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

With no annotations, the description carries the full burden. It only says 'value discarded', implying the input is not returned, but gives no other behavioral details: no side effects, no permissions, no return format, no error behavior. This is far below what a 9-parameter tool needs.

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 short (one clause), but conciseness without clarity is not valuable. It lacks structure, front-loading no actionable information, and the ambiguity makes it under-specified rather than efficiently concise.

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?

For a tool with 9 optional parameters, no annotations, no output schema, and no usage guidance, the description is wholly inadequate. An agent cannot determine what input to provide, what the output looks like, or how this differs from siblings. Nothing needed for correct invocation is present.

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. However, the description adds no connection between the parameters and the tool's function. It never indicates which of the 9 parameters is the pipe-separated input, and the parameter descriptions like 'discarded after the shape check' suggest a different purpose. The description fails to enrich any parameter semantics.

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 verb-like action (counting pipe-separated tokens) but fails to identify the resource or input. 'pipe-separated token count, value discarded' is a noun phrase that doesn't specify which parameter or what object is being counted. It does not distinguish from sibling tools like 'search-query-len' or 'memory-key-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 guidance on when to use this tool versus alternatives. There is no mention of context, exclusions, or conditions. The agent is left to guess from the sibling list, which provides no clarity.

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