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+# PR4: Sentry `skip_sentry` Leak Fix + Dead `is_X_installed` Conjuncts Cleanup
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Ship two small audit cleanups in one PR:
+
+- **DES-4:** Add `"skip_sentry"` to `IGNORED_STRUCTLOG_ATTRIBUTES` so the flag stops leaking into Sentry's `contexts.structlog` when set to falsy (the function already suppresses the event for truthy values, but doesn't strip the field for falsy ones).
+- **DES-5:** Delete the dead `and import_checker.is_X_installed` conjuncts from four instruments' `is_ready()` methods. They're provably unreachable: `_register_or_skip` runs `check_dependencies()` before instantiating the instrument; if `check_dependencies()` returns False, `is_ready()` is never called.
+
+**Architecture:** Five files modified — four production deletions/additions and one test case. No new abstractions. No API changes.
+
+**Tech Stack:** Python 3.10+, pytest parametrized tests, sentry_sdk types.
+
+**Parent spec:** `docs/superpowers/specs/2026-05-31-audit-implementation-sequencing.md` (PR4 section).
+**Parent audit:** `docs/superpowers/specs/2026-05-31-bug-refactor-audit.md` (DES-4, DES-5).
+
+---
+
+## File Structure
+
+Four production files modified; one test file modified.
+
+- Modify: `lite_bootstrap/instruments/sentry_instrument.py` — add `"skip_sentry"` to `IGNORED_STRUCTLOG_ATTRIBUTES` (DES-4); drop dead conjunct from `SentryInstrument.is_ready()` (DES-5).
+- Modify: `lite_bootstrap/instruments/logging_instrument.py:139-140` — drop dead conjunct from `LoggingInstrument.is_ready()` (DES-5).
+- Modify: `lite_bootstrap/instruments/opentelemetry_instrument.py:82-86` — drop dead conjunct from `OpenTelemetryInstrument.is_ready()` (DES-5).
+- Modify: `lite_bootstrap/instruments/pyroscope_instrument.py:28-29` — drop dead conjunct from `PyroscopeInstrument.is_ready()` (DES-5).
+- Modify: `tests/instruments/test_sentry_instrument.py` — add parametrize case to `TestSentryEnrichEventFromStructlog::test_modify` covering the `skip_sentry=False` case.
+
+---
+
+## Locked decisions
+
+- **Bundling DES-4 + DES-5:** They're independent in scope but both trivial and both touch instrument files. Reviewing them together is cheaper than two PRs.
+- **DES-4 test placement:** Extend the existing `test_modify` parametrize block in `TestSentryEnrichEventFromStructlog`. Same shape as adjacent cases; no new test method.
+- **DES-5 testing:** No new tests. Pure dead-code deletion. The existing test suite already exercises the `is_ready()` paths via the framework integration tests; any breakage shows up there.
+
+---
+
+## Task 1: Create branch
+
+**Files:** (no files; git only)
+
+- [ ] **Step 1: Branch off `main`**
+
+```bash
+git checkout main
+git pull --ff-only origin main
+git checkout -b fix/des-4-5-small-cleanups
+```
+
+Expected: `Switched to a new branch 'fix/des-4-5-small-cleanups'`.
+
+If PR3 (`fix/crit-3-idempotent-teardown`) has not yet merged, that's fine — PR4 touches different files. Branch from current `main` regardless.
+
+---
+
+## Task 2: Add the failing regression test (DES-4)
+
+**File:** `tests/instruments/test_sentry_instrument.py`
+
+The file already has a class `TestSentryEnrichEventFromStructlog` with a parametrized `test_modify` method. Add a third case to its parametrize list that covers the `skip_sentry=False` scenario.
