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 wahidyankf/ose-public --skill developing-applicationsgit clone --depth 1 https://github.com/wahidyankf/ose-publicWrote 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/wahidyankf/ose-public/developing-applications)<a href="https://agentmods.dev/skills/wahidyankf/ose-public/developing-applications"><img src="https://agentmods.dev/badge/skills/wahidyankf/ose-public/developing-applications/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/wahidyankf/ose-public/developing-applications"><img src="https://agentmods.dev/badge/skills/wahidyankf/ose-public/developing-applications.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00048 | $0.01134 |
| Opus 5.5 | $0.00019 | $0.00454 |
| Sonnet 5.5 | $0.00010 | $0.00227 |
| Haiku 4.5 | $0.00005 | $0.00113 |
Grade A, and why
developing-applications 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 — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Developing Applications
The standards own the rules. Hexagonal Architecture and Functional Core, Imperative Shell place code; Test-Driven Development and Test Boundaries and Gates govern tests; Dependency Selection governs what is added; and Implementation Stages orders the work. A language's stack standard, such as TypeScript Standards, adds its own choices. This skill covers the judgement those rules leave to whoever writes the code.
Place Code Before Writing It
Ask of each new piece whether it decides or does. A decision belongs in the domain or functional core and receives everything it needs as a parameter. An effect belongs in an adapter or the shell. Coordinating a use case belongs in the application layer.
Misplacement shows early: a domain function that wants a clock, a connection, or a logger; an adapter holding a condition about a business rule; an application function choosing a transport status. Which layering fits a given application is decided in Application Shapes.
Give Every Error One Fate
At each call that can fail, choose exactly one:
| Fate | When |
|---|---|
| handle it here | this code can do something meaningful: retry, fall back, or tell the user |
| propagate it | the caller can decide, and this code adds context the caller lacks |
| fail loudly | the failure means a broken invariant or a programming error |
What ships with it
11 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.
- README.md 335 B
- reference/checker-regression-and-fixture-isolation.md 3.0 KB
- reference/checker-tdd-and-specs-completeness.md 2.9 KB
- reference/development-environment-setup.md 2.4 KB
- reference/git-workflow.md 3.2 KB
- reference/nx-monorepo-integration.md 2.8 KB
- reference/pre-commit-automation.md 2.6 KB
- reference/README.md 1.1 KB
- reference/reference-docs-and-tdd.md 3.4 KB
- reference/related-conventions.md 2.4 KB
- reference/tool-usage-and-workflow-pattern.md 1.8 KB
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 First seen · 91 lines · 48 tokens per session scan A 92f3d4cfff35
developing-applications is a skill published in the GitHub repository wahidyankf/ose-public (12 stars, last pushed today), licensed MIT. It adds 48 tokens to every session and 1,134 once invoked, about $0.0002 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 2026-10-14.
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