面试题库

分析过程 · 先想清楚再作答

1. 这题考的是「上下文成本意识」。答成「CLAUDE.md 放规则、skill 放流程」只是结论，面试官想听你从加载方式推出这个结论。
2. 拆法从加载时机入手：CLAUDE.md 每次会话整份进入上下文，是固定成本；skill 只有描述那一行常驻，正文在被触发（模型判断相关或用户输入 /name）时才加载，是按需成本。所以「每次都成立的短事实」放 CLAUDE.md，「偶尔才用、一用就是多步」的流程放 skill。
3. 给判据表：命令、风格差异、仓库礼仪、环境怪癖、完成的判据进 CLAUDE.md；部署流程、修 issue 的固定步骤、某类文档的生成方法进 skill。反过来，CLAUDE.md 里出现了多步流程，或 skill 里放了「每次都要遵守」的规则，都是放错了。
4. 500 行的问题不是「太长跑不动」，而是稀释：重要规则被淹没，模型的遵守度反而下降，还白白吃掉每轮的窗口。对策是「删到不能再删」（删掉会不会让它犯错？不会就删）、把偶尔用的挪进 skill、按路径拆进 .claude/rules/ 只在碰到匹配文件时加载。
5. 可预期的追问：「规则它老是不听怎么办」——先删再改再强调；「必须每次执行」的动作根本不该靠 CLAUDE.md，要改成 hook。

How to reason about it · think before answering

1. This tests context-cost awareness. 'CLAUDE.md holds rules, skills hold procedures' is the conclusion; derive it from how each is loaded.
2. Start from load timing: CLAUDE.md enters context in full every session — a fixed cost; a skill keeps only its one-line description resident and loads its body on invocation — a variable cost. Hence short facts that always apply go in CLAUDE.md, occasional multi-step procedures go in skills.
3. Give the table: commands, non-default style, repo etiquette, environment quirks, and the definition of done belong in CLAUDE.md; deployment runbooks, issue-fixing steps, document generators belong in skills. Multi-step procedures in CLAUDE.md or always-on rules inside a skill are both misplacements.
4. At 500 lines the failure is dilution, not capacity: important rules drown, adherence drops, and every turn pays for the bloat. Fixes: prune ruthlessly (would removing this cause a mistake?), move occasional content to skills, split path-scoped rules into .claude/rules/ so they load only when matching files are touched.
5. Follow-ups: a rule that keeps being ignored — prune, then disambiguate, then emphasize; anything that must run every time should be a hook, not a sentence.

分析过程 · 先想清楚再作答

1. 这题考的是抽象层次的区分，是国内面试开始高频出现的「Function Call / MCP / Skills 三者区别」的工具侧版本。
2. 拆法是问「加的是什么」：加的是访问外部系统的能力（查工单、读数据库、调内部服务）就是 MCP，它是协议层的工具；加的是一套多步骤的做法（发版检查、迁移流程）就是 skill，它是提示词层的流程包；每次会话都要遵守的约定就是项目说明文件。
3. 再给触发方式的差别：MCP 工具由模型在需要数据时调用；skill 由用户显式点名或由模型按描述匹配；说明文件每次会话开头无条件读入。
4. 结论落到一句话：规矩归说明文件、外部系统归 MCP、流程归 skill；同一件事只放一处，避免三处互相矛盾。
5. 可预期的追问：skill 里能不能调 MCP 工具？可以，skill 的步骤里可以要求使用某个工具，两者是正交的层次，不是替代关系。

How to reason about it · think before answering

1. This tests separation of abstraction levels, the tooling-side version of the increasingly common 'function calling vs MCP vs skills' question.
2. Ask what is being added: access to an external system (tickets, databases, internal services) is MCP, a protocol-level tool; a multi-step procedure (release checklist, migration flow) is a skill, a prompt-level workflow package; conventions to obey every session belong in the instruction file.
3. Contrast triggers: MCP tools are invoked by the model when it needs data; skills are invoked explicitly by name or matched by description; instruction files are loaded unconditionally at session start.
4. Conclude: rules in the instruction file, external systems via MCP, procedures as skills; keep each fact in one place to avoid contradictions.
5. Expect the follow-up: can a skill use MCP tools? Yes; a skill's steps can call for a tool, the layers are orthogonal, not substitutes.