Guide · Agent skill
How to use the Understand Domain agent skill (understand-domain)
Updated · written with AI from the project's own documentation and checked against our catalogue data
The understand-domain skill is an agent skill that reads a software project and extracts the business-level picture behind the code: domains, business flows and process steps. It is meant for engineers who want a map of what the product does rather than a file-by-file tour. After this guide you will know what the skill does, how to install it, how to ask for it in plain language, and what it needs to run.
Understand DomainEgonex-AI/Understand-Anything · MIT Download the skill Quick start
- 1Download the ZIP. Download the understand-domain ZIP from this page.
- 2Unzip into a skills folder. Unzip it into ~/.claude/skills/ for personal use, or into your project's .claude/skills/ folder.
- 3Or upload in the Claude apps. In the Claude apps, go to Settings → Capabilities → Skills and upload the ZIP.
- 4Confirm Git and Python 3. Make sure Git and Python 3 are available, and that the understand-anything plugin is installed.
- 5Make a request. Ask the agent to map the business domains and processes of your project, or run /understand-domain.
- 6Refresh if needed. If the skill warns about changes, run /understand to refresh the knowledge graph, then run the skill again.
- 7View the dashboard. Open the Understand-Anything dashboard to see the interactive horizontal flow graph.
What is an agent skill, and what does understand-domain do?
An agent skill is a folder containing a SKILL.md instruction file and any supporting files, which an AI coding agent loads when a request matches the skill. The understand-domain skill (from the Understand-Anything plugin, MIT licensed) tells the agent how to extract business domain knowledge from a codebase and generate an interactive domain flow graph.
When invoked, the agent looks for an existing knowledge graph from the companion /understand command. If one exists, it derives the domain view from that graph without rescanning files. If not, it runs a lightweight scan of the file tree, entry points and sampled source files. The result is an interactive horizontal flow graph shown in the Understand-Anything dashboard.
Install the understand-domain skill
You can install the skill by downloading the ZIP from this page and unzipping it into one of two places: ~/.claude/skills/ for personal use across projects, or .claude/skills/ inside a specific project.
If you use the Claude apps, you can instead upload the ZIP under Settings → Capabilities → Skills.
- Personal install: unzip into ~/.claude/skills/
- Project install: unzip into your project's .claude/skills/ folder
- Claude apps: Settings → Capabilities → Skills, then upload the ZIP
Check the requirements before you run it
The skill needs three things. Git is required because the skill runs git rev-parse and git diff to check whether the graph is fresh and to detect worktrees. Python 3 is required to run the bundled extract-domain-context.py script. You also need the understand-anything plugin installed, since its dashboard is where you view the graph.
The skill runs scripts but does not use the network, according to this listing.
- Git
- Python 3
- The understand-anything plugin, with its dashboard
How to trigger the skill with natural requests
The skill is invoked by its name or by requests that match its description. The SKILL.md lists an optional argument, --full, which forces a fresh scan even when a knowledge graph already exists. The slash name /understand-domain is the form shown in the skill's instructions.
Plain requests are usually enough. Examples of phrasing that matches the skill's purpose include asking the agent to map the business domains of the project, or to show how the product's processes fit together.
- Map the business domains and processes in this codebase.
- Run /understand-domain to show the domain flows.
- Run /understand-domain --full to rescan instead of using the existing graph.
- Give me a business-level view of this project, not a file-level one.
/understand-domain --fullUnderstand what the output means and when to refresh it
The output is inferred from code. If a knowledge graph exists, the skill checks whether project files changed since the graph was built, comparing the graph's recorded commit with the current HEAD and with uncommitted and untracked changes. If changes are found, it warns that domain extraction may omit them and suggests running /understand to refresh the knowledge graph.
If you are working in a git worktree, the skill redirects its output to the main repository root, because worktree data directories are described as ephemeral. You can keep the worktree as the root by setting UNDERSTAND_NO_WORKTREE_REDIRECT=1.
Safety notes on scripts and data
The skill runs a bundled Python script and several git commands in your project. The listing says it uses no network. Generated artifacts are written to a data directory named .ua/ (or the legacy .understand-anything/ if that already exists in the project). The skill's instructions ignore that directory in change checks, since it holds generated graph files rather than source drift.
Read SKILL.md and extract-domain-context.py before running the skill on sensitive code, since it is a script you are choosing to execute.
What people use it for
- Onboarding onto an unfamiliar codebase with a business-level map of its processes.
- Documenting how a product's domains and process steps fit together for a team.
- Adding a domain view on top of an existing /understand knowledge graph.
- Reviewing which business flows a codebase contains before planning changes.
Frequently asked questions
Is the understand-domain skill free?
The skill is published under the MIT licence, as stated on this page. Check the licence file in the repository for the full terms.
What do I need to install understand-domain?
Install the skill by unzipping the download into ~/.claude/skills/ or a project's .claude/skills/, or upload the ZIP under Settings → Capabilities → Skills. It also needs Git, Python 3, and the understand-anything plugin with its dashboard.
Does understand-domain need an internet connection?
This listing says the skill does not use the network. It does run scripts and git commands locally in your project.
What is the difference between understand and understand-domain?
/understand builds a knowledge graph of the codebase. understand-domain reads that graph, when it exists, and derives business domains, flows and process steps from it. Without a graph, it runs its own lightweight scan.
Why does the skill say my domain graph may be out of date?
The skill compares the graph's recorded commit with your current project files, including uncommitted and untracked changes. If project files changed, the output may miss them, and the skill suggests running /understand to refresh the graph.
What should I do if the skill cannot find the plugin root?
The skill's instructions list the locations it checks for the understand-anything plugin, and it stops with an error if none contain the required files. Confirm the plugin is installed correctly, then try again.
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Our verdict
Use understand-domain if you are onboarding onto a non-trivial codebase or documenting how a product's processes fit together, and you already have or are happy to build the understand-anything graph. Skip it on very small projects, where reading the code directly is faster, and do not treat its output as verified business documentation, since it is inferred from code and can miss recent changes.
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