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

The description discloses that the query is discarded, but it does not mention that other parameters are also discarded (as indicated in the schema descriptions) or describe the return value. With no annotations, the description carries the full burden and fails to disclose behavior for the other eight parameters or the output format.

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 extremely brief with only two sentences, but this brevity is not appropriate because it omits essential information about the tool's scope and behavior. It is not front-loaded with the most critical context beyond a single action.

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 nine optional parameters and no output schema, the description is grossly incomplete. It fails to explain the purpose of the other parameters, what the tool returns, or any side effects. An agent cannot reliably use this tool without additional context.

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 descriptions for all nine parameters, so the baseline is 3. The tool description adds minimal value beyond the schema, only mentioning the query parameter and ignoring the others. It does not clarify how the parameters relate to the action, which could mislead an agent into thinking only query is used.

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 the action 'Count characters in a search query' with a clear verb and resource. However, the input schema includes nine other parameters that are not mentioned, creating ambiguity about whether the tool counts characters in only the query field or in any provided string. This mismatch undermines clarity and does not differentiate from siblings like memory-key-count or hn-front-count.

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 is provided on when to use this tool versus alternatives. There is no mention of prerequisites, exclusions, or conditions that would help an agent choose between this and similar counting tools.

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