What you will build

A “morning blinds” skill. The robot opens your bedroom blinds at a user-configured time each weekday. Tiny on purpose: just enough to touch every layer of the platform without drowning you in logic.

Step 1 — Install the CLI

npm install -g @geraskills/cli. The CLI ships with a local simulator so you can test without owning a compatible robot. Run geraskills doctor to check your environment before continuing.

Step 2 — Scaffold

geraskills init morning-blinds creates the package layout: manifest.yaml, src/skill.ts, test/, assets/. The manifest is the declarative half of your skill — capabilities, permissions, compatible robots, pricing hint.

Step 3 — Write the manifest

Declare what you need up-front. The runtime enforces every permission at execution time, so understate rather than overstate. Our blinds skill needs capability: window-blinds, room: bedroom, and a scheduled-trigger. That is it.

Step 4 — Implement the state machine

Every skill is a state machine. The API spec deep-dive has the contract. For the blinds skill: IDLE → TRIGGERED → NAVIGATING → OPERATING → IDLE. Each transition has a handler; each handler has a timeout; each handler returns success, retry, or abort.

Step 5 — Test against the simulator

geraskills sim run drops you into a simulated bedroom. Your skill executes against fake sensors and actuators; you watch the state machine progress. This is where you catch the obvious bugs (navigating to wrong room, sending the wrong actuator command) before a real robot touches anything.

Step 6 — Sign and submit

geraskills sign produces a signature using your developer key. geraskills submit uploads the signed bundle to the catalogue. Safety review is automated for low-risk skills (mine is) and human-reviewed for physical-risk skills (anything involving knives, heat, or navigation near children).

Step 7 — Wait for review, then list

Automated review is usually minutes. If listed, set pricing in the creator dashboard. For a skill this trivial, £0.99 one-off or free-with-donations is realistic. Don’t expect to retire on your blinds skill.

What you just learned

The manifest is the contract. Understate.
The state machine is the logic. Keep transitions small.
The simulator is the dev loop. Use it.
Signing + review is the trust layer. Don’t skip.

Cross-links

Ready for more? See the publishing checklist and the API deep-dive. Payment processing across countries is handled via GeraCash; skill-to-skill action chaining routes through GeraNexus.