Conciseness

Every line is dense, skill-specific operational fact — e.g., "history 是端到端加密的占位消息", "--limit 不扩展上游范围", "超时/断连先核对结果，不换通道重发" — with no padding and no explanation of concepts Claude already knows. The E2E-encryption note is non-obvious tool-specific behavior, not general knowledge, so it fully earns its tokens.

Actionability

Concrete executable commands are given (`twitter-im list --limit 20`, `twitter-im history "<会话ID>" --limit 20`, `x-hunter login/export`) with concrete flags (`--account`, full ID as string). It stops short of score 5 because `twitter-im call <resource> <action>` has no concrete example and the referenced 工具能力表 (capability table) is not included, so the actual resource/action values are not discoverable from the skill.

Workflow Clarity

The sequence is clear (login via `x-hunter login/export` → list → history → optional call) and validation checkpoints are present: "仍须本地实号验证响应、送达与权限" and "超时/断连先核对结果，不换通道重发" plus recording requirements. It misses score 5 because the ordering is implied by paragraph order rather than an explicit sequence, and recovery after a failed verification (what to do once a timeout result is checked) is not closed into a full feedback loop.

Progressive Disclosure

The skill is under 50 lines, self-contained, and appropriately sized with no bloated inline content; the cross-reference to `x-hunter` for content collection correctly routes a sibling capability elsewhere. It misses score 5 because the flat layout has no section headers or signposting to separate capabilities/limits, commands, and verification rules, which would make the short document easier to navigate.

Specificity

Only "X/Twitter私信会话" names the domain; "支持范围以工具能力表为准" defers capabilities to an external 'tool capability table' instead of naming any concrete action (list, read history, etc.). It is above score 1 because a specific domain is named, but below score 3 because zero concrete actions are stated in the description itself.

Completeness

The 'what' is vague — the actual capability scope is delegated to the 工具能力表 rather than stated — and the 'when' (any 'Use when...' trigger guidance) is entirely missing, matching the 'vague what and no when' anchor. It cannot reach score 3 because even the 'what' never states a concrete capability, and there is no weakly implied 'when' at all.

Trigger Term Quality

The terms "X/Twitter" and "私信" (DMs) are natural phrases users would say, so this sits at the 'some relevant keywords but missing common variations' anchor. It misses score 4 because synonyms like 'DM', 'direct message', '消息', or '发消息' are absent, yet it is above score 2 because the keywords present are domain-natural rather than generic.

Distinctiveness Conflict Risk

"X/Twitter私信会话" carves out a clear niche (DM conversations on X/Twitter) with minimal overlap risk against unrelated skills. It falls short of score 5 because the reference to a 工具能力表 implies a sibling family of X/Twitter tools (e.g., the x-hunter scraping skill referenced in the body), creating minor overlap with closely related skills.