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

The description is straightforward and consistent with the readOnly annotation, but it does not disclose additional behavior such as return format, error cases, or how the earliest/latest values are determined. The annotation already covers the read-only nature.

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 a single concise sentence that directly states the function and its purpose, with no unnecessary words or repetition.

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 simple version-range lookup, the description provides sufficient context, especially by referencing get_app_version. It does not need to explain the return value in detail since the tool's purpose is clear and the domain is narrow.

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?

The input schema fully documents both parameters (slug and app_id) with descriptive text, and the description reinforces the by-slug-or-id usage. There is no additional parameter nuance beyond the schema.

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 clearly states the tool gets the earliest and latest version numbers of an app, and distinguishes it from get_app_version by framing the result as the range to fetch individual versions.

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?

It indicates the intended use case ('to know the range you can fetch with get_app_version') and implicitly guides when to use it relative to get_app_version, though it does not explicitly contrast with other sibling tools.

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