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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower. The description still adds real behavioral value: it discloses that it returns Chinese text plus official English only when the Ministry published a translation (explicitly never a machine translation), and includes the chapter/section heading.

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?

Front-loaded with the core action, then the accepted article spellings, then return content, then the routing caveat. Dense but every clause earns its place with no 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?

With no output schema, the description carries the return-value burden and does so thoroughly (Chinese text, official English, chapter/section heading, and the guarantee of single-article scope). Combined with annotations covering the safety profile, an agent has everything needed to call it correctly.

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 name, pcode and article. The description's 'any spelling' examples and pcode-vs-title guidance largely restate the schema fields rather than adding new semantics, so the baseline 3 applies.

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 ('Full text of ONE article (條) of a Taiwan law') and immediately distinguishes itself from siblings by naming tw_law_toc and clarifying that a long law is never returned whole. An agent can tell it apart from tw_law_search/tw_law_toc/tw_law_info without opening any schema.

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?

Explicitly routes the agent: 'use tw_law_toc to find article numbers, and call this once per article,' and warns that a long law is never returned whole. It names the alternative and the operating cadence, though it stops short of stating explicit when-not conditions.

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