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

With no annotations, the description carries the full burden of behavioral disclosure. It only states 'Query discarded,' implying no persistence of the query, but says nothing about the fate of the other parameters, potential side effects, or what the tool actually does with them. Given the tool accepts 9 parameters, this is a significant transparency gap.

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 (two sentences) and front-loads the primary purpose. Each sentence is functional: one states the action, the other states a side-effect. However, the brevity comes at the cost of missing essential information, which is a trade-off, but for conciseness itself it is well-structured.

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 the tool has 9 optional parameters, no output schema, and no annotations, the description is severely incomplete. It does not explain what happens with the other parameters, what the return value is (presumably a character count, but not stated), error conditions, or any edge cases. An agent cannot correctly invoke this tool for non-query parameters without additional information.

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 100% coverage, describing each parameter individually. The description adds little beyond the schema, only implying that 'query' is the parameter being counted. It does not clarify the role of the other 8 parameters or how they interact, so it fails to add meaningful semantic value beyond what the schema already offers.

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 clear action ('Count characters in a search query') and identifies the resource (search query). However, it fails to acknowledge the other 8 parameters in the schema, making the tool's actual scope ambiguous. It also does not differentiate it from sibling tools like memory-key-count that also count characters, so the purpose is only partially clear.

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 on when to use this tool versus alternatives, no mention of conditions or prerequisites, and no exclusions. The description does not indicate that it is specifically for search query length checks or how it relates to other shape-check tools, leaving the agent without clear selection criteria.

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