> ## Documentation Index
> Fetch the complete documentation index at: https://hastekit.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Skills

> Attach reusable Agent Skills to your agents

Skills are reusable capability bundles that extend your agent's behavior. Each skill is a zip file containing a **SKILL.md** file with YAML frontmatter. The agent receives skill names, descriptions, and file locations in its system prompt and can read skill content at runtime using the **execute\_bash\_commands** tool.

## Prerequisite: Enable the Bash tool

For the agent to use skills at runtime, the **Sandbox** tool (which provides `execute_bash_commands`) must be enabled:

1. Open your agent in the Agent Builder.
2. Go to the **Tools** tab.
3. Enable **Sandbox** (Bash / execute\_bash\_commands).
4. Save the agent.

Without this, the agent will see skill metadata in its prompt but cannot read the skill files.

## Skill package format

Each skill is distributed as a **.zip** file. The zip must contain a **SKILL.md** file at the root. **SKILL.md** must:

* Start with YAML frontmatter between `---` delimiters.
* Include a **name** field (used in the prompt and UI).
* Include a **description** field (used in the prompt and UI).

Example **SKILL.md**:

```markdown theme={null}
---
name: My Skill Name
description: Short description of when and how to use this skill.
---

Your skill content in Markdown. The agent will read this file when the skill is used.
```

The zip filename (without `.zip`) becomes the **skill folder** name on the server (e.g. `my-skill.zip` → folder `my-skill`). The server parses **SKILL.md** to extract `name` and `description`; invalid or missing frontmatter will cause upload to fail.

## Using the Skills tab in the UI

1. Open the agent: **Agent Framework → Agents → \[your agent]** (e.g. `http://localhost:3000/agent-framework/agents/{agent-id}`).
2. Select the **Skills** tab.

### Saved skills

* Lists skills already attached to the agent (stored under `sandbox-data/{AgentName}_{Version}/skills/`).
* Each row shows **name**, **description**, and **file\_location**.
* Use the delete (trash) icon to **mark for deletion**. Changes apply when you click **Save**; the server removes the skill folder and updates the agent config.

### Upload new skills

* Click **Upload Skill Zip** and choose a `.zip` file that contains a root **SKILL.md** with valid frontmatter.
* The file is uploaded to a **temp** area and parsed; name and description appear under **Pending Skills**.
* You can remove a pending skill with the trash icon (deletes from temp only).
* Click **Save** to **commit** pending skills: each pending skill is moved from temp to the agent’s skills directory and added to the agent config. After save, they appear under **Saved Skills**.

New agents must be created first; the upload button is disabled until the agent exists.

## How skills are used at runtime

The agent config stores a **skills** array of `{ name, description, file_location }`. When building the system prompt, each skill is injected as an available skill; the prompt instructs the agent to use the **execute\_bash\_commands** tool to read the skill file (e.g. `/sandbox/skills/{name}/SKILL.md`). The Sandbox tool mounts the agent’s `skills` directory into the container, so enabling the Sandbox (Bash) tool is required for skills to be usable at runtime.