CtrlK
BlogDocsLog inGet started
Tessl Logo

testland/negative-test-generator

Generates negative / error-path test cases that mirror happy-path tests - for each happy-path test, produces companions exercising input validation rejection, missing required fields, type mismatches, authorization failures, rate-limit errors, and adversarial payloads from the malicious-payload-bank. Emits cases as parameterized tests in the project's runner format. Use when a feature has happy-path coverage but the rejection / error / unauthorized paths are untested.

97

Quality

97%

Does it follow best practices?

Impact

Average score across 3 eval scenarios

SecuritybySnyk

Passed

No findings from the security scan

Overview
Quality
Evals
Security
Files

Quality

Content

100%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.

The body is lean, executable, and well-structured: a complete worked example, concrete output format, an anti-pattern table, and a single well-signaled reference file. Validation feedback loops are present despite batch generation.

DimensionReasoningScore

Conciseness

Lean body that assumes Claude's competence — no padding explaining what tests, HTTP status codes, or libraries are; the category list and code examples each earn their tokens.

5 / 5

Actionability

Provides a fully executable, copy-paste-ready worked example with real pytest code, parametrize tables asserting specific status codes and structured error fields, plus a concrete output-format spec and an anti-pattern fix table.

5 / 5

Workflow Clarity

Sequences the work with a run → interpret → commit feedback loop ('Any failure indicates a real gap') and explicit handling of skipped categories; validation checkpoints are present for this batch-generating skill.

5 / 5

Progressive Disclosure

SKILL.md is a clear overview that points one level deep to the verified, well-signaled references/negative-path-catalog.md; detail is appropriately split rather than inlined.

5 / 5

Total

20

/

20

Passed

Description

92%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 is concrete, complete, and distinct: it enumerates the specific failure modes it generates, states the output format, and gives an explicit 'Use when' trigger. Its only minor gap is keyword synonym coverage.

DimensionReasoningScore

Specificity

Lists multiple concrete failure-mode actions (validation rejection, missing fields, type mismatches, auth failures, rate-limit, adversarial payloads) plus the emission format; comprehensive coverage rather than generic phrasing.

5 / 5

Completeness

Explicitly answers both 'what' (generates negative companions across listed categories, emits parameterized tests) and 'when' ('Use when a feature has happy-path coverage but the rejection / error / unauthorized paths are untested') with concrete trigger phrasing.

5 / 5

Trigger Term Quality

Natural terms like 'happy-path tests', 'error-path', 'rejection / error / unauthorized paths', and 'untested' are present, but a few common synonyms users might say (e.g. 'failing tests', 'edge cases') are missing.

4 / 5

Distinctiveness Conflict Risk

Occupies a clear niche (negative/error-path test generation) with a specific trigger condition; minimal conflict risk with sibling test skills, which are named but delineated.

5 / 5

Total

19

/

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.

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Reviewed

Table of Contents