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

With no annotations, the description carries the full burden. It discloses that the query is discarded, which is useful, but it remains silent on the fate and handling of the other 8 parameters. The schema descriptions mention some discard behavior, but the tool description does not synthesize that. It also does not state the return value or any side effects, leaving major behavioral gaps.

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 short sentences), which is good for front-loading the core action. However, it is under-specified, omitting crucial information about the tool's broader behavior. Conciseness is not the same as completeness; this leans toward oversimplification.

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 9 optional parameters, no annotations, and no output schema, the description is far from complete. It only covers the query parameter, leaving the purpose and handling of the other parameters unexplained. An agent would need to inspect the schema to understand the tool's full capabilities, which the description should have summarized.

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 minimal value beyond the schema, only referencing the query parameter. It does not mislead, but it fails to highlight that other parameters are also validated or discarded. Since the schema already documents each parameter, the description does not need to repeat, but it could have added context on how parameters interrelate.

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 verb and resource: 'Count characters in a search query.' This is specific and aligns with the tool name. However, it does not explain the other 8 parameters in the schema, so the full scope of the tool is unclear. It partially distinguishes from siblings like memory-key-count by focusing on search queries, but lacks explicit differentiation.

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 provides no guidance on when to use this tool versus alternatives. There is no mention of context, prerequisites, or exclusions. An agent has no clue whether this tool is preferred over shape-checking siblings or when to pick it.

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