CtrlK
BlogDocsLog inGet started
Tessl Logo
SkillPublic

deadlock-detection-harness

Use when a service that takes two or more locks hangs in production with no error, or before a release when lock order across code paths was never checked. Records lock order, finds cycles, uses lock timeouts to fail instead of hang, and reads jstack or gdb thread dumps.

Quality

83%

Does it follow best practices?

Run evals on this skill

Adds up to 20 points to the overall score

View guide
SecuritybySnyk

Passed

No findings from the security scan

The canonical home for this skill is testland/deadlock-detection-harness

SKILL.md
Quality
Evals
Security

Quality

Content

75%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A well-structured, actionable testing harness with sequenced steps, working code, and honest limitations/anti-patterns sections. It consistently sits just below excellent due to small executability gaps, a few redundant explanatory lines, and a fully monolithic layout with no bundle separation.

DimensionReasoningScore

Conciseness

Efficient and terse overall, with only minor trimmable over-explanation of concepts Claude already knows ("A deadlock = a cycle in the lock-wait graph: thread A holds X waiting for Y...", "Fewer acquire sites = easier to reason about lock order").

4 / 5

Actionability

Mostly executable guidance with concrete code and commands (OrderedLock, build_lock_graph, TSAN_OPTIONS=detect_deadlocks=1, jstack/gdb commands), but minor gaps: Step 5 uses time.sleep without importing time, and Steps 4/8 rely on undefined run_workload() placeholders.

4 / 5

Workflow Clarity

Eight clearly numbered steps with per-step use-conditions and an anti-patterns table mapping failures to fixes, plus embedded test assertions as checkpoints; however, no explicit validate-then-fix-then-retry loop in the main flow keeps it below the top anchor.

4 / 5

Progressive Disclosure

Well-organized inline structure with clear section headers and a single one-level external reference (TSan docs link), nothing buried or nested; but all ~230 lines live in SKILL.md with no bundle files, where per-language detail could be split out.

4 / 5

Total

16

/

20

Passed

Description

83%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong description with explicit, concrete when-triggers and a clear third-person list of capabilities. Its main weakness is the omission of the word "deadlock" — the single most natural trigger term — and of sanitizer-based detection from the what-clause.

DimensionReasoningScore

Specificity

Lists several concrete actions ("Records lock order, finds cycles, uses lock timeouts to fail instead of hang, and reads jstack or gdb thread dumps") but omits TSan/sanitizer-based detection, a minor coverage gap that places it just below the comprehensive anchor.

4 / 5

Completeness

Explicitly answers both: two concrete trigger clauses ("Use when a service that takes two or more locks hangs in production with no error, or before a release when lock order across code paths was never checked") plus a clear multi-action what-statement.

5 / 5

Trigger Term Quality

Good natural keyword coverage ("hangs in production", "lock order", "jstack or gdb thread dumps"), but the most natural user term "deadlock" itself never appears, nor synonyms like "frozen" or "stuck".

4 / 5

Distinctiveness Conflict Risk

The lock-order/thread-dump niche is mostly distinct (jstack, gdb, locks), but "hangs in production with no error" has minor overlap risk with generic hang- or performance-debugging skills, and the absent "deadlock" keyword slightly weakens routing precision.

4 / 5

Total

17

/

20

Passed

Validation

100%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

testland/qa

Path

plugins/qa-concurrency/skills/deadlock-detection-harness/SKILL.md

Reviewed

Table of Contents

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.