Skills.md from Scratch: Build a Skill-Driven Coding Agent
We start from the coding agent from the prerequisite workshop and turn it into a general-purpose coding agent with two reusable behavior layers: skills and slash commands. Skills are loaded by the agent when the user's request matches a skill description. Commands are invoked by the user with a leading slash and rendered into prompts before the agent acts.
Links
External resources for this workshop:
- Starting notebook
- GitHub fetch skill
- Prototype implementation
- Prerequisite coding-agent workshop
- ToyAIKit
- OpenCode
- OpenCode skills documentation
- AgentSkills spec
The agent you will build
The final workshop system looks like this:
The project stays small enough to understand in a notebook, but it mirrors
the pieces used by real coding agents. The coding tools let the model read,
write, search, and run commands. The skill loader turns SKILL.md files with
YAML frontmatter into tool-loadable instructions. The command loader turns
markdown files like review.md or test.md into reusable prompt templates.
Appendix
A file list for the workshop materials is in Appendix: workshop files.
Materials
Tutorial pages
- Overview and setup
- Part 1: Demoing skills and commands
- Part 2: Recapping the coding agent
- Part 3: Building the base runner
- Part 4: Defining the skill format
- Part 5: Loading `SKILL.md`
- Part 6: The skill tool and prompt injection
- Part 7: Implementing commands
- Part 8: The fuller prototype
- Q&A: skills and commands
- Deferred items
- Appendix: workshop files
Watch the recording
Full workshop video with timestamps and downloadable materials.
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