Skill Backup

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description must carry behavioral disclosure. It states the action and destination path, but does not clarify whether backups overwrite existing copies, whether the operation is idempotent, how errors are handled, or whether the entire directory tree is copied. The output schema covers return values, but behavioral edge cases remain unstated.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single front-loaded sentence with a parenthetical rule. Every part earns its place: the operation, the destination pattern, and the mandatory timing are all stated without filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a low-complexity, 3-parameter tool with full schema coverage and an output schema, the description covers purpose, timing, and destination adequately. The only minor gap is richer behavioral detail about backup overwrite/idempotency, but the structured fields carry most of the remaining burden.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all three parameters, including defaults and examples. The description adds the backup path convention but no additional per-parameter semantics, so a baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description gives a specific verb ('备份' / back up) and resource ('技能目录' / skill directories), plus the destination pattern '~/.agents/skill-backups/<今天>/'. It is clearly distinguishable from sibling tools like skill_scan_corruption, skill_log_decision, skill_read_decisions, and skill_validate.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly states when to use it: before modification ('改前备份', '修订前必备份'), and frames this as an iron rule. There is no explicit when-not guidance or named alternative, but the timing condition is clear and actionable.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.