text_stats

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

No annotations are provided, so the description must convey behavior on its own. It does so by listing the exact statistics returned, which is the core behavior. It does not mention edge cases or side effects, but for a counting tool, this list is sufficient and adds context beyond the basic tool name.

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 sentence that efficiently lists the metrics, with no filler. It is front-loaded with '字数统计' and immediately enumerates the results, earning its place with every word.

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?

The tool has one simple parameter and no output schema. The description covers what the tool returns, which is the main requirement. It is concise and sufficient for an agent to select and invoke this tool, though it does not mention any additional behavior such as how newlines are counted, which is not critical for a basic text statistics tool.

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?

The schema provides only the parameter name 'text' with a type string and no description. The tool description does not explicitly explain the parameter, but the phrase '字数统计' makes it clear that the input text is the content to be counted. Since the schema coverage is 0%, the description compensates implicitly but not explicitly.

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 clearly states the tool performs text statistics and enumerates the specific metrics (total characters, Chinese characters, letters, digits, spaces, punctuation, lines, word count). This makes the tool's purpose obvious and distinguishes it from sibling text-processing tools like text_filter or text_replace.

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 description does not explicitly provide usage guidance, such as when to use this tool versus other text tools. The only usage signal is the implicit one from the tool's function, so it is adequate but lacks explicit alternatives or exclusions.

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