+
+- [ ] **Step 1: Add the new parametrize case**
+
+Current `test_modify` (around line 92 of the file) has two cases in its parametrize list. The list looks like:
+
+```python
+    @pytest.mark.parametrize(
+        ("event_before", "event_after"),
+        [
+            (
+                {"logentry": {"formatted": '{"event": "event name"}'}, "contexts": {}},
+                {"logentry": {"formatted": "event name"}, "contexts": {}},
+            ),
+            (
+                {
+                    "logentry": {
+                        "formatted": '{"event": "event name", "timestamp": 1, "level": "error", "logger": "event.logger", "tracing": {}, "foo": "bar"}'  # noqa: E501
+                    },
+                    "contexts": {},
+                },
+                {
+                    "logentry": {"formatted": "event name"},
+                    "contexts": {"structlog": {"foo": "bar"}},
+                },
+            ),
+        ],
+    )
+    def test_modify(self, event_before: "sentry_types.Event", event_after: "sentry_types.Event") -> None:
+        assert enrich_sentry_event_from_structlog_log(event_before, {}) == event_after
+```
+
+Add a third tuple to the parametrize list, after the existing two cases (preserving trailing comma in the list):
+
+```python
+            (
+                {
+                    "logentry": {
+                        "formatted": '{"event": "event name", "skip_sentry": false, "foo": "bar"}'
+                    },
+                    "contexts": {},
+                },
+                {
+                    "logentry": {"formatted": "event name"},
+                    "contexts": {"structlog": {"foo": "bar"}},
+                },
+            ),
+```
+
+The contract: when a structlog payload contains `skip_sentry=false` (a falsy value that doesn't trigger event suppression), the resulting `contexts.structlog` should contain `{"foo": "bar"}` only — `skip_sentry` should be stripped.
+
+- [ ] **Step 2: Run the test and verify it FAILS**
+
+```bash
+just test -- 'tests/instruments/test_sentry_instrument.py::TestSentryEnrichEventFromStructlog::test_modify' -v
+```
+
+Expected: one of the three parametrize cases (the new one) **FAILS** because the current `IGNORED_STRUCTLOG_ATTRIBUTES` set doesn't include `"skip_sentry"`. The actual `contexts.structlog` will be `{"skip_sentry": False, "foo": "bar"}`, which doesn't equal the expected `{"foo": "bar"}`. The other two cases should still PASS.
+
+If the new case passes, stop and investigate — either the assertion is wrong, or the bug isn't present.
+
+---
+
+## Task 3: Implement all changes
+
+Five small edits across four production files. Apply them all, run tests, lint, commit.
+
+### Fix 1 (DES-4): Strip `skip_sentry` from Sentry context
+
+- [ ] **Step 1: Add `"skip_sentry"` to `IGNORED_STRUCTLOG_ATTRIBUTES`**
+
+**File:** `lite_bootstrap/instruments/sentry_instrument.py:19-21`
+
+Current:
+
+```python
+IGNORED_STRUCTLOG_ATTRIBUTES: typing.Final = frozenset(
+    {"event", "level", "logger", "tracing", "timestamp", "exception"}
+)
+```
+
+Replace with:
+
+```python
+IGNORED_STRUCTLOG_ATTRIBUTES: typing.Final = frozenset(
+    {"event", "level", "logger", "tracing", "timestamp", "exception", "skip_sentry"}
+)
+```
+
+### Fix 2 (DES-5): Drop dead conjunct from `SentryInstrument.is_ready()`
+
+- [ ] **Step 2: Simplify `SentryInstrument.is_ready()`**
+
+**File:** `lite_bootstrap/instruments/sentry_instrument.py:100-101`
+
+Current:
+
+```python
+    def is_ready(self) -> bool:
+        return bool(self.bootstrap_config.sentry_dsn) and import_checker.is_sentry_installed
+```
+
+Replace with:
+
+```python
+    def is_ready(self) -> bool:
+        return bool(self.bootstrap_config.sentry_dsn)
+```
+
+### Fix 3 (DES-5): Drop dead conjunct from `LoggingInstrument.is_ready()`
+
+- [ ] **Step 3: Simplify `LoggingInstrument.is_ready()`**
+
+**File:** `lite_bootstrap/instruments/logging_instrument.py:139-140`
+
+Current:
+
