Quick answer
A Claude Code mod prompt works best when it states the goal in one or two sentences, tells Claude to load its mod authoring documentation first, explains any tools it should use, asks it to check whether a feature can be built before saying it is impossible, and ends with a staged test plan and troubleshooting steps.
Key takeaways
- Open with a one or two sentence goal
- Ask Claude to load its mod authoring docs first
- Separate a missing tool from a capability that can be built
- Finish with a staged test plan and troubleshooting steps
This guide answers one question from our article Claude Code Mods: How to Build Your Own Automation Shortcuts: what should you actually write when you ask Claude to build a mod?
📘 Main article: This guide supports our full article, Claude Code Mods: How to Build Your Own Automation Shortcuts. Read it for the complete picture.
Why does the prompt matter so much?
Mods are add-ons that change how Claude Code works: a new tool, a changed behaviour or a shortcut. Claude can write most of the code, but only if it understands exactly what you want and how to check its own work.
In the video behind our main article, the creator notes that Claude sometimes says a feature is not possible until it is pushed to investigate. A good prompt builds that push in from the start.
What sections should a mod prompt include?
| Section | What to write |
|---|---|
| Goal | One or two sentences describing the feature, as if briefing a colleague |
| Prime | “Before writing anything, load your mod or plugin authoring documentation” |
| Context | The tools, apps or files involved and how they connect |
| Feasibility check | “Before deciding this is impossible, inspect the available APIs and help output” |
| Permissions | When it must ask you before acting |
| Test plan | A staged list: one action first, then expand |
| Troubleshooting | What to try if a step fails |
| File layout | Where the mod's files should live |
What does a simple mod prompt look like?
Here is an example for a read-only shortcut:
Goal: build a Claude Code mod called /publish-check that reviews a blog draft for a title, meta description, headings and image alt text, and reports what is missing. Before writing anything, load your mod authoring documentation. The mod must only read files, never edit or publish them. Test it on one draft first, then on three. If a check fails, list the error and suggest a fix. Keep all files in one folder.
Start with a tiny mod. Use the template below to build a one-command shortcut before you try anything that clicks inside apps.
How do you stop Claude saying “that's impossible”?
- Ask it to distinguish a tool missing in this chat from a capability that can be built
- Ask it to check the CLI help and installed APIs before concluding
- If you are copying a feature from another app, ask it to observe that app's logs or tools while you use it
How should you structure the test plan?
- Run the smallest possible version of the feature.
- Confirm the output yourself.
- Expand one step at a time.
- Ask Claude to test its own work after each step.
- Only then use the mod on real tasks.
Expect several rounds. In the video, one advanced mod took about an hour of troubleshooting before it worked.
💡 Tip: Save each version of your prompt. When a build fails, you can compare versions and see which instruction caused the problem.
Want to see two advanced examples? Our Claude Code mods guide walks through a computer-use bridge and a threads mod. More guides on Prodify Digital.
Frequently asked questions
How long should a mod prompt be?
Long enough to cover goal, context, checks and tests. Simple mods may need a paragraph; complex ones several sections.
Should I tell Claude which files to create?
Tell it where files should live. Let it decide the details unless you have a reason not to.
What is the safest first mod?
A read-only shortcut, such as a checklist or report, that cannot change or send anything.
Can I reuse prompts from other people?
Yes, but read them fully and adjust permissions and file paths to your own setup.
What if the mod keeps failing?
Ask Claude to list each error, then fix one at a time with a clear goal for each round.
The bottom line
A good mod prompt is a clear brief plus a test plan. State the goal, prime Claude, require a feasibility check and build in small, verified steps.
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- Claude Code Mods: How to Build Your Own Automation Shortcuts
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