yylo: Skill for Claude Code

.agents/skills/understand-project/SKILL.md

understand-project is a skill for Claude Code from yylo-dev/yylo. It costs 23 tokens per session (303 once invoked), scanned A, original, MIT.

A project-inspection skill that reviews the product’s structure, installed libraries, and ways of checking changes before work begins.

In plain words
What is it for?
Use it before implementing a requested change, especially in an unfamiliar codebase or product.
Why use it?
It reduces the risk of planning changes without understanding how the project is built or how its results are tested.

Skill for Claude Code

Written for Claude Code: argument-hint in frontmatter. Also seen: mentions CLAUDE.md; positional $N argument; installed under .agents/ (shared by several agents).

This is yylo-dev/yylo's own configuration. It tells Claude Code how to work on yylo itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything yylo configures →

Reuse

Borrowing it

Nothing to install: this file belongs to yylo-dev/yylo. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/yylo-dev/yylo/main/.agents/skills/understand-project/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/yylo-dev/yylo

Made for: Claude Code.

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.

agentmods badge for understand-project

README.md
[![agentmods](https://agentmods.dev/badge/skills/yylo-dev/yylo/understand-project.svg)](https://agentmods.dev/skills/yylo-dev/yylo/understand-project)
Your own site
<a href="https://agentmods.dev/skills/yylo-dev/yylo/understand-project"><img src="https://agentmods.dev/badge/skills/yylo-dev/yylo/understand-project.svg" alt="Measured on agentmods" height="20"></a>
Per session 23 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 303 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00023 $0.00303
Opus 5 $0.00012 $0.00151
Sonnet 5 $0.00005 $0.00061
Haiku 4.5 $0.00002 $0.00030

Measured 8d ago against content hash ced6c100ddd1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

understand-project 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 8d 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.

.agents/skills/understand-project/SKILL.md · 32 lines

What it actually says

Understand the project

  1. Read AGENTS.md/CLAUDE.md, repository status, relevant source, tests, and existing product documentation in the integration or assigned feature worktree.
  2. Read related Kanban tasks and durable specs through the canonical metadata controller. Do not assume .juno_task/plan.md exists and do not materialize controller-private metadata in a product worktree.
  3. Trace only the dependencies and runtime paths needed for the requested goal. Use bounded parallel investigation when independent questions justify it.
  4. Report current behavior, sources of truth, affected components, risks, unknowns, and the smallest useful validation loop.
  5. If the user requested planning, hand the findings to plan-kanban-tasks. If implementation was requested, work only in the task worktree returned by yy task start TASK_ID.
  6. Write a durable spec only when requested or materially useful, and route it to a controller-admitted location. Do not update root instructions with transient status.

Invocation contract

The structured views below intentionally alias parts of the complete request; they are not additional user arguments.

Main task

$1

Constraints and context

$2

Complete raw request

$ARGUMENTS

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.

  1. 8d ago First seen · 32 lines · 23 tokens per session scan A ced6c100ddd1

Subscribe to this mod's changes

understand-project is a skill published in the GitHub repository yylo-dev/yylo (57 stars, last pushed 4d ago), licensed MIT. It adds 23 tokens to every session and 303 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 2026-08-30.