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 uHappyLogic/cairn --skill derive-tasksgit clone --depth 1 https://github.com/uHappyLogic/cairnWrote 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/uhappylogic/cairn/derive-tasks)<a href="https://agentmods.dev/skills/uhappylogic/cairn/derive-tasks"><img src="https://agentmods.dev/badge/skills/uhappylogic/cairn/derive-tasks.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 5.1 | $0.00029 | $0.01601 |
| Opus 5 | $0.00015 | $0.00800 |
| Sonnet 5 | $0.00006 | $0.00320 |
| Haiku 4.5 | $0.00003 | $0.00160 |
Grade A, and why
derive-tasks 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 yesterday.
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 — 115 lines — stays where its author put it; the contents beside it link to each section on GitHub.
derive-tasks
Reads the current milestone requirements and derives a complete, dependency-ordered list of tasks into TASKS_TODO.md, ready for AI-driven completion via /complete-task.
Your job here is decomposition and coverage. You split the milestone into high-level task briefs, prove that those briefs cover every requirement, order them by dependency, and write them into TASKS_TODO.md yourself — you are the single writer on the derivation path, and nothing here is delegated. Keep every task section at brief altitude: a task states what is to be achieved, and the completer derives the flow and the formal acceptance bar itself from the description plus requirements.md, against the live project.
Usage
/derive-tasks
No arguments. The skill always reads from and writes to the current milestone directory.
Preconditions
- All open questions in the current milestone's
requirements.mdmust be resolved (no<open-questionblock withstatus="open"remains;status="deferred"blocks may carry forward). TASKS_TODO.mdshould be empty or contain only stale tasks from a previous milestone; this skill replaces its contents.
Workflow
0. Find the current milestone
Follow .agents/plugins/cairn/shared/get-current-milestone.md to resolve <MILESTONE_DIR>. Never use a hardcoded task-list path.
1. Read source documents
Read CLAUDE.md at the workspace root for the project's domain context, working conventions, available tools, and how work is verified as done. If it lacks that context, suggest the user run /init first, then proceed.
Read <MILESTONE_DIR>/requirements.md in full, plus any files referenced in its Relevant starting state section, so you understand the exact starting point.
Read the shared task format at .agents/plugins/cairn/shared/task-format.md. That file owns the shape of every task section you write in step 7 — its template and authoring guidelines.
2. Check for unresolved open questions
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.
- yesterday Changed 8d12098a9274
- 3d ago Changed · -16 lines · -27 tokens per session 929a4d549a91
- 4d ago Changed · -2 lines d1888f45c939
- 8d ago First seen · 133 lines · 56 tokens per session scan A e7ec3c961a82
derive-tasks is a skill published in the GitHub repository uHappyLogic/cairn (2 stars, last pushed today), licensed MIT. It adds 29 tokens to every session and 1,601 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.
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Multi-perspective collaborative review of plans or documents. Ten expert viewpoints deliberate in 3 rounds to reach consensus.
plan-task
Structured task planning using Work files. Use for any new feature, bug fix, or project that needs a task breakdown before implementation.
review
Run a full code review on current changes or specified files. Runs ruff lint, review-code agent, and security scan in sequence.