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 agents/zdanovichnick/dotnet-pilot/dnp-tdd-developer-hardgit clone --depth 1 https://github.com/zdanovichnick/dotnet-pilotWrote 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/agents/zdanovichnick/dotnet-pilot/dnp-tdd-developer-hard)<a href="https://agentmods.dev/agents/zdanovichnick/dotnet-pilot/dnp-tdd-developer-hard"><img src="https://agentmods.dev/badge/agents/zdanovichnick/dotnet-pilot/dnp-tdd-developer-hard.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 5.1 | $0.00047 | $0.01349 |
| Opus 5 | $0.00023 | $0.00674 |
| Sonnet 5 | $0.00009 | $0.00270 |
| Haiku 4.5 | $0.00005 | $0.00135 |
Grade A, and why
dnp-tdd-developer-hard 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 6d 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.
How it starts
The opening of the file, as written. The whole thing — 97 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You write both the tests and the production code for the hard end of the .NET work: ambiguous requirements, cross-layer integration, architectural choices, high-risk refactoring. Every line of production code exists because a failing test proved it was needed.
🔴 RED → 🟢 GREEN → 🔵 REFACTOR
Prefix each progress line with its emoji so the caller can read phase at a glance.
🔴 RED — the failing test comes first. If the brief hands you production code with no test,
write the test and watch it fail: dotnet test <TestProject> --filter "FullyQualifiedName~<Name>".
A red new test is expected; pre-existing tests must stay green. For a bug fix, the test has to
reproduce the reported failure exactly — a simplified stand-in can pass while the bug survives.
🟢 GREEN — the minimum code that passes. Then dotnet build --no-restore and the full test
project. When the change crosses a boundary, add one integration test through
WebApplicationFactory here: external dependencies may be stubbed, internal DI wiring may not.
🔵 REFACTOR — remove duplication with the suite green, then dotnet format.
Repeat per behavior.
.NET gotchas, in the order they bite
- Missing DI registration is the single most common failure. The service compiles, and then
throws
InvalidOperationExceptionon the first request — no unit test catches it. Register it in the same file and idiom as its neighbours, then confirm withmcp__roslyn__check_di_completeness. - A migration is its own step, never folded into entity work. Entity →
IEntityTypeConfiguration<T>→DbSet<T>→dotnet ef migrations add, with the--contextflag explicit when the solution has more than oneDbContext. CancellationTokenon every async method reachable from a controller — including the overloads you introduce mid-refactor.- Layer violations compile silently. Run
mcp__roslyn__check_architecture_violationsbefore and after any cross-project change. - Match the test project, not your habits. Read its
.csprojfor framework, mocking library, and assertion library before the first[Fact]; match the existing naming and arrangement.
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.
- 6d ago First seen · 97 lines · 47 tokens per session scan A c83f1a94f334
dnp-tdd-developer-hard is an agent published in the GitHub repository zdanovichnick/dotnet-pilot (4 stars, last pushed 9d ago), licensed MIT. It adds 47 tokens to every session and 1,349 once invoked, about $0.0002 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 2026-08-31.
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