Skills

Skills are the simplest extension point. They are markdown files with TOML frontmatter that provide instructions to the agent. No code execution — skills teach the agent how to behave and what steps to follow.

File format

+++
name = "daily-briefing"
description = "Compile and deliver a daily briefing"
version = "1.0.0"
triggers = ["command:briefing", "schedule:daily"]

[requires]
tools = ["web-search", "calendar"]
+++

## Instructions

1. Check the user's calendar for today
2. Summarize top news from their preferred sources
3. List any pending tasks or reminders
4. Format as a concise morning briefing

Triggers

Skills are activated by triggers:

• command:name — activated when the user sends /name in Telegram
• schedule:... — marks the skill as scheduler-driven
• Ambient — skills without triggers are always included in the system prompt

[[schedules]]
name = "morning-briefing"
type = "agent"
schedule = "0 8 * * *"
skill = "daily-briefing"

Directory structure

~/.denkeeper/
├── skills/                  # Global skills (shared across agents)
│   ├── daily-briefing.md
│   └── expense-tracker.md
└── agents/
    └── default/
        └── skills/          # Agent-specific skills (override global)
            └── custom.md

Agent-specific skills are merged with global skills. If both define a skill with the same name, the agent-specific version wins.

Creating skills at runtime

In supervised or autonomous tiers, the agent can create new skills via the Config MCP server. In supervised mode, this requires human approval via the approval workflow.

Undoing a skill change

Every runtime skill change — from the agent’s own Config MCP tools, the REST API, or the external MCP server — is recorded in an undo journal before it is applied. Each entry holds the file’s raw prior bytes, so a revert restores exactly what was there rather than a re-rendered approximation: a frontmatter field this build does not recognise still survives the round trip.

The skill_revert tool on the MCP server applies the inverse — deleting a created skill, restoring an updated or deleted one, renaming a renamed one back. Each journal entry can be spent only once, and the claim is persisted, so a revert cannot be applied twice even across a restart.

Reverting restores the skill file. It does not undo what the skill did while it was live: messages already sent, tool calls already made and KV keys already written stay as they are.