glyphs-mcp-outlines-docs

Glyphs MCP outlines and docs

Use this skill for path editing, component or anchor work, selected-node workflows, cubic curve geometry and quality review, and bundled Glyphs docs lookup.

Core rules

• Prefer dedicated tools first.
• Use execute_code_with_context only for multi-step glyph-scoped work that is awkward with the dedicated tools.
• Keep any fallback script minimal, validate targets first, and bound output if needed.
• Use docs_search and docs_get instead of broad docs loading.
• Treat curve-quality results as measurements and conservative warnings, never as an artistic score or automatic pass/fail verdict.
• Use update_glyph_node_positions for explicit coordinate-only micro-edits on one glyph layer. Keep grid_policy="font" so the effective Glyphs grid, including subdivision or disabled rounding, is authoritative; use continuous only when the user explicitly requests off-grid precision.
• Before and after a node mutation, compare position, type, connection, smoothness, orientation, and name; only explicitly targeted fields may change.
• Treat a missing node name in set_glyph_paths as preserve and JSON null or "" as unnamed. In fallback Python, never assign None to a Glyphs string property such as GSNode.name; use "" when clearing it.
• The complete verified read-back from update_glyph_node_positions satisfies post-mutation verification. For other tools, re-read affected glyph state and stop if any non-target field changed.
• Never auto-save the font.

Workflow

1. Read the current state first with the smallest useful set:
   • get_selected_font_and_master
   • get_selected_nodes
   • get_glyph_paths
   • review_tunni_geometry
   • review_curve_quality
   • review_curve_quality_across_masters
   • get_outline_candidate_state
   • get_glyph_components
   • get_glyph_details
2. Prefer dedicated tools for the actual change:
   • update_glyph_node_positions
   • set_glyph_paths
   • add_component_to_glyph
   • add_anchor_to_glyph
   • apply_collinear_handles_smooth
   • review_tunni_geometry
   • apply_tunni_balance
   • review_curve_quality
   • set_curve_review_overlay
   • preview_tunni_balance_candidate
   • preview_collinear_handles_candidate
   • preview_italic_first_pass_candidate
   • preview_compensated_tuning_candidate
   • set_outline_candidate_overlay
   • get_outline_candidate_state
   • review_start_node_alignment
   • apply_start_node_alignment
   • materialize_outline_candidate_session
   • review_outline_candidate_session
   • accept_outline_candidate_session
   • discard_outline_candidate_session
   • preview_compensated_tuning_candidate only when that workflow is explicitly requested
3. Use candidate sessions for geometry-changing multi-master or multi-glyph batches. For start-node-only cyclic rotation, use the typed joint-alignment workflow below; never generate an execute_code_with_context rotation script. For Tunni work, pass explicit master/path/curve-end targets to preview_tunni_balance_candidate; keep grid_policy="font" unless the user explicitly requests continuous coordinates. Direct apply_tunni_balance remains compatible for one explicit target only.
4. Enable native Edit View review with set_curve_review_overlay(enabled=true, overlays=["curvature", "curve_events"]) after curve proposals and before mutation when visual judgment matters. Tell the user to inspect View > Show Glyphs MCP Curvature in Glyphs. Teal is positive signed curvature and pink is negative; curvature magnitude is placed along the path right normal, so correctly wound counters draw into their white interior. Event markers show extrema, inflections, cusps, and continuity warnings. Native comb defaults are 51 samples per cubic, a 0.010 scale, and a 0.12em normal clamp at 0.65 alpha. Use the control result to confirm activation; the Reporter measures raw editable paths only.
5. Review the difference-only Candidate Reporter before mutation. It leaves the normal Glyphs outline unobscured, draws only warm-yellow source/candidate difference regions, and turns those regions coral red when stale. If no manual edit is needed, call review_outline_candidate_session, dry-run acceptance, stop for approval, then confirm with the exact one-time token. If manual editing is wanted, dry-run and confirm materialize_outline_candidate_session, let the user edit the native layer, then re-review it. Never rely on LLM context to identify or delete candidate layers; use the persisted session metadata and discard_outline_candidate_session.
6. Only use execute_code_with_context when the edit spans several glyph-scoped steps and the dedicated tools would be less reliable or less clear.
7. When docs are needed, search first with docs_search, then fetch only the relevant page with docs_get.
8. After every mutation, compare all node fields listed above against the pre-mutation snapshot and report intended changes plus any unexpected difference. Use the node-position tool's complete verified read-back; otherwise re-read the affected glyph or layer. Treat an unexpected difference as a failed mutation even when the tool otherwise reports success.