name: pencil-swiftui-design-rule-mapper description: Map Pencil MCP design tokens and reusable components to enforced SwiftUI coding rules. Use when generating or refactoring SwiftUI from .pen-based designs and you must enforce naming conventions, spacing tokens, typography tokens, and accessibility labels/identifiers with lintable checks.

Pencil SwiftUI Design Rule Mapper

Workflow

1. Extract design sources of truth from Pencil.

• Call mcp__pencil__get_variables for design tokens.
• Call mcp__pencil__batch_get with patterns: [{"reusable": true}] to collect reusable components.
• Stop and ask for clarification if tokens or reusable components are missing.

2. Create the mapping manifest before editing SwiftUI.

• Copy references/mapping-manifest.template.json to a project-local manifest.
• Fill component_name_map from Pencil component names to SwiftUI type names.
• Confirm token prefixes in code (spacing_token_prefixes, typography_token_prefixes).
• Set component_struct_suffix (default View) for reusable component structs.

3. Apply enforced SwiftUI rules.

• Naming:
• Use PascalCase for reusable component structs.
• End reusable component structs with component_struct_suffix.
• Use component_name_map aliases when Pencil names contain spaces or /.
• Spacing:
• Do not use raw numeric literals in .padding(...) or spacing:.
• Use spacing tokens only (Spacing.* or configured prefixes).
• Allow numeric spacing only when explicitly listed in allowed_numeric_spacing_values.
• Typography:
• Do not use .font(.system(...)) or .font(.custom(..., size: ...)).
• Use typography tokens only (Typography.* or configured prefixes).
• Accessibility:
• Require explicit .accessibilityLabel(...) for Button, Toggle, TextField, SecureField, and Image.
• For decorative images, allow .accessibilityHidden(true) instead of label.
• Require .accessibilityIdentifier(...) for interactive controls when a11y_require_identifier_for_interactive is true.

4. Enforce with deterministic audit.

• Run scripts/swiftui_rule_audit.py --manifest <manifest.json> --paths <swift file/dir ...>.
• Treat exit code 1 as a hard block unless the user accepts an explicit waiver.

5. Report with traceability.

• Group fixes by naming, spacing, typography, and accessibility.
• Include file/line references and rationale for any accepted waivers.

Execution Notes

• Iterate in short loops: audit -> patch -> audit.
• Keep the manifest as the contract between design and code.
• Prefer local/offline checks only.

Resources

scripts/swiftui_rule_audit.py

Run lint-style enforcement for naming, spacing, typography, and accessibility rules.

references/mapping-manifest.template.json

Start each project mapping contract from this template.