Conciseness

The body is dense with non-obvious, project-specific knowledge Claude cannot know (real role names like `conceptDeclaration` vs `applicableConcept`, the empty-default-suppresses gotcha, 'Older docs lie') and wastes no tokens explaining MPS basics. Minor trim candidates exist — the meta-level 'Loading companion skills' paragraph and the very long abstract-style Reference Index bullets — which fits 'efficient; minor instances of over-explanation that could be trimmed' rather than the every-token-earns-its-place anchor.

Actionability

Guidance is fully executable for an instruction skill: named MCP tools per step (`mps_mcp_insert_root_node_from_json`, `mps_mcp_check_root_node_problems`, `mps_mcp_alter_nodes` MAKE), naming templates (`<Concept>_ActionMap`, `<Concept>_<Position>_SubstituteMenu`), exact field and role names, smodel idioms (`node.replace with(...)`), and a copy-and-edit JSON blueprint reference. Per the rubric's scoring note, absence of inline code in an instruction-only skill is not penalized when guidance is this actionable.

Workflow Clarity

The 9-step Common-Path Workflow has a clear sequence with explicit validation checkpoints (step 7 `mps_mcp_check_root_node_problems` on every touched root), interactive testing (step 8), and an explicit feedback/diagnosis loop (step 9 `Ctrl+Alt+B`, plus the common-failures reference), matching the anchor for clear sequence with explicit validation and error recovery.

Progressive Disclosure

The Reference Index uses a consistent 'Open X when Y' routing pattern with a 'Start here — most common case' pointer to `references/landscape.md`; every reference is one level deep and each bullet states what the file contains so the reader can decide whether to open it. This matches the anchor for a clear overview with well-signaled one-level-deep references.

Specificity

The description enumerates concrete, specific artefacts and behaviors — action maps (`CellActionMapDeclaration`), cell keymaps (`CellKeyMapDeclaration`), transformation menus (`TransformationMenu_Default` / `_Named` / `_Contribution`), substitute menus, side transforms (LEFT/RIGHT), paste wrappers and copy-paste handlers, completion styling, reference presentation, two-step deletion, and the editor selection API — which is comprehensive coverage of the non-layout editor aspect, matching the top anchor rather than the 'minor gaps' anchor below it.

Completeness

It explicitly answers both questions: 'Use when authoring the **non-layout** parts of the MPS editor aspect — what happens when the user types, presses a key, triggers completion, pastes, or invokes a context action' gives the when, and the enumerated artefact list plus explicit trigger terms give the what, matching the anchor for clear and explicit what AND when with concrete trigger phrases.

Trigger Term Quality

An explicit trigger-term list provides both identifier forms users would actually paste (`actionMap`, `keyMap`, `delete_action_id`, `transformationMenu`, `substituteMenu`, `PasteWrappers`, `CopyPasteHandlers`) and natural-language synonyms and keystrokes (side transform, paste wrapper, completion styling, `Ctrl+Space`, `Ctrl+Alt+B`), giving comprehensive coverage including synonyms. This is the vocabulary an MPS editor-aspect task naturally surfaces, so it fits the top anchor rather than the 'a few natural terms missing' anchor.

Distinctiveness Conflict Risk

It carves out a clear niche (non-layout editor aspect only) and draws an explicit boundary — 'For the **layout** side (cells, layouts, style sheets) use `mps-aspect-editor` instead' — which minimizes overlap with the neighboring editor-aspect skills. Distinct technical triggers like `delete_action_id` and `PasteWrappers` are unlikely to fire for the wrong skill, matching the 'clear niche with distinct triggers' anchor.