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

There are no annotations, so the description carries the full burden of behavioral disclosure. It does disclose that the query is discarded, which is a useful side-effect hint. But it says nothing about return values, whether other accepted parameters have side effects, or why the schema describes 'shape check' behavior that the description never acknowledges. Transparency is only partial.

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 short and front-loaded with no filler, and each sentence carries information. However, for a tool with nine optional parameters and no annotations or output schema, it is under-sized and omits necessary scope, so it is not appropriately sized. This is conciseness at the cost of completeness rather than effective efficiency.

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 context is complex: nine optional parameters, no annotations, and no output schema. The description fails to mention eight of those parameters, does not state what the tool returns (e.g., a number or validation status), and leaves the mismatch between 'count a search query' and the URL/city/JSON/host fields unresolved. An agent cannot confidently select or correctly invoke this tool based on this definition.

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 description coverage is 100%, so the baseline is 3. The description adds no per-parameter meaning beyond the schema; it only refers to the query concept while ignoring the eight other documented parameters. Since the schema already describes each parameter sufficiently, the description need not compensate, but it also contributes nothing extra.

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 concrete action ('Count characters in a search query') and one behavior ('Query discarded'), so it is not a mere restatement of the name. However, it is misleadingly narrow: the input schema exposes eight other heterogeneous parameters (url, city, feed, json, path, zone, host, ref) and the description never explains their relationship to the tool. It also does nothing to distinguish this tool from similar count/check 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 when-to-use, when-not-to-use, prerequisite, or alternative guidance is provided. The only inferred usage is that this tool is for measuring search-query length, which is implied by the name rather than explicitly recommended. Given the long sibling list, an agent receives no help choosing this tool over related checking tools.

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