Conciseness

The body is dense domain policy with no filler or explanation of known concepts, but key rules are systematically duplicated — 'the first Content is automatically main' appears ~6 times (Ground rules, Capabilities, Confirmation, add_canvas_contents, select_canvas_main_content, Workflow coverage) and timeout/retry semantics ~5 times. This goes beyond anchor 4's 'minor instances that could be trimmed' while stopping short of anchor 2's padded sections.

Actionability

Every one of the 13 tools gets an executable, copy-paste-ready snippet with the required import shown once, parameter tables with required/optional flags, exact field names, and realistic example values (e.g. the add_canvas_elements items payload and the design-marker reference_images example). Fully matches anchor 5.

Workflow Clarity

Multi-step flows are explicitly sequenced (7-step media-transformation pattern, 4-step marker processing) with hard validation checkpoints: the mandatory preflight before every write, re-query after writes, staged user-confirmation gates, bounded retry gated on explicit status=failed with a 2-attempt cap, and post-import verification via query_canvas_element_details. This is the anchor-5 pattern of sequence + validation + feedback loops.

Progressive Disclosure

All 9 referenced files exist, and the Reference routing section plus Tool map clearly signal one-level-deep conditional loading. However, the ~600-line main file inlines deep detail that overlaps existing references — notably the ~250-word audioPolicy edge-case paragraph and the final-composition section, which duplicate territory of references/video-generation.md — a minor organization gap that keeps it at anchor 4 rather than 5.

Specificity

Lists six or more concrete actions ('initialize and query projects, create Elements and Content candidates, frame Elements, wait on generation, and process design markers') and the routing sentence names the remaining capabilities, leaving no material coverage gaps — matching the anchor-5 example's comprehensiveness rather than the 'minor gaps' of anchor 4.

Completeness

Explicitly answers both 'what' (the concrete action list) and 'when' (a 'Use when...' clause with concrete trigger phrases plus quoted example utterances), which is exactly the anchor-5 pattern; it is not anchor 4 because the 'when' guidance is fully explicit rather than merely present.

Trigger Term Quality

Beyond domain nouns (images, videos, storyboards, video edits, final composed video), it quotes four verbatim user utterances ('generate an image on my canvas', 'make a video from this canvas project', 'add a new element to my design', 'edit the marked region of this image') — comprehensive natural-phrase coverage including marker syntax, fitting anchor 5.

Distinctiveness Conflict Risk

The niche (a Canvas product managed through its business tools) is distinct, and the unique [@design_canvas_project:...] / [@design_marker:...] tokens plus canvas-scoped quoted utterances give minimal conflict risk with generic image/video skills — anchor 5 rather than 4's 'minor overlap risk'.