Conciseness

The body is lean instruction-only prose with no padding and no explanation of concepts Claude already knows — every rule adds proprietary system knowledge (limits, layout, index semantics). Only one minor restatement (the 10-entry listing limit appears in both "Write the indexes" and "Design for progressive disclosure") keeps it from being a textbook anchor 5, but it still fits best.

Actionability

Guidance is concrete and executable throughout: exact path ($MEMORY_DIR/.memfs.config.json), exact config fields with defaults and depth examples, a copy-paste frontmatter block, a layout tree, link syntax ([Acme](projects/acme.md)), and sharp decision rules. For an instruction-only skill this matches the fully actionable anchor 5.

Workflow Clarity

The sections form a coherent order ("Check the limits first" → layout → indexes → design) and include two genuine validation loops (trace the discovery path and "fix the index"; split or flatten when content exceeds limits). It stops short of anchor 5 because the process is never laid out as an explicit sequenced workflow — the reader must infer the order from section arrangement.

Progressive Disclosure

No bundle files exist, and none are needed: at ~80 lines of tight, on-task guidance there is no bulk content that belongs in separate files, and the body is cleanly sectioned with informative headers. This fits the well-organized, no-external-references-needed top anchor.

Specificity

The description names the domain ("Maintains deferred memory") and what it holds ("accumulated knowledge, analysis, and observations"), but these are 1-2 domain-level actions rather than a list of several specific operations. It sits at anchor 3: not vague like anchor 2, but lacking the multi-action coverage of anchor 4.

Completeness

Both what ("Maintains deferred memory, which stores accumulated knowledge, analysis, and observations") and when ("Use when saving knowledge...") are explicitly stated with concrete trigger examples, matching the anchor 5 pattern including negative triggers. Anchor 4 would require the when-clause to be less explicit than it is.

Trigger Term Quality

"Use when saving knowledge (e.g. about a person, project, repository, system, or event)" supplies several natural trigger terms users would actually say. It falls short of anchor 5 because common synonyms like "remember", "notes", or "recall" are missing.

Distinctiveness Conflict Risk

The explicit "Do NOT use for managing skills, prompts, or for saving information that is already automatically stored in the message history" carve-outs reduce conflict risk substantially, but the positive trigger "saving knowledge" still overlaps with closely related note-taking or memory skills. Mostly distinct with minor overlap risk — anchor 4, not 5.