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

With no annotations, the description must carry the burden. It discloses that the query is discarded, which is useful, but it does not mention what the tool returns, how counting treats whitespace/unicode, or what happens if other parameters are supplied. For a simple read-only count tool this is partially adequate but incomplete.

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 short sentences with no filler. The core action and the discard behavior are front-loaded. It loses a point because the extreme brevity leaves the relationship between the description and the large input schema unexplained.

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?

Given nine optional parameters, no output schema, and zero annotations, the description is too thin to fully orient an agent. It does not state that only `query` is used, what the return format is, or why the other parameters exist. This is a clear completeness gap for a tool with this schema complexity.

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%, so the baseline is 3. The description adds meaning by clarifying that the operation is a character count on search-query text and that the query is discarded, but it does not reconcile the eight other schema parameters with this behavior.

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 specific action and resource: count characters in a search query. It is clear enough to distinguish this from URL/path/host checkers, though it does not explicitly mention the `query` parameter by name or address the other eight parameters.

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?

The description gives no guidance on when to use this tool versus alternatives, nor does it mention that only `query` is relevant while the other parameters are ignored. An agent might wonder whether to pass `url`, `json`, or `ref` because all are optional in the schema.

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