Agent Engineering
The Essence of Skill
Equipping an Agent with an "Operations Manual": an Agent without Skills is like a new hire feeling their way; an Agent with Skills is like a veteran following standard procedures.
Comparative Simulation: Click the "Simulate" button on each side
Inefficient
Agent without Skill
Rounds 0
Tokens 0
Errors 0
Every step relies on general capabilities
Efficient
Agent with Skill
Rounds 0
Tokens 0
Errors 0
Executes step by step per Skill manual
Skill Definition Card and Product Decisions
Skill Definition Card
One SKILL.md file = one skill
Skill Name
release
Triggers
deploy
build
release
publish
Steps
1Run tests
→
2Build
→
3Update version
→
4Tag
→
5Push remote
Allowed Tools
run_command
edit_file
git
Storage path: ~/.alice/skills/release/SKILL.md or {project}/.alice/skills/
📌 Skills are encapsulated experience: Write senior engineers' workflows into a manual the Agent can understand. The Agent no longer starts from scratch every time — it stands on the shoulders of those who came before.
📌 Efficiency gap can exceed 3×: Without Skills, an Agent fumbles with general capabilities; with Skills, it executes best practices. Token consumption differs by 3.75×, errors go from 3 to 0.
📌 Questions PMs need to answer: Which high-frequency operations get pre-installed Skills? Can users create their own Skills? How to handle Skill conflicts? Who maintains and updates Skills?
Takeaway
Takeaway Skills turn "fumbling" into "execution." For the same release task: without a Skill, the Agent makes 12 trial-and-error rounds using 15K Tokens and 3 errors; with a Skill, done in 5 rounds using only 4K Tokens and zero errors. Skills are the experience-transmission mechanism for Agents.