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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and a closed world, so the safety profile is covered. The description adds no further behavioral context such as output shape, language handling, or limits, so it only marginally exceeds the annotation baseline.

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?

One tightly packed sentence with the operations front-loaded and no filler; every clause names a distinct computation the tool performs.

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?

With an output schema present, return values need not be explained, and the description enumerates the computed metrics well. The remaining gap is the absence of any routing hint against the sibling character_count for overlapping use cases.

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?

There is a single required parameter, text, and the schema's own description for it is empty (0% coverage). The phrase 'from text' confirms the input is raw text, but no guidance on format, length, or edge cases is added, so it only partially compensates for the empty schema description.

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 gives a specific verb (count/estimate) plus the exact outputs (words, characters, sentences, paragraphs, reading and speaking times) drawn from text. It is clear what the tool does, but it does not differentiate itself from the closely related sibling character_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?

There is no when-to-use guidance, no prerequisites, and no mention of the overlapping sibling character_count, which an agent could easily pick instead if it only needs character totals. Usage is only implied by the input type.

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