Catalog Index

14 entries · as of 2026-09-19 · Status legend: stable · draft · deprecated

One file = one failure mode. Each entry is self-contained and safe to quote directly.

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A · Vacuous Verification

The check runs. It has no discriminating power.

ID	Entry	Symptom in one line	Status
SF-001	Zero items collected, exit 0	The suite is green because nothing ran	stable
SF-002	Early return as an implicit skip	The test body exits on a condition — invisibly	stable
SF-003	Swallowed exception	try/except: pass deletes the failure signal	stable
SF-004	Sentinel value on failure	A crash is indistinguishable from a bad result	stable

B · Uncounted Absence

Something required is missing, and missing does not count as failure.

ID	Entry	Symptom in one line	Status
SF-005	Neutral marker not counted	“Expected but absent” is logged, not counted	stable
SF-006	Undeclared means unchecked	The validator only checks what was declared	stable
SF-007	Empty value is silent	An empty required field breaks nothing	stable

C · Wrong Evidence

The signal used cannot prove the conclusion drawn from it.

ID	Entry	Symptom in one line	Status
SF-008	Loading artifact as evidence of use	A startup file proves loading, not use	stable
SF-009	Exposure counted as usage	Ambient presence inflates a usage metric	stable
SF-010	Local green is not remote green	Local gates pass, the published state differs	stable

D · Drifting Oracle

The check itself degrades.

ID	Entry	Symptom in one line	Status
SF-011	The always-green oracle	An exemption clause makes the check unconditional	stable
SF-012	Misattributed failure	It fails, but blames the wrong thing	stable

E · Process & Environment

The logic is correct. The environment lies to it.

ID	Entry	Symptom in one line	Status
SF-013	Stale copy contaminates the check	A backup inside the checked tree is read as input	stable
SF-014	Zombie process looks alive	A hung process reports nothing and never dies	stable

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Roadmap

Planned / welcome as contributions — see ../CONTRIBUTING.md:

• Clock and locale assumptions in oracles (timezone-shifted oracle)
• Time-based checks that silently skip on a date boundary
• Retry logic that converts a hard failure into a soft one
• Pagination truncation read as a complete result set
• Cache-hit read as a fresh verification
• Aggregation over an empty partition
• Idempotency checks that pass because the second run never executed

Adding an entry

cp TEMPLATE.md SF-<next>-<slug>.md
python ../tools/check-catalog.py     # must exit 0

Also update this file, the taxonomy table in ../README.md, and ../CHANGELOG.md — in the same commit.