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

No annotations are present, so the description carries the behavioral disclosure burden. It does disclose that the query is discarded, which signals no persistence and a read-only operation. However, it does not state the return value, behavior with empty input, or how multiple supplied parameters are handled, leaving the behavior only partially transparent.

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 two short sentences with the purpose front-loaded and no filler. The discard note is a useful behavioral addition. It is appropriately sized for a simple utility tool.

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 tool with nine optional parameters and no output schema, this description is too sparse. It does not explain what the tool returns, which parameter is the search query, or whether the extras are acceptable, relevant, or should be omitted. An agent could call it with the wrong parameter or miss that it returns a length value.

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 every parameter individually. The description adds no new parameter semantics beyond referencing 'search query' and 'query discarded,' and it does not clarify why eight unrelated optional parameters exist or whether only the 'query' parameter should be passed.

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 states a concrete operation: count characters in a search query. This is reasonably distinct from sibling URL, weather, fetch, and validation tools. It could be clearer that the relevant input is the 'query' parameter among the nine optional parameters, but the verb and resource are specific.

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?

There is no guidance about when to use this tool versus alternatives. Sibling tools are not mentioned, and no selection conditions or exclusions are provided. An agent must infer that this tool is for search-query length checks rather than, for example, counting tokens or counting memory keys.

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