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/douglance/sdlc-plugin/incremental-implementationnpx skills add douglance/sdlc-plugin --skill incremental-implementationgit clone --depth 1 https://github.com/douglance/sdlc-pluginWhat 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 | $0.00020 | $0.01527 |
| Opus 5 | $0.00010 | $0.00763 |
| Sonnet 5 | $0.00004 | $0.00305 |
| Haiku 4.5 | $0.00002 | $0.00153 |
Grade A, and why
incremental-implementation 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 — 218 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Incremental Implementation
When to Use
- Implementing any multi-file change
- Building a new feature from a task breakdown
- Refactoring existing code
- Any time you're tempted to write more than ~100 lines before testing
When NOT to use: Single-file, single-function changes where the scope is already minimal.
The Increment Cycle
┌──────────────────────────────────────┐
│ │
│ Implement ──→ Test ──→ Verify ──┐ │
│ ▲ │ │
│ └───── Commit ◄─────────────┘ │
│ │ │
│ ▼ │
│ Next slice │
│ │
└──────────────────────────────────────┘
For each slice:
- Implement the smallest complete piece of functionality
- Test — run the test suite (or write a test if none exists)
- Verify — confirm the slice does what the increment intended (tests pass, build succeeds, drive it and observe the result)
- Record -- when the task includes commit authority, save the verified slice as an atomic
commit (see
git-workflow-and-versioning) - Move to the next slice — carry forward, don't restart
Slicing Strategies
Vertical Slices (Preferred)
Build one complete path through the stack:
Slice 1: Create a task (DB + API + basic UI)
→ Tests pass, user can create a task via the UI
Slice 2: List tasks (query + API + UI)
→ Tests pass, user can see their tasks
Slice 3: Edit a task (update + API + UI)
→ Tests pass, user can modify tasks
Slice 4: Delete a task (delete + API + UI + confirmation)
→ Tests pass, full CRUD complete
Each slice delivers working end-to-end functionality.
Contract-First Slicing
When backend and frontend need to develop in parallel:
Slice 0: Define the API contract (types, interfaces, OpenAPI spec)
Slice 1a: Implement backend against the contract + API tests
Slice 1b: Implement frontend against mock data matching the contract
Slice 2: Integrate and test end-to-end
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 · 218 lines · 20 tokens per session scan A 4adddf2b4b2b
incremental-implementation is a skill published in the GitHub repository douglance/sdlc-plugin (4 stars, last pushed 1mo ago), licensed MIT. It adds 20 tokens to every session and 1,527 once invoked, about $0.0001 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
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
next-cache-components-adoption
Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…
babysit-pr
Babysit a GitHub pull request after creation by continuously polling review comments, CI checks/workflow runs, and mergeability state until the PR is merged/closed or user help is required. Diagnose failures, retry likely flaky failures up to 3 times, auto-fix/push branch-related issues when appropriate, and keep…
imagegen
Generate or edit raster images when the task benefits from AI-created bitmap visuals such as photos, illustrations, textures, sprites, mockups, or transparent-background cutouts. Use when Codex should create a brand-new image, transform an existing image, or derive visual variants from references, and the output…
cpu-profile-analysis
Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…
next-cache-components-optimizer
Drive a Next.js route to instant navigation by setting up an agentic loop, under Cache Components / PPR, on initial load (hard navigation) and client-side navigation (soft navigation). Encode the goal as a failing @next/playwright instant() e2e and work it to green, one verified route at a time; the shipped test then…