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/guillemroca/agent-skills-android/spec-driven-developmentnpx skills add GuillemRoca/agent-skills-android --skill spec-driven-developmentgit clone --depth 1 https://github.com/GuillemRoca/agent-skills-androidWrote 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/guillemroca/agent-skills-android/spec-driven-development)<a href="https://agentmods.dev/skills/guillemroca/agent-skills-android/spec-driven-development"><img src="https://agentmods.dev/badge/skills/guillemroca/agent-skills-android/spec-driven-development.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 | $0.00041 | $0.00937 |
| Opus 5 | $0.00020 | $0.00468 |
| Sonnet 5 | $0.00008 | $0.00187 |
| Haiku 4.5 | $0.00004 | $0.00094 |
Grade A, and why
spec-driven-development 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 — 116 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Spec-Driven Development
Overview
Write a structured specification before writing code. The spec becomes the shared source of truth — a development contract that prevents misalignment, scope creep, and wasted effort. Every implementation decision traces back to the spec.
When to Use
- Starting a new Android project or module
- Adding a feature that spans multiple files or layers
- Requirements are ambiguous or come from multiple stakeholders
- Before writing a
tasks/plan.md
Skip when: Single-line fixes or changes that are unambiguous and self-contained.
Core Process
Phase 1: Specify
-
Ask clarifying questions before writing anything:
- What problem does this solve? Who is the user?
- Which features are in scope? Which are explicitly out?
- What is the tech stack? (minSdk, target SDK, Compose vs XML, DI framework)
- What are the boundaries? (offline support? accessibility? tablet?)
-
Write SPEC.md with these sections:
# Feature Name — Specification
## Objective
What we're building and why. One paragraph.
## Commands
Key Gradle tasks and how to use them:
- `./gradlew assembleDebug` — build debug APK
- `./gradlew test` — run unit tests
- `./gradlew connectedAndroidTest` — run instrumented tests
- `./gradlew lint` — run Android Lint
## Project Structure
Where new code lives in the module hierarchy:
- `:app` — main application module
- `:feature:feature-name` — new feature module
- `:core:data` — data layer (repositories, data sources)
- `:core:domain` — domain layer (use cases, models)
## Code Style
- Kotlin with Jetpack Compose for UI
- MVVM/MVI architecture with ViewModel + StateFlow
- Hilt for dependency injection
- Coroutines + Flow for async operations
- Material 3 design system
## Testing Strategy
- Unit tests: JUnit5 + MockK for ViewModels, use cases, repositories
- UI tests: Compose test rules for screen-level testing
- Integration tests: Room in-memory database, MockWebServer
- Target: critical paths covered, not arbitrary coverage %
## Boundaries
What is explicitly NOT in scope:
- [ ] List exclusions here
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 · 116 lines · 41 tokens per session scan A 766345d5729a
spec-driven-development is a skill published in the GitHub repository GuillemRoca/agent-skills-android (2 stars, last pushed 2mo ago), licensed MIT. It adds 41 tokens to every session and 937 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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