Custom Skills

Skills are domain expertise documents that give agents specialized knowledge. A skill is a markdown file with structured sections — tone guidelines, rules, examples, and reference material — that gets injected into the agent's prompt when processing tasks.

What Are Skills?

Think of skills as training documents for your agents. Instead of cramming everything into the system prompt, you create modular skills that can be:

• Attached to one or many agents
• Activated always, per-board, or per-tag
• Versioned and updated independently
• Exported and shared across organizations

Examples of skills:

• "Brand Voice Guide" — tone, vocabulary, do's and don'ts for customer-facing content
• "CS Email Templates" — standard response templates for common customer issues
• "SEO Content Brief" — keyword research process and content structure guidelines
• "Code Review Checklist" — what to check in pull request reviews

Creating a Skill

From the Editor

1. Navigate to Skills in the sidebar
2. Click + New Skill
3. Fill in the metadata:
   • Name — descriptive name
   • Category — grouping (e.g., "Marketing", "Customer Service")
   • Tags — labels for filtering
   • Description — what this skill teaches the agent
4. Write the skill content in the markdown editor
5. Configure activation (see below)
6. Click Save

From a File (Import)

Upload an existing markdown file as a skill:

1. Go to Skills and click Import
2. Select a .md file from your computer
3. HELIX parses the frontmatter and content
4. Review and save

Skill Format

Skills use YAML frontmatter followed by markdown content:

---
name: Brand Voice Guide
version: "1.0.0"
description: Tone and vocabulary rules for customer-facing content
category: Marketing
tags:
  - brand
  - writing
  - tone
---

# Brand Voice Guide

## Tone

Our brand voice is professional yet approachable. We speak with
confidence but never condescension.

## Rules

- Use active voice: "We built this feature" not "This feature was built"
- Address the reader as "you": "You can configure..." not "Users can configure..."
- Keep sentences under 25 words
- Avoid jargon unless writing for a technical audience

## Examples

### Good
"Get started in under 5 minutes with our one-command installer."

### Bad
"The installation process can be initiated by executing the provided shell script."

## Do

- Use contractions (we're, you'll, it's)
- Lead with benefits, not features
- Include concrete numbers when possible

## Don't

- Use passive voice
- Say "please" excessively
- Use exclamation marks in body copy
- Reference competitors by name

Frontmatter Fields

Field	Type	Required	Description
name	string	Yes	Skill name
version	string	No	Semantic version (default: "1.0.0")
description	string	No	What this skill does
category	string	No	Category for grouping
tags	string[]	No	Tags for filtering

Recommended Sections

Section	Purpose
Tone	Communication style and voice guidelines
Rules	Hard rules the agent must follow
Examples	Good and bad output examples
Do / Don't	Quick reference lists
Templates	Reusable output templates
Reference	Background information and data

Activation Modes

Control when a skill is injected into an agent's prompt:

Mode	Behavior
Always	Skill is active for every task the agent processes
Board Specific	Skill activates only for tasks on specific boards
Tag Specific	Skill activates only for tasks with specific tags

Board-Specific Example

A "Meta Ads Copy" skill activates only for tasks on the "Meta Ads" board. The agent doesn't see this skill when working on SEO tasks.

Tag-Specific Example

A "Urgent Response" skill activates only for tasks tagged with urgent. The agent applies different guidelines for urgent vs. normal tasks.

Attachments

Attach files to a skill to provide reference material:

• Supported file types: PDF, images, text files, spreadsheets
• Use cases: Brand style guides, product catalogs, example documents
• Size limit: Per-file limit configured in your plan

Managing Attachments

1. Open a skill
2. Go to the Attachments tab
3. Click Upload to add files
4. Add a description to each attachment
5. Delete attachments you no longer need

Attachments are stored on the server and referenced by the agent during task execution.

Assigning Skills to Agents

From the Skill Page

1. Open a skill
2. Click Assign to Agents
3. Select which agents should use this skill

From the Agent Page

1. Open an agent's settings
2. Go to the Skills section
3. Add or remove skill assignments

An agent can have multiple skills. Skills are layered on top of the agent's system prompt (SOUL.md) and memory.

Exporting Skills

Export a skill as a markdown file to share or back up:

1. Open the skill
2. Click Export
3. A .md file downloads with the frontmatter and content

How Skills Are Injected

When an agent processes a task, HELIX builds the prompt in this order:

1. System prompt (SOUL.md) — agent identity
2. MEMORY.md — learned rules
3. Active skills — filtered by activation mode:
   • Always-active skills are always included
   • Board-specific skills are included only if the task is on the matching board
   • Tag-specific skills are included only if the task has the matching tag
4. Task details — title, description, comments

The agent sees all active skills as part of its context, giving it the domain expertise needed for the task.