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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile needs no restating. The description adds the notation convention (× separators) and sample designations, but says nothing about failure behavior for an unmatched designation, coverage of the catalog, or lookup constraints.

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?

Two tight sentences, one per language, with the property list and the format rules front-loaded before the examples. Slight duplication between the Chinese and English sentences, but no filler and nothing extraneous.

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?

Output schema exists, so listing the returned properties is optional rather than required, and the description nonetheless does so. Combined with the format examples, an agent has enough to invoke this single-parameter lookup correctly; only catalog coverage and mismatch handling remain unstated.

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 coverage is already 100%, so the baseline is 3, but the description goes further than the schema by spelling out the × separator convention and giving four family examples (HN, HW, L, C) that show the accepted shape syntax. This is genuinely additive because the correct delimiter and family prefix are failure-prone for an agent.

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?

States a specific verb+resource ('Look up full section properties for an exact GB designation') and enumerates the exact property set returned (A, Ix/Iy, Wx/Wy, ix/iy, kg/m). The word 'exact' implicitly distinguishes it from the sibling section_search, but no sibling is named explicitly, so differentiation is by inference rather than statement.

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?

The repeated emphasis on '精确型号'/'exact designation' implies this tool is for when the full designation is already known, which is useful context. However, it never states when-not to use it or names the alternative (e.g. use section_search when only partial dimensions are known), so the usage boundary is left to inference.

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