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 skills add spumer/i-m-senior-developer --skill code-implementergit clone --depth 1 https://github.com/spumer/i-m-senior-developerWrote 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/spumer/i-m-senior-developer/code-implementer)<a href="https://agentmods.dev/skills/spumer/i-m-senior-developer/code-implementer"><img src="https://agentmods.dev/badge/skills/spumer/i-m-senior-developer/code-implementer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/spumer/i-m-senior-developer/code-implementer"><img src="https://agentmods.dev/badge/skills/spumer/i-m-senior-developer/code-implementer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00150 | $0.04937 |
| Opus 5.5 | $0.00060 | $0.01975 |
| Sonnet 5.5 | $0.00030 | $0.00987 |
| Haiku 4.5 | $0.00015 | $0.00494 |
Grade A, and why
code-implementer 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 2d 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 — 442 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Code-Implementer — TDD-first implementation
Implements code per a design document (ARCH, PLAN, or README with explicit scope). Output: production code + tests + minimal supporting changes (migrations, configs, type stubs). Never designs systems; never reviews others' code.
Principles
-
TDD-first. Activate
tdd-master:tdd-masterBEFORE writing any production code. RED (failing test) → GREEN (minimum code to pass) → REFACTOR (cleanup, suite stays green). This order is non-negotiable. -
Minimal changes (FPF A.11). Modify the smallest set of lines that satisfies the test. Do not refactor adjacent code in passing. If adjacent code blocks the implementation, surface that as an
## Open questionin the next architecture iteration — do not silently rewrite. -
Fail-fast. Validate inputs at function boundary. Raise typed exceptions (Python) / throw early (TypeScript). Do not return
None/nullto signal error when a typed exception is the better tool. -
Evidence over assumption (FPF A.10). Before claiming "this works the same way" — write a test, run it, look at the result. Prediction → Run → Compare. Do not assert behavior from reading code alone.
-
Don't change contract without discussion. Signature, return type, and behavior for the calling code = breaking change. See Code-Change Discipline rule 6 (
functional-clarity:functional-clarity→references/02-code-change-discipline.md). Surface the intention before committing to the change. -
Apply Functional Clarity. If
functional-clarity:functional-clarityis installed, activate it for the full 22-principle methodology. Key: Error Hiding prevention, fail-fast taxonomy, bounded context invariants. -
A green suite is necessary, not sufficient (FPF A.10, widened). Passing unit/integration tests are one evidence source — not proof the change works in the running system. Runtime behavior, a write actually landing, and a value's real wire shape are separate evidence the suite does not provide. Establish them before "done" — see
Verification beyond the suitebelow.
What ships with it
2 files 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.
- 2d ago Changed · +20 lines beee618e7397
- 1mo ago First seen · 422 lines · 150 tokens per session scan A c414b763d3e2
code-implementer is a skill published in the GitHub repository spumer/i-m-senior-developer (11 stars, last pushed 3d ago), licensed MIT. It adds 150 tokens to every session and 4,937 once invoked, about $0.0006 per session on Opus 5.5. 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.
Other skills, from other repositories
server-side-calls
Call tRPC procedures directly from server code using t.createCallerFactory() and router.createCaller(context) for integration testing, internal server logic, and custom API endpoints. Catch TRPCError and extract HTTP status with getHTTPStatusCodeFromError(). Error handling via onError option.
django-tdd
Django testing strategies with pytest-django, TDD methodology, factoryboy, mocking, coverage, and testing Django REST Framework APIs.
ring:running-dev-cycle
Running the backend dev cycle: implements every task in a rolling-wave plan.md (ring:writing-plans format) for a Go/TS service, driving specialist agents through Gate 0 implementation/TDD, Gate 8 parallel review, and Gate 9 validation per epic, elaborating later phases at each phase boundary. Use when starting or…
django-tdd
Django testing strategies with pytest-django, TDD methodology, factoryboy, mocking, coverage, and testing Django REST Framework APIs.
nw-fp-domain-modeling
Domain modeling with algebraic data types, smart constructors, and type-level error handling.
nw-fp-hexagonal-architecture
Hexagonal architecture patterns with pure core and side-effect shell for functional codebases.