Conciseness

At roughly 28 lines the body is lean and efficient with zero padding: "Use this package for messages to a person... The caller owns authority, delivery and report schedules" assumes Claude's competence and every token earns its place. No explanation of concepts Claude already knows.

Actionability

The guidance is fully executable: an unconditional step ("Read [messages](references/messages.md) before every message"), a task-to-reference routing table with exact paths, and copy-paste-ready install lines ("Before writing a message to a person, read `.agents/skills/communication/SKILL.md`."), covering the common cases.

Workflow Clarity

A simple skill with an unambiguous workflow: one mandatory read followed by at most one conditional read selected from the routing table ("Add only the reference the task needs"). No destructive or batch operations exist, so no validation checkpoints are required under the simple-skill exception.

Progressive Disclosure

Verified against the actual bundle: the body is a clear overview with four well-signaled one-level-deep references (messages.md, questions.md, reports.md, voice.md), all of which exist on disk. Content is appropriately split and the routing table makes navigation easy; reports.md's link to messages.md is a same-level cross-link, not nesting.

Specificity

"a reply, report, briefing, decision request, or issue or comment" enumerates five concrete message types, matching the anchor for several specific items with minor gaps. Not 5 because it never states what the skill does with those messages (e.g. plain-language writing guidance); not 3 because it goes well beyond 1-2 concrete items.

Completeness

The when is explicit and concrete ("Load before writing a message to a person: a reply, report, briefing...") but the what is only implied through the enumerated message types — the skill's actual capability is never stated. Fits 'both present, one could be more explicit' better than the anchor-5 pattern of explicitly answering both.

Trigger Term Quality

Natural terms users would say — "reply", "report", "briefing", "decision request", "issue or comment", "message to a person" — give good keyword coverage. A few natural terms are missing (e.g. "email", "response", "answer", "update"), keeping it below the comprehensive-synonym anchor of 5.

Distinctiveness Conflict Risk

"message to a person" and "addressed to the user" carve a clear niche distinct from agent-to-agent messages, return formats, tool prompts, and documentation. Trigger phrases are distinct and the wrong-skill overlap risk is minimal.