+```python
+    def is_ready(self) -> bool:
+        return self.bootstrap_config.logging_enabled and import_checker.is_structlog_installed
+```
+
+Replace with:
+
+```python
+    def is_ready(self) -> bool:
+        return self.bootstrap_config.logging_enabled
+```
+
+### Fix 4 (DES-5): Drop dead conjunct from `OpenTelemetryInstrument.is_ready()`
+
+- [ ] **Step 4: Simplify `OpenTelemetryInstrument.is_ready()`**
+
+**File:** `lite_bootstrap/instruments/opentelemetry_instrument.py:82-86`
+
+Current:
+
+```python
+    def is_ready(self) -> bool:
+        return (
+            bool(self.bootstrap_config.opentelemetry_endpoint or self.bootstrap_config.opentelemetry_log_traces)
+            and import_checker.is_opentelemetry_installed
+        )
+```
+
+Replace with:
+
+```python
+    def is_ready(self) -> bool:
+        return bool(self.bootstrap_config.opentelemetry_endpoint or self.bootstrap_config.opentelemetry_log_traces)
+```
+
+### Fix 5 (DES-5): Drop dead conjunct from `PyroscopeInstrument.is_ready()`
+
+- [ ] **Step 5: Simplify `PyroscopeInstrument.is_ready()`**
+
+**File:** `lite_bootstrap/instruments/pyroscope_instrument.py:28-29`
+
+Current:
+
+```python
+    def is_ready(self) -> bool:
+        return bool(self.bootstrap_config.pyroscope_endpoint) and import_checker.is_pyroscope_installed
+```
+
+Replace with:
+
+```python
+    def is_ready(self) -> bool:
+        return bool(self.bootstrap_config.pyroscope_endpoint)
+```
+
+### Verify and commit
+
+- [ ] **Step 6: Run the previously-failing test, verify PASS**
+
+```bash
+just test -- 'tests/instruments/test_sentry_instrument.py::TestSentryEnrichEventFromStructlog' -v
+```
+
+Expected: all three `test_modify` cases PASS.
+
+- [ ] **Step 7: Run the full test suite**
+
+```bash
+just test
+```
+
+Expected: all tests PASS. The dead-conjunct deletions are provably no-ops at runtime (the `_register_or_skip` flow in `bootstrappers/base.py` checks `check_dependencies()` before any `is_ready()` call), so existing tests that exercise the missing-dependency path — e.g., `test_fastapi_bootstrapper_with_missing_instrument_dependency`, `test_litestar_bootstrapper_with_missing_instrument_dependency`, `test_free_bootstrapper_with_missing_instrument_dependency` — should still pass unchanged. If any of those fail, stop and investigate: the invariant we're relying on may not hold somewhere.
+
+- [ ] **Step 8: Run lint**
+
+```bash
+just lint
+```
+
+Expected: no errors. The four `import_checker` references being removed leave the import statement still used elsewhere in each file (e.g., `bootstrap()` methods), so no unused-import warnings should fire. Confirm.
+
+If a file ends up with `from lite_bootstrap import import_checker` no longer referenced anywhere, ruff `F401` will flag it. In that case, also remove the import. Most likely candidate is `pyroscope_instrument.py` (verify by reading the file).
+
+Actually, all four instrument files use `import_checker` in their `check_dependencies()` method as well, so the import will remain needed. Just confirm with `just lint`.
+
+- [ ] **Step 9: Commit (stage exactly 5 files)**
+
+```bash
+git add \
+  lite_bootstrap/instruments/sentry_instrument.py \
+  lite_bootstrap/instruments/logging_instrument.py \
+  lite_bootstrap/instruments/opentelemetry_instrument.py \
+  lite_bootstrap/instruments/pyroscope_instrument.py \
+  tests/instruments/test_sentry_instrument.py
+git commit -m "$(cat <<'EOF'
+fix: strip skip_sentry from Sentry context; drop dead is_X_installed conjuncts
+
+DES-4: enrich_sentry_event_from_structlog_log was already returning None
+(suppressing the event) when skip_sentry was truthy, but for falsy values
+(False, missing, "") the flag itself was not stripped from the structlog
+payload before it was attached to event["contexts"]["structlog"]. Add
+"skip_sentry" to IGNORED_STRUCTLOG_ATTRIBUTES so the field never leaks
+into Sentry context noise. Regression test added as a parametrize case
+on the existing test_modify.
