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

With no annotations, the description carries the full burden of disclosing side effects. It states the query is discarded, which suggests no persistence, but it does not mention return format, error behavior, or that unrelated schema parameters are ignored.

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 and immediately states the core action and a key side effect. It is front-loaded and free of unnecessary detail.

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 a deceptively large schema with multiple optional parameters, yet the description does not explain that only the query parameter is used or how the other parameters should be handled. The lack of output schema information also leaves the return value unspecified.

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?

Although schema coverage is 100%, many parameter descriptions reference unrelated concepts (URLs, city names, JSON validation, file paths) that do not align with counting characters. The query parameter description is relevant, but the overall schema is confusing about which parameters actually affect the operation.

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 counts characters in a search query, giving a specific verb and object. It could more explicitly tie the query parameter to the main action, but the purpose is understandable.

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 sibling tools that also deal with counts or validation. The description does not explain the intended context or alternative selection criteria.

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