and trend (if history exists): "Greptile: X% signal (Y valid catches, Z false positives)"
 
 ### Test Health
@@ -666,7 +679,7 @@ For each teammate (sorted by commits descending), write a section:
   - "Fixed the N+1 query that was causing 2s load times on the dashboard"
 - **Opportunity for growth**: 1 specific, constructive suggestion. Frame as investment, not criticism. Examples:
   - "Test coverage on the payment module is at 8% — worth investing in before the next feature lands on top of it"
-  - "3 of the 5 PRs were 800+ LOC — breaking these up would catch issues earlier and make review easier"
+  - "Most commits land in a single burst — spacing work across the day could reduce context-switching fatigue"
   - "All commits land between 1-4am — sustainable pace matters for code quality long-term"
 
 **AI collaboration note:** If many commits have `Co-Authored-By` AI trailers (e.g., Claude, Copilot), note the AI-assisted commit percentage as a team metric. Frame it neutrally — "N% of commits were AI-assisted" — without judgment.

.agents/skills/gstack-review/SKILL.md

@@ -23,6 +23,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -123,6 +125,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-setup-browser-cookies/SKILL.md

@@ -23,6 +23,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -123,6 +125,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.

.agents/skills/gstack-ship/SKILL.md

@@ -21,6 +21,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -121,6 +123,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.
@@ -237,7 +251,7 @@ You are running the `/ship` workflow. This is a **non-interactive, fully automat
 **Only stop for:**
 - On the base branch (abort)
 - Merge conflicts that can't be auto-resolved (stop, show conflicts)
-- Test failures (stop, show failures)
+- In-branch test failures (pre-existing failures are triaged, not auto-blocking)
 - Pre-landing review finds ASK items that need user judgment
 - MINOR or MAJOR version bump needed (ask — see Step 4)
 - Greptile review comments that need user decision (complex fixes, false positives)
@@ -521,7 +535,105 @@ wait
 
 After both complete, read the output files and check pass/fail.
 
-**If any test fails:** Show the failures and **STOP**. Do not proceed.
+**If any test fails:** Do NOT immediately stop. Apply the Test Failure Ownership Triage:
+
+## Test Failure Ownership Triage
+
+When tests fail, do NOT immediately stop. First, determine ownership:
+
+### Step T1: Classify each failure
+
+For each failing test:
+
+1. **Get the files changed on this branch:**
+   ```bash
+   git diff origin/<base>...HEAD --name-only
+   ```
+
+2. **Classify the failure:**
+   - **In-branch** if: the failing test file itself was modified on this branch, OR the test output references code that was changed on this branch, OR you can trace the failure to a change in the branch diff.
+   - **Likely pre-existing** if: neither the test file nor the code it tests was modified on this branch, AND the failure is unrelated to any branch change you can identify.
+   - **When ambiguous, default to in-branch.** It is safer to stop the developer than to let a broken test ship. Only classify as pre-existing when you are confident.
+
+   This classification is heuristic — use your judgment reading the diff and the test output. You do not have a programmatic dependency graph.
+
+### Step T2: Handle in-branch failures
+
+**STOP.** These are your failures. Show them and do not proceed. The developer must fix their own broken tests before shipping.
+
+### Step T3: Handle pre-existing failures
+
+Check `REPO_MODE` from the preamble output.
+
+**If REPO_MODE is `solo`:**
+
+Use AskUserQuestion:
+
+> These test failures appear pre-existing (not caused by your branch changes):
+>
+> [list each failure with file:line and brief error description]
+>
+> Since this is a solo repo, you're the only one who will fix these.
+>
+> RECOMMENDATION: Choose A — fix now while the context is fresh. Completeness: 9/10.
+> A) Investigate and fix now (human: ~2-4h / CC: ~15min) — Completeness: 10/10
+> B) Add as P0 TODO — fix after this branch lands — Completeness: 7/10
+> C) Skip — I know about this, ship anyway — Completeness: 3/10
+
+**If REPO_MODE is `collaborative` or `unknown`:**
+
+Use AskUserQuestion:
+
+> These test failures appear pre-existing (not caused by your branch changes):
+>
+> [list each failure with file:line and brief error description]
+>
+> This is a collaborative repo — these may be someone else's responsibility.
+>
+> RECOMMENDATION: Choose B — assign it to whoever broke it so the right person fixes it. Completeness: 9/10.
+> A) Investigate and fix now anyway — Completeness: 10/10
+> B) Blame + assign GitHub issue to the author — Completeness: 9/10
+> C) Add as P0 TODO — Completeness: 7/10
+> D) Skip — ship anyway — Completeness: 3/10
+
+### Step T4: Execute the chosen action
+
+**If "Investigate and fix now":**
+- Switch to /investigate mindset: root cause first, then minimal fix.
+- Fix the pre-existing failure.
+- Commit the fix separately from the branch's changes: `git commit -m "fix: pre-existing test failure in <test-file>"`
+- Continue with the workflow.
+
+**If "Add as P0 TODO":**
+- If `TODOS.md` exists, add the entry following the format in `review/TODOS-format.md` (or `.agents/skills/gstack/review/TODOS-format.md`).
+- If `TODOS.md` does not exist, create it with the standard header and add the entry.
+- Entry should include: title, the error output, which branch it was noticed on, and priority P0.
+- Continue with the workflow — treat the pre-existing failure as non-blocking.
+
+**If "Blame + assign GitHub issue" (collaborative only):**
+- Find who likely broke it. Check BOTH the test file AND the production code it tests:
+  ```bash
+  # Who last touched the failing test?
+  git log --format="%an (%ae)" -1 -- <failing-test-file>
+  # Who last touched the production code the test covers? (often the actual breaker)
+  git log --format="%an (%ae)" -1 -- <source-file-under-test>
+  ```
+  If these are different people, prefer the production code author — they likely introduced the regression.
+- Create a GitHub issue assigned to that person:
+  ```bash
+  gh issue create \
+    --title "Pre-existing test failure: <test-name>" \
+    --body "Found failing on branch <current-branch>. Failure is pre-existing.\n\n**Error:**\n```\n<first 10 lines>\n```\n\n**Last modified by:** <author>\n**Noticed by:** gstack /ship on <date>" \
+    --assignee "<github-username>"
+  ```
+- If `gh` is not available or `--assignee` fails (user not in org, etc.), create the issue without assignee and note who should look at it in the body.
+- Continue with the workflow.
+
+**If "Skip":**
+- Continue with the workflow.
+- Note in output: "Pre-existing test failure skipped: <test-name>"
+
+**After triage:** If any in-branch failures remain unfixed, **STOP**. Do not proceed. If all failures were pre-existing and handled (fixed, TODOed, assigned, or skipped), continue to Step 3.25.
 
