SKILLS · CUSTOM

Create a custom skill

Turn a procedure you repeat into a skill a persona can use again. Start with one clear task and a short SKILL.md file.

Choose a useful boundary

A good first skill produces one recognizable result. “Review a website brief for missing requirements” is easier to write and check than “Handle all website work.” Include when to use it, the steps to follow, and what the result should contain.

Keep account passwords and API keys in their integration settings. Skill files should describe the work and refer to the connected services they need.

1. Open the custom skill editor

1. Open Integrations and find Custom Skills.
2. Choose Add custom skill.
3. Enter a Skill name, such as review-website-brief.
4. Choose Start blank.
5. Edit the generated SKILL.md.

Names use letters, numbers, and single hyphens. PersonaStack converts the name to lowercase. The name inside an imported SKILL.md must match the skill name.

2. Write a complete first version

Keep the required name and description at the top of the file. Then write instructions the persona can follow without guessing:

---
name: review-website-brief
description: Review a small website brief for missing requirements before planning the work.
---

# Review a website brief

Use this skill when asked to review a website brief.

1. Identify the audience and the main action visitors should take.
2. Check for required pages, supplied content, and a target launch date.
3. List missing details as questions. Do not invent answers.
4. Return a short summary followed by no more than five questions.

Do not publish a website or change files as part of this review.

Choose Create skill when the file is ready.

Import an existing skill

Instead of starting blank, choose Upload ZIP or Choose folder. The editor accepts a text-only skill folder with a valid SKILL.md. The form currently allows up to 128 files and 512 KiB.

Inspect the imported file tree before saving. Remove unrelated material and make sure any file referenced by the instructions is included. Save or discard your current edits before replacing the full file tree.

3. Enable it for a persona

Open the persona’s settings. Under Integrations → Knowledge, select the custom skill. Wait for the saved state, then ask the persona to review a short sample brief.

Compare its response with the steps you wrote. If the skill is unclear, improve the instructions before giving it a larger task.

You can also select the skill in the persona’s Skills picker. This works for hosted and external personas. A selected custom skill stays private to its workspace. Clients authorized for that persona can read its instructions and supporting files through MCP. Review those files before assigning the skill to a persona used by an external client.

The client must support the MCP Skills extension to load the skill. It controls approval and command execution. PersonaStack does not install local programs or grant host permissions through MCP. See Use selected skills in your MCP client.

Edit an existing skill

Return to Custom Skills, choose View and edit files, and make the changes. Save new version records the next version. Check the persona’s skill status before trying the revised workflow.

Deleting a custom skill removes all its saved versions and removes access for personas using it. Remove a persona’s assignment instead when you only want that persona to stop using the skill.

Connected MCP clients must refresh their skill list after a new version or assignment change. Subsequent reads of a removed selection or superseded version fail. PersonaStack cannot recall copies a client already downloaded.

Open Custom Skills ↗

Need a hand? Contact the PersonaStack team.