Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/stefanthecode/dotnet-ai-toolkit/test-coverage-gap-findernpx skills add StefanTheCode/dotnet-ai-toolkit --skill test-coverage-gap-findergit clone --depth 1 https://github.com/StefanTheCode/dotnet-ai-toolkitWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/stefanthecode/dotnet-ai-toolkit/test-coverage-gap-finder)<a href="https://agentmods.dev/skills/stefanthecode/dotnet-ai-toolkit/test-coverage-gap-finder"><img src="https://agentmods.dev/badge/skills/stefanthecode/dotnet-ai-toolkit/test-coverage-gap-finder.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00104 | $0.00618 |
| Opus 5 | $0.00052 | $0.00309 |
| Sonnet 5 | $0.00021 | $0.00124 |
| Haiku 4.5 | $0.00010 | $0.00062 |
Grade A, and why
test-coverage-gap-finder scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
Test Coverage Gap Finder
Find where tests are actually missing and prioritize by risk — so effort goes to the code that matters, not chasing a coverage percentage.
Input — point it at your project / coverage report
Works on a target: a project or GitHub URL, and optionally a coverage report (coverage.cobertura.xml, lcov). Map code vs tests:
grep -rln "public class\|public record" --include=*.cs <target> | grep -vi "Tests"
find <target> -iname "*Tests.cs" -o -iname "*.Tests.csproj"
# if a coverage file exists, parse it for low/zero-covered members
Generate coverage if asked: dotnet test --collect:"XPlat Code Coverage".
How it prioritizes (risk, not vanity %)
- Untested public types with real logic — services, handlers, domain methods, validators. High priority.
- Uncovered branches in covered classes — the
if/else/switch arms tests skip (where bugs hide). - Complex/critical code — payment, auth, calculations, state transitions — weighted up even if partly covered.
- Deprioritize — DTOs/POCOs, generated code, trivial getters: low value to test.
Output
## Coverage gaps (ranked)
🔴 <Type> — no tests; contains <business logic> → suggest: <key cases>
🟡 <Type.Method> — branch `<condition>` uncovered → add case
🟢 (skip) <DTOs / generated / trivial>
## Suggested next 5 tests
1. ... (hand off to xunit-test-generator)
Principles
- Coverage % is a vanity metric. 100% of trivial code is worthless; 60% covering all the risky branches is great.
- Prioritize by risk × complexity, not line count.
- A gap in a payment/auth path outranks ten gaps in DTOs.
- Don't recommend tests for code that can't meaningfully fail.
How to use it & best prompts
"What's not tested in this project", "where should I add tests next", "analyze my coverage report and prioritize", "find untested business logic". Hands off to xunit-test-generator and test-data-builder-generator.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 3d ago First seen · 45 lines · 104 tokens per session scan A 3afbd774bcd9
test-coverage-gap-finder is a skill published in the GitHub repository StefanTheCode/dotnet-ai-toolkit (19 stars, last pushed 25d ago), licensed MIT. It adds 104 tokens to every session and 618 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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