Conciseness

The body is dense and mostly lean, but the slides-skill pointer appears twice (intro and the editor:'slides' line) and the 'Show the result' section restates the open-early rule in overlapping forms ('establish a meaningful renderable checkpoint early' vs 'Open only when the manifest references at least one existing, renderable document'), matching anchor 4.

Actionability

Fully executable guidance: a copy-paste-ready manifest JSON with concrete layout values, an exact shell pattern ('cp <scratch>/image-….png <board>.canvas/outputs/hero.png'), explicit tool calls (read_file, write_file, surface_open with a workspace-rooted path), and precise field semantics covering the common cases.

Workflow Clarity

Clear sequence (make the bundle folder first → write .canvas.json → write documents → surface_open early → continue) with explicit validation checkpoints: re-read .canvas.json before editing to avoid clobbering, never open an empty bundle or broken manifest, and preserve version/$schema/editor and unknown fields on rewrite.

Progressive Disclosure

No bundle files exist and none are needed; the body inlines only overview-appropriate material (a short manifest example, not an API dump) with no buried or nested references, and its three sections (Structure / Working pattern / Show the result) are easy to navigate.

Specificity

Concrete domain ('Author and edit a Grida `.canvas` board', 'manifest plus document files (references, generated images, notes)') but the action verbs stop at author/edit; the remaining detail describes format rather than a fuller action set, matching anchor 4 rather than 5.

Completeness

Explicitly answers both what ('Author and edit a Grida `.canvas` board — a `.canvas.json` manifest plus document files...') and when ('Use when working on a `.canvas` bundle or arranging visuals/design work spatially'), with concrete trigger phrases plus a boundary clause — the anchor 5 example.

Trigger Term Quality

Good natural keywords including the file extension ('.canvas', 'board', 'infinite canvas', 'arranging visuals/design work spatially', 'deck/presentation'), but a few common user phrasings (e.g. moodboard, layout, arrange images) are missing, so anchor 4 fits better than 5.

Distinctiveness Conflict Risk

Clear niche (Grida `.canvas` boards) with explicit disambiguation ('For a linear deck/presentation, use the `slides` skill instead'), giving distinct triggers and minimal conflict risk.