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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description's added value is disclosing the content of the report (per-objective attribution, level comparison, gap flags, and a suggested rewrite), which is useful since there is no output schema, but it says nothing about output structure or length.

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 purpose and check list are front-loaded in a single dense sentence, and the input requirement follows. The trailing English sentence largely duplicates the Chinese opening, but it is short and aids routing.

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?

With no output schema, the description carries the burden of describing what comes back, and it does so by enumerating the check results and the rewrite. It is complete enough for correct invocation; only the response shape (per-objective list vs. summary) remains unspecified.

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 defines all five parameters. The description only restates which inputs to supply and hints that topic or codes can anchor the comparison, adding little beyond what the schema text already says (codes optional, '按这些对照').

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 uses a specific verb+resource (逐条对照课标要点体检 a teacher's already-written learning objectives) and enumerates the exact check dimensions: which standard point, which characters of the original text, whether the level is higher/lower, missing condition/behavior/degree, plus a rewrite. This enumeration makes it unmistakable versus lookup siblings like get_standard or search_standards.

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 clearly scopes the input situation — objectives the teacher has already written, plus subject, grade and topic (or code) — which tells an agent when this tool applies. It does not explicitly say when not to use it or name the alternative (e.g. use get_standard to look up the text first), so it stops short of full routing guidance.

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