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

Annotations already mark the operation as non-read-only, non-destructive, and not idempotent; the description adds the useful behavioral detail that the document itself is not opened, just surfaced in the file manager. However, it does not describe side effects such as launching a file manager UI or what happens for invalid paths.

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 sentence that is front-loaded with the trigger condition and states both the action and its limiting behavior. There is no filler or redundant restating of the schema.

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 two-parameter tool with a present output schema and fully documented parameters, the description covers the key intent and the important 'does not open the document' distinction. It could mention error cases or permission requirements, but the core invocation context is 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 documentation covers 100% of parameters, so the schema carries the semantic weight. The description reinforces that the path is a permitted local file or directory but does not add meaningful format or behavior details 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?

Description uses a specific verb ('reveal') with a specific resource ('permitted local file or directory') and names the target context (Finder/Explorer/file manager). The phrase 'without opening the document itself' clearly differentiates this from the sibling open_path.

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 description explicitly states when to use the tool: when the user needs to reveal a file or directory in a file manager without opening it. It does not name alternatives or give exclusions, so it is clear context without full when-not-to-use guidance.

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