Count words and characters

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered structurally. The description still adds value beyond them by disclosing that the result set includes a derived reading-time estimate — output information the agent cannot get from annotations or an output schema (none exists). It stops short of saying how reading time is derived (e.g., words per minute).

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 front-loaded sentence listing what is measured before the add-on (reading time). Every clause earns its place with zero filler or restatement of the title.

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 one-parameter, read-only utility with annotations covering safety and no output schema, the description is essentially sufficient — it enumerates every value returned. The only gap is that reading-time estimation basis (words per minute) and text handling edge cases are unstated.

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' with 0% schema description coverage, so the description must carry the burden. It says the counting happens 'in text', which confirms the parameter's role, but adds no detail on encoding, size limits, or how multi-byte/unicode characters are treated.

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 names a precise verb (count) and enumerates the exact units measured: words, characters, sentences, paragraphs, plus an estimated reading time. No sibling tool overlaps with counting, so there is nothing to disambiguate from — an agent immediately knows what this does.

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?

Usage is only implied: it's a self-evident utility that any agent would call when text metrics are wanted. There are no explicit when/when-not statements, no prerequisites, and no named alternatives (none exist among the siblings), so it lands at minimum-viable rather than strong.

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