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/int2t05/engineering-skills/specnpx skills add int2t05/engineering-skills --skill specgit clone --depth 1 https://github.com/int2t05/engineering-skillsWrote 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/int2t05/engineering-skills/spec)<a href="https://agentmods.dev/skills/int2t05/engineering-skills/spec"><img src="https://agentmods.dev/badge/skills/int2t05/engineering-skills/spec.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 | $0.00085 | $0.01330 |
| Opus 5 | $0.00043 | $0.00665 |
| Sonnet 5 | $0.00017 | $0.00266 |
| Haiku 4.5 | $0.00009 | $0.00133 |
Grade A, and why
spec 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 4d 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 — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Spec
Write a structured specification before any code. The spec is the shared source of truth — it defines what we're building, why, and how we'll know it's done. Code without a spec is guessing.
When to use
- Starting a new project, feature, or significant change.
- Requirements are ambiguous or only exist as a vague idea.
- The change touches multiple files or modules.
- User says "write spec", "create prd", "spec out", "to spec", "写需求文档", "写规格", or "需求文档".
Not for: single-line fixes, typos, or changes where requirements are unambiguous; changes needing design decisions only — use architecture for system design.
Steps
-
Surface assumptions. Before writing any spec content, list what you're assuming (tech stack, auth model, database, target environment). Ask the user to correct before proceeding. Don't silently fill ambiguous requirements.
-
Ask 3–5 clarifying questions where the prompt is ambiguous — problem/goal, core functionality, scope, success criteria. Offer lettered options (A/B/C/D) so the user can respond "1A, 2C, 3B" for quick iteration. Only ask what's actually ambiguous. If the conversation already resolved the ambiguities, skip questions and synthesize directly.
-
Write the spec using the template below. Reframe vague requirements as testable success criteria ("make the dashboard faster" → "LCP < 2.5s on 4G; initial load < 500ms"). For PRD structure, user-story format, Given/When/Then acceptance criteria, and INVEST — load
references/prd-patterns.md. For success-criteria frameworks (North Star, AARRR, retention, A/B testing) — loadreferences/metrics-frameworks.md. For feature prioritization (RICE, Kano, MoSCoW) — loadreferences/prioritization.md. -
Publish. Two layers:
docs/PRD.md— project-level requirements, concise (mermaid-heavy), on main. The shared source of truth for the whole project.docs/vX.Y/prd.md— the current version's detailed PRD (user stories, full acceptance criteria, rules, boundaries), on the version branch. Falls back todocs/PRD.mdalone for single-version projects. Commit both — they are living documents. Update when decisions or scope change; reference in PRs.
What ships with it
4 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.
- 4d ago First seen · 106 lines · 85 tokens per session scan A 7bf5f62d853f
spec is a skill published in the GitHub repository int2t05/engineering-skills (3 stars, last pushed 3d ago), licensed MIT. It adds 85 tokens to every session and 1,330 once invoked, about $0.0004 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.
Other skills, from other repositories
specify-incremental
Decompose a single-feature specification into a linear, phase-by-phase implementation plan. Use this for medium-complexity work — single feature, one or two components — where transparent human-in-the-loop phase review is preferred over factory automation.
building
Implementation skill for writing production code with TDD. Covers the RED-GREEN-REFACTOR cycle, false-RED detection, vertical slicing, scope escalation, test process discipline, and code generation patterns. Loaded by component-builder and bug-investigator.
threat-model
Usar para modelar amenazas con metodología STRIDE. También: análisis de amenazas, STRIDE, superficie de ataque, vectores de ataque, modelado de amenazas.
writing-plans
Use when you have a spec or requirements for a multi-step task, before touching code.
sbom-generate
Usar para generar Software Bill of Materials para cumplimiento del CRA. También: Software Bill of Materials, inventario de componentes, CycloneDX, SPDX, cadena de suministro.
memory
This skill should be used when the user asks to record a design decision, search past project decisions, inspect the Alfred memory timeline, or work with the alfred-memory MCP server. Use it to call the namespaced MCP tools instead of inventing history.