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

The description discloses the important behavior that the query is discarded, which suggests no persistence and helps the agent understand side effects. With no annotations present, the description carries much of the transparency burden, but it omits any mention of return value, error cases, or limits. It is not misleading, but it is thin.

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 concise and front-loaded: the purpose appears in the first sentence, and the disposal behavior in the second. There is no wasted text, every sentence adds information, and the structure is easy to parse.

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 description is too incomplete for an agent to invoke this tool safely or correctly. The schema's seven parameters appear unrelated to the described 'search query' behavior, there is no explicit return-value description, no output schema, and no clear indication of which parameter should be passed. For a simple tool this could have been sufficient with matching parameters, but the mismatch makes the overall context incomplete.

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 input schema lists seven string parameters, each with its own description, but none is labeled as a search query. The tool description says to count characters in a search query, yet it never explains which parameter supplies that query or how the parameters relate to the described behavior. Since schema description coverage is high, the baseline would be 3, but the semantic mismatch between the tool description and the parameters reduces the practical value to 2.

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 a specific action: count characters in a search query, and adds that the query is discarded. This distinguishes it from many sibling tools by naming the resource ('search query') and the operation ('count characters'). However, it does not explicitly differentiate it from similar counting tools like memory-key-count, and it conflicts with the schema by never identifying which input parameter represents the query.

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. The description does not mention exclusions, prerequisites, or alternative tools such as validate-json or normalize-url. An agent has no context to decide whether this is the right tool for a given search-related task.

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