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 martinffx/atelier --skill spec-plangit clone --depth 1 https://github.com/martinffx/atelierWrote 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/martinffx/atelier/spec-plan)<a href="https://agentmods.dev/skills/martinffx/atelier/spec-plan"><img src="https://agentmods.dev/badge/skills/martinffx/atelier/spec-plan/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/martinffx/atelier/spec-plan"><img src="https://agentmods.dev/badge/skills/martinffx/atelier/spec-plan.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 | $0.00090 | $0.02964 |
| Opus 5.5 | $0.00036 | $0.01186 |
| Sonnet 5.5 | $0.00018 | $0.00593 |
| Haiku 4.5 | $0.00009 | $0.00296 |
Grade A, and why
spec-plan 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 3d 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 — 343 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Spec Plan
Write a proportional plan so clear that any engineer can follow it. The selected planning mode determines whether the plan stays in the conversation or becomes a persisted structured artifact. This skill does not write code or start implementation.
atelier-orchestrator owns automatic classification and the human may override it. When this
skill is directly invoked without a selected mode, use Spec-backed Plan. If Inline planning
reveals substantial design or coordination needs, ask the human whether to switch to a
Spec-backed Plan before presenting the plan.
Terminal boundary
This skill produces exactly one plan output and then stops:
- Inline mode presents the plan in conversation and changes no repository files.
- Spec-backed mode creates or updates only
plan.jsonfrom an approveddesign.md.
Planning drafts and annotation cycles stay in conversation. Do not modify design.md, persist
a Markdown plan draft, create tracker entries, invoke another workflow skill, or edit
implementation files. These rules still apply when the human asks to plan and implement in one
request. Implementation requires a later, explicit request after this skill has finished.
Planning Rules
- Organize tasks around required behavior, not one task per layer.
- Record a short list of behavior the change must preserve.
- For each task, identify existing code to reuse, modify, or delete.
- Map every new abstraction to a present requirement and its current consumers.
- Introduce shared infrastructure only when at least two current consumers demonstrate the same need.
- Group tests by changed contract and active boundary. Do not repeat the CRUD matrix across layers.
- Plan tests at each module's interface, not past it (see oracle-codebase-design).
Proportionality Gate
Before presenting any plan, compare its size and concepts with the requested behavior. If a bounded migration or refactor introduces shared infrastructure, unrelated behavior, or a plan substantially larger than the behavior being changed, stop and simplify it.
What ships with it
1 file 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.
- 3d ago Changed · -1 lines 5d446ea0ff59
- 11d ago Changed · +20 lines df6786407436
- 1mo ago First seen · 324 lines · 90 tokens per session scan A 2711c9081834
spec-plan is a skill published in the GitHub repository martinffx/atelier (48 stars, last pushed 3d ago), licensed MIT. It adds 90 tokens to every session and 2,964 once invoked, about $0.0004 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 2026-08-30.
Other skills, from other repositories
harbor
Harbor intake for external work — the captain only handles unresolved decisions. Sweeps incoming issues and PRs, verifies every claim before disposition, reuses every decision already made, and hands the maintainer a docket whose pending items each carry one question with options, recommendation, impact and evidence.…
pr
Draft a PR body from OMC's paper trail — the smallest visual that proves the change, evidence consumed from the verify protocol (never re-collected), reversibility from the ADR test on the diff, glossary language throughout.
omc-review
Evaluate finished work for defects, risk, and simplification before it ships.
tech-debt-collector
Evidence-gated tech debt and bloat detection. Scouts signals, ranks by materiality, validates by refutation, reports up to 5 findings with actions.
pr-review
Intent-aware map-reduce PR review with CI/CD support, confidence gating, and intelligent comment deduplication.
pr-walkthrough
Generate an evidence-grounded markdown walkthrough for a pull request.