A skill for turning a software request into a detailed implementation plan, including architecture, phases and dependencies. It also checks unfinished plans in the project’s plans directory before creating or updating one.

Use it to design systems, plan features, document technical roadmaps, define implementation phases and record relationships between related plans.

It makes large changes easier to organise and exposes when one planned task must wait for another. This reduces the risk of starting work with missing decisions or conflicting plans.

ck:plan — Skill for Claude Code by bestagentkits

Install

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.

Any agent

npx skills add bestagentkits/ck-skills --skill ck-plan

Clone the repo

git clone --depth 1 https://github.com/bestagentkits/ck-skills

Made for: Claude Code.

Or install ck-skills, the plugin that ships this one along with the rest of its 14 skills.

Wrote 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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/bestagentkits/ck-skills/ck-plan/github.svg)](https://agentmods.dev/skills/bestagentkits/ck-skills/ck-plan)

Your own site

<a href="https://agentmods.dev/skills/bestagentkits/ck-skills/ck-plan"><img src="https://agentmods.dev/badge/skills/bestagentkits/ck-skills/ck-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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/bestagentkits/ck-skills/ck-plan"><img src="https://agentmods.dev/badge/skills/bestagentkits/ck-skills/ck-plan.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 35 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 2,111 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

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	$0.00035	$0.02111
Opus 5	$0.00017	$0.01056
Sonnet 5	$0.00007	$0.00422
Haiku 4.5	$0.00003	$0.00211

Measured 10d ago against content hash 8c99707237ec, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

ck: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 10d 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.

plugins/ck-skills/skills/ck-plan/SKILL.md · 199 lines

How it starts

The opening of the file, as written. The whole thing — 199 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Planning

Create detailed technical implementation plans through research, codebase analysis, solution design, and comprehensive documentation.

IMPORTANT: Before you start, scan unfinished plans in the current project at ./plans/ directory, read the plan.md, if there are relevant plans with your upcoming plan, update them as well. If you're unsure or need more clarifications, use AskUserQuestion tool to ask the user.

Cross-Plan Dependency Detection

During the pre-creation scan, detect and mark blocking relationships between plans:

Scan — Read plan.md frontmatter of each unfinished plan (status != completed/cancelled)
Compare scope — Check overlapping files, shared dependencies, same feature area
Classify relationship:
- New plan needs output of existing plan → new plan blockedBy: [existing-plan-dir]
- New plan changes something existing plan depends on → existing plan blockedBy: [new-plan-dir], new plan blocks: [existing-plan-dir]
- Mutual dependency → both plans reference each other in blockedBy/blocks
Bidirectional update — When relationship detected, update BOTH plan.md files' frontmatter
Ambiguous? → Use AskUserQuestion with header "Plan Dependency", present detected overlap, ask user to confirm relationship type (blocks/blockedBy/none)

Frontmatter fields (relative plan dir paths):

blockedBy: [260301-1200-auth-system]     # This plan waits on these plans
blocks: [260228-0900-user-dashboard]     # This plan blocks these plans

Status interaction: A plan with blockedBy entries where ANY blocker is not completed → plan status should note blocked in its overview. When all blockers complete, the blocked plan becomes unblocked automatically on next scan.

Default (No Arguments)

If invoked with a task description, proceed with planning workflow. If invoked WITHOUT arguments or with unclear intent, use AskUserQuestion to present available operations:

Operation	Description
`(default)`	Create implementation plan for a task
`archive`	Write journal entry & archive plans
`red-team`	Adversarial plan review
`validate`	Critical questions interview

Read the full file on GitHub · 199 lines

Files

What ships with it

13 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.

Changes

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.

10d ago First seen · 199 lines · 35 tokens per session scan A 8c99707237ec

Subscribe to this mod's changes

ck:plan is a skill published in the GitHub repository bestagentkits/ck-skills (6 stars, last pushed 3mo ago), licensed MIT. It adds 35 tokens to every session and 2,111 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.

Claude Code Planning agent-tools ai-agents claude-skills goclaw plugin-marketplace

adr

Use when the user knows what they want built and says "/adr", "write an ADR for X", "decide and build X", or "ADR-driven". Turns an intent into a grounded, cited, build-ready ADR at docs/adr/YYYY-MM-DD- .md — load-bearing decisions surfaced to the human — then hands off to nightshift:plan's landing step (the plan is…

jasonm4130/claude-skills · 138 tokens

plan

Use when the user has an idea, feature, or fix that is more than a one-sitting edit and says "plan this", "write a plan for X", "/nightshift:plan", or "what would it take to build X". Sizes the work (trivial → no artifact; medium → a lean plan; large → a short spec first), asks one question at a time until the design…

jasonm4130/claude-skills · 183 tokens

watch

Use when a Nightwatch spec queue is about to run, or is already running, and someone needs to fire it, watch it, and steer it — "launch nightwatch", "watch the run", "/nightwatch:watch", "pause it", "skip that spec". Runs preflight, launches run.sh, arms the journal and workflow-journal monitors, knows what is safe to…

jasonm4130/claude-skills · 147 tokens

domain-modeling

Use when pinning down domain terminology, building a ubiquitous language or project glossary, disambiguating overloaded or vague terms, or maintaining a CONTEXT.md — or when another skill needs to sharpen the domain model. Do NOT use for recording architectural decisions (use adr) or for writing implementation specs.

jasonm4130/claude-skills · 63 tokens

morning

Use when the user says "/nightshift:morning", "what happened overnight", "how did the night go", "why did the loop stop", or opens a session in a repo with a loop/ directory after a scheduled run. Reads the journal since the last start line and every open land / land:blocked pull request, says per stop what happened…