Skill System

Overview

Updated in v0.3.19.

The skill system in Evonic lets you extend agent capabilities with installable packages that bundle tool definitions and Python backends. Starting in v0.3.19, skills have a richer loading system with lazy and eager loading modes, plus descriptive briefs that help you understand what each skill does at a glance.

Skill Loading Behavior

Every skill has a loading behavior that determines when its tools become available:

Mode	Badge	Behavior
Eager (default)	No badge	Tools are loaded and available as soon as the skill is assigned to an agent
Lazy	Lazy badge	Tools are only loaded when the agent explicitly calls use_skill() to activate them

Eager Loading (Default)

Eager-loaded skills have their tools available immediately. When you assign the skill to an agent, all its tools appear in the agent’s tool registry right away.

Best for: Frequently used tools that the agent should always have access to.

Lazy Loading

Lazy-loaded skills are registered but their tools are not automatically loaded into the agent’s context. The agent must call the built-in use_skill() tool to activate them. This keeps the agent’s context lean and reduces token usage.

Lazy skills display a “Lazy” badge on the skill card in the Web UI, making it easy to identify them.

Best for: Specialized or rarely used tools that don’t need to be in context all the time.

How Lazy Loading Works

1. A lazy skill is assigned to the agent (visible in the skill list)
2. The agent decides it needs the skill’s tools
3. The agent calls use_skill({id: "skill_name"}) to load the skill’s tools into context
4. The tools become available for the agent to use
5. When done, the agent can call unload_skill({id: "skill_name"}) to free up context

Skill Briefs

Each skill can have a brief — a short description shown alongside the skill’s name and ID. Briefs help you quickly understand what a skill does without opening its details.

In v0.3.19, briefs are displayed on:

• Skill cards in the Web UI (/skills page)
• Skill assignment interfaces when configuring an agent
• Skill ID display — the skill ID is now shown alongside its name in the card list

Visual Indicators

Skill ID

Starting in v0.3.19, each skill’s ID (the unique identifier like kanban, hello_world) is displayed on its card in the skill list. This makes it easy to identify skills when using CLI commands that reference skill IDs.

Lazy/Eager Badges

Skills with lazy loading display a “Lazy” badge on their card. Eager-loaded skills (the default) show no badge. This visual distinction helps you understand the loading behavior at a glance.

Managing Load Behavior

The loading behavior is defined in the skill’s manifest (skill.json). When creating a skill, you can set it to lazy or eager:

{
  "id": "my-skill",
  "name": "My Skill",
  "version": "1.0.0",
  "lazy": true,
  "description": "Brief description shown in skill cards"
}

• "lazy": true — Skill uses lazy loading (shows “Lazy” badge)
• "lazy": false or omitted — Skill uses eager loading (default, no badge)

Example: Eager vs Lazy in Action

Skill	Load Mode	Badge	When Tools Are Available
Kanban	Eager	None	Immediately on assignment
File Converter	Lazy	Lazy	After agent calls use_skill()

Benefits

• Reduced token usage — Lazy skills don’t bloat the agent’s context until needed
• Cleaner tool lists — Agents only see tools from eager skills by default
• Better discoverability — Briefs and skill IDs make it easier to find the right skill
• Clear visual feedback — Badges tell you the loading behavior at a glance