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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the bar for transparency is lower. The description adds valuable behavioral context: it is Spotlight-free, paths are restricted to an allowlist, and access denied errors