Docker
When to use
Use this skill for docker when you need to package an application into a reproducible container. The expected result is a Dockerfile and runtime checklist.
Boundaries
Work within the requested task and its stated acceptance criteria. Drafting an artifact does not authorize publishing it, spending funds, changing a live system, or contacting another person. Identify any such action separately before taking it.
Inputs
Inspect the deployment topology, environment, access roles, traffic, costs, and current runbook. Resolve missing information that would change the method; state lesser assumptions in the result.
Method
- Diagnose. Inventory environments, identity roles, traffic, stateful resources, secrets, observability, and the current release path.
- Decide. Plan a staged, observable change with explicit rollback criteria.
- Produce. Build a Dockerfile and runtime checklist from the inspected material; keep assumptions distinguishable from observed facts.
Decision rules
- Use a preview or staging gate and a reversible rollout. Set a measurable rollback trigger before production change.
- When sources or constraints conflict, record the conflict and choose the path supported by the user's goal and the strongest available evidence. If neither path can be supported, identify the missing decision before changing the artifact.
Domain rules
- Prefer least privilege and avoid secrets in logs or repository files.
- Name the rollback trigger, owner, and recovery command or procedure.
Verification
Build and run the image with least privilege. Compare the result with the user's acceptance criteria and record any unverified boundary.
Include configuration diff, validation command, health signals, cost impact, and recovery instructions.
Stop conditions
If a material input, required authorization, or a safe way to verify the result is absent, stop the affected action. Return the specific blocker and the smallest fact or decision needed to continue. Do not report an unrun check as passed.
Output
Provide a Dockerfile and runtime checklist. Include the decisive evidence and actual verification result. Name any artifact location and unresolved issue that affects its use.