+
+DES-5: each affected instrument's is_ready() returned `<config check> and
+import_checker.is_X_installed`. The conjunct is provably dead: BaseBootstrapper
+calls check_dependencies() in _register_or_skip before instantiating the
+instrument, and only invokes is_ready() if check_dependencies() returned True.
+Drop the redundant conjunct from SentryInstrument, LoggingInstrument,
+OpenTelemetryInstrument, and PyroscopeInstrument. Behavior is unchanged.
+
+Closes DES-4 and DES-5 from the audit.
+EOF
+)"
+```
+
+---
+
+## Task 4: Push and open PR
+
+**Files:** (no files; git push + gh)
+
+- [ ] **Step 1: Push the branch**
+
+```bash
+git push -u origin fix/des-4-5-small-cleanups
+```
+
+- [ ] **Step 2: Open the PR**
+
+```bash
+gh pr create --title "fix: strip skip_sentry from Sentry context; drop dead is_X_installed conjuncts" --body "$(cat <<'EOF'
+## Summary
+Two small audit cleanups bundled:
+
+- **DES-4 (Sentry):** \`skip_sentry\` was already triggering event suppression when truthy, but for falsy values (False/missing/"") the flag itself wasn't stripped from the structlog payload and ended up as noise in \`event["contexts"]["structlog"]\`. Add \`"skip_sentry"\` to \`IGNORED_STRUCTLOG_ATTRIBUTES\`. Regression test added as a parametrize case on the existing \`test_modify\`.
+- **DES-5 (dead conjuncts):** Four instruments' \`is_ready()\` methods ended with \`and import_checker.is_X_installed\`. That conjunct is provably unreachable — \`BaseBootstrapper._register_or_skip\` calls \`check_dependencies()\` first and only invokes \`is_ready()\` if it returned True. Behavior is unchanged. Cleanup makes the lifecycle easier to reason about.
+
+Closes DES-4 and DES-5 from an internal audit.
+
+## Test plan
+- [x] \`just test -- tests/instruments/test_sentry_instrument.py -v\` — pass.
+- [x] \`just test\` — full suite passes.
+- [x] \`just lint\` — clean (no unused-import warnings from the conjunct removals).
+- [ ] Reviewer: confirm the invariant claim — that \`is_ready()\` is only called after \`check_dependencies()\` has returned True — by reading \`bootstrappers/base.py:44-64\`.
+
+🤖 Generated with [Claude Code](https://claude.com/claude-code)
+EOF
+)"
+```
+
+---
+
+## Self-Review
+
+**Spec coverage check** against the sequencing spec (PR4 section) and audit (DES-4, DES-5):
+
+| Spec item | Task |
+|-----------|------|
+| Add `"skip_sentry"` to `IGNORED_STRUCTLOG_ATTRIBUTES` | Task 3, Step 1 |
+| Regression test asserting `skip_sentry` doesn't appear in context | Task 2, Step 1 |
+| Delete dead conjunct from `SentryInstrument.is_ready()` | Task 3, Step 2 |
+| Delete dead conjunct from `LoggingInstrument.is_ready()` | Task 3, Step 3 |
+| Delete dead conjunct from `OpenTelemetryInstrument.is_ready()` | Task 3, Step 4 |
+| Delete dead conjunct from `PyroscopeInstrument.is_ready()` | Task 3, Step 5 |
+| Branch name `fix/des-4-5-small-cleanups` | Task 1, Step 1 |
+| Verification: `just test` + `just lint` pass | Task 3, Steps 7-8 |
+
+All spec items covered. No placeholders. Parametrize-case shape matches adjacent cases byte-for-byte except for the payload values.
+
+**Deferred:**
+- Documenting the lifecycle invariant on `BaseInstrument` (mentioned as "optional" in the sequencing spec) — skip for now to keep the PR focused. Worth noting somewhere later (a `CONTRIBUTING.md`, or class docstrings as part of REF-3).