count_pages

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

With no annotations, the description must carry the behavioral burden; 'estimate' usefully connotes a non-destructive, approximate calculation rather than an exact guarantee. However, it does not disclose what happens if the artifact is not rendered, what characters-per-page default is used, or what the return value looks like.

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?

A single seven-word sentence with no filler; the core operation is front-loaded and the description is appropriately sized for a simple parameter-light tool.

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 two-parameter tool with no output schema or annotations, this is adequate but thin: it implies a page count is returned but never states the return format, default behavior when chars_per_page is omitted, or error conditions. A sentence on output and defaults would make it complete.

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 schema already documents both parameters. The description does not add meaningful detail about defaults, units, or how chars_per_page affects the estimate, so it stays at the baseline.

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 has a clear verb ('estimate'), a clear output object ('page count'), and a scoping phrase ('for a rendered artifact'). This is enough to differentiate count_pages from render_markdown, verify_delivery, and ship.

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 phrase 'rendered artifact' implies the tool should be used after rendering and before delivery, but no alternatives or exclusions are named. An agent can infer the timing from context rather than from explicit guidance.

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