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

Mentions that the query is discarded, providing some transparency about side effects. However, it omits the core behavior of what is returned or how other parameters are handled (though the schema describes them as discarded). With no annotations, the description carries full burden, and this is insufficient.

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 concise sentences with no padding. The purpose is placed upfront, and the discard note is brief. It is efficient and easy to parse, though a few additional details could be included without harming conciseness.

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 is simple, but the description is missing the return value specification. It also does not explain why there are nine unrelated parameters, leaving the overall context incomplete for an agent deciding whether to call this tool and what to expect.

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 100% and each parameter has a descriptive comment, so the baseline is 3. The tool description adds no extra meaning to parameters beyond the schema; it only reinforces the query's purpose.

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 action ('Count characters in a search query') and the resource ('search query'), which is clear and distinct from sibling tools. However, it does not mention what the function returns (e.g., the integer length), slightly reducing clarity.

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?

No guidance on when to use this tool versus alternatives like 'memory-key-count' or 'hn-front-count'. The description is purely declarative and does not indicate conditions or scenarios where this tool is preferred.

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