Skill App Creator

Build a skill that operates like a small application: the agent handles judgment, helpers handle repeatable mechanics, and users receive predictable deliverables. Keep output structure stable; let conclusions, uncertainty, and supported precision vary with the evidence. “Skill-app” is a design convention within the Agent Skills format, not a separate host capability.

Use skill-creator for skill structure, routing, scaffolding, and repository validation. This skill adds application contracts and runtime design. In malskill, build support apps only when they improve an active security workflow.

Establish the application contract

Inspect existing skills and actual helpers before designing new components. For an existing app, trace one input through stored state to delivery; preserve working commands and data unless the requested change requires migration.

Complete assets/app-contract.md when designing an app or changing its input, output, or lifecycle contract. Keep the filled contract in the working project; publish only the rules, schemas, and templates the resulting skill needs.

Decide before implementation:

• The recurring user action, accepted inputs, and smallest useful deliverable.
• Exact output filenames, fields or sections, units, ordering, and unknown values. A user-requested format overrides defaults without erasing verification status.
• What the agent decides, what scripts calculate or validate, and which evidence supports success.
• Required dependencies and optional capabilities; offline behavior, external uploads, configuration precedence, and cost limits.
• How invalid inputs, partial results, interruptions, and unresolved tasks appear. Never require an invented value just to satisfy a success schema.