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constant-time-analysis

Analyze cryptographic code to detect operations that leak secret data through execution timing variations.

Quality

72%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./skills/constant-time-analysis/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

81%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 strong, highly actionable skill body with executable commands, prerequisites, and an excellent false-positive verification workflow. The main weaknesses are redundancy in the language-specific Quick Start examples and a reference structure whose target files could not be verified in the provided bundle.

Suggestions

Consolidate the VM-compiled and Swift Quick Start subsections into the language-specific reference files to remove command examples that duplicate the main Quick Start.

Add a brief mention of ct_analyzer/analyzer.py's location and role alongside the references table so every referenced path is discoverable.

Trim the macOS PATH setup detail, which is already deferred to references/vm-compiled.md.

DimensionReasoningScore

Conciseness

The body is mostly tables and copy-paste commands, but the VM-compiled and Swift subsections re-run the same analyzer.py invocation already shown in Quick Start, and PATH/setup detail duplicates what is deferred to references/vm-compiled.md. Matches anchor 3 ('Mostly efficient but includes some unnecessary explanation or could be tightened') rather than 4 because of this repeated per-language redundancy.

3 / 5

Actionability

Fully executable guidance throughout: concrete commands with all flags (--warnings, --func, --json, --arch, --opt-level), a prerequisites table with install commands (e.g. 'dotnet tool install -g ilspycmd'), worked false-positive code examples, and a problem/detection/fix table. Matches anchor 5 ('Fully executable; copy-paste ready code or commands; specific examples cover the common cases').

5 / 5

Workflow Clarity

The process flows clearly from language selection and prerequisites through running the tool, interpreting PASSED/FAILED, and verifying results. The 'Verifying Results' section provides explicit validation with numbered steps ('Identify the secret inputs', 'Trace data flow'), a triage-question checklist, and true/false-positive classification — matching anchor 5 (explicit validation steps, feedback loops, checklists). This is read-only analysis, so the destructive/batch cap does not apply.

5 / 5

Progressive Disclosure

One-level-deep references are well-signaled via the Language Selection table (references/compiled.md, references/swift.md, etc.) with detailed setup correctly deferred to references/vm-compiled.md. Minor gaps keep it at anchor 4 rather than 5: the ct_analyzer/analyzer.py script is not covered by any reference listing, no bundle files were provided to verify the referenced paths exist, and some per-language Quick Start content overlaps what belongs in the language-specific reference files.

4 / 5

Total

17

/

20

Passed

Description

53%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.

The description states a clear, specific capability in a distinct niche, but has no trigger guidance and omits the natural vocabulary (timing attack, side-channel, constant-time) users would actually say. Its main gaps are the missing 'when' clause and thin keyword coverage.

Suggestions

Add an explicit trigger clause, e.g. "Use when the user writes or reviews cryptographic code, or mentions constant-time, side-channel, timing attacks, or KyberSlash."

Include the natural trigger vocabulary users would say — 'timing attack', 'side-channel', 'constant-time' — to improve keyword matching.

Optionally mention the breadth of capabilities (12 languages, cross-architecture testing, CI JSON output) to strengthen specificity beyond a single action.

DimensionReasoningScore

Specificity

"Analyze cryptographic code to detect operations that leak secret data" names the domain plus one concrete action (detecting timing-leaking operations), but stops there — no mention of triaging flags, per-language guidance, or fixes. This matches the anchor 'Names domain and 1-2 concrete actions, but not comprehensive'; it is above score 2 (more than a bare domain label) but below 4 (does not list several specific actions).

3 / 5

Completeness

The 'what' is clear ("detect operations that leak secret data through execution timing variations") but there is no 'Use when...' clause or equivalent trigger guidance, which caps completeness at 3 per the judging guidelines. Fits anchor 3 ('Has a clear what but when is missing or only weakly implied'), not 4, because no explicit when-guidance exists at all.

3 / 5

Trigger Term Quality

Keywords "cryptographic code" and "execution timing variations" are relevant, but the natural phrases users would say — "constant-time", "side-channel", "timing attack" — are absent even though the body lists them as triggers. Matches anchor 3 ('Some relevant keywords but missing common variations or synonyms'), not 4, since a user asking about a 'timing attack' would not obviously match this description.

3 / 5

Distinctiveness Conflict Risk

"Leak secret data through execution timing variations" carves a clear niche that is unlikely to fire for generic skills, but it could overlap with general security-review or code-audit skills. Sits between anchors 4 and 5 — mostly distinct with minor overlap risk with closely related security skills, so 4 rather than 5.

4 / 5

Total

13

/

20

Passed

Validation

87%

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

Validation — 14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

referenced_paths_exist

Referenced path issues: 13 missing

Warning

Total

14

/

16

Passed

Repository

administrakt0r/AI-Agents-Safe-Coding-Skills

Path

skills/constant-time-analysis/SKILL.md

Reviewed

Table of Contents

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