 **If all pass:** Continue silently — just note the counts briefly.
 

.agents/skills/gstack/SKILL.md

@@ -56,6 +56,8 @@ _PROACTIVE=$(~/.codex/skills/gstack/bin/gstack-config get proactive 2>/dev/null
 _BRANCH=$(git branch --show-current 2>/dev/null || echo "unknown")
 echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
+source <(~/.codex/skills/gstack/bin/gstack-repo-mode 2>/dev/null) || REPO_MODE=unknown
+echo "REPO_MODE: $REPO_MODE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
 _TEL=$(~/.codex/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
@@ -156,6 +158,18 @@ AI-assisted coding makes the marginal cost of completeness near-zero. When you p
 - BAD: "Let's defer test coverage to a follow-up PR." (Tests are the cheapest lake to boil.)
 - BAD: Quoting only human-team effort: "This would take 2 weeks." (Say: "2 weeks human / ~1 hour CC.")
 
+## Repo Ownership Mode — See Something, Say Something
+
+`REPO_MODE` from the preamble tells you who owns issues in this repo:
+
+- **`solo`** — One person does 80%+ of the work. They own everything. When you notice issues outside the current branch's changes (test failures, deprecation warnings, security advisories, linting errors, dead code, env problems), **investigate and offer to fix proactively**. The solo dev is the only person who will fix it. Default to action.
+- **`collaborative`** — Multiple active contributors. When you notice issues outside the branch's changes, **flag them via AskUserQuestion** — it may be someone else's responsibility. Default to asking, not fixing.
+- **`unknown`** — Treat as collaborative (safer default — ask before fixing).
+
+**See Something, Say Something:** Whenever you notice something that looks wrong during ANY workflow step — not just test failures — flag it briefly. One sentence: what you noticed and its impact. In solo mode, follow up with "Want me to fix it?" In collaborative mode, just flag it and move on.
+
+Never let a noticed issue silently pass. The whole point is proactive communication.
+
 ## Contributor Mode
 
 If `_CONTRIB` is `true`: you are in **contributor mode**. You're a gstack user who also helps make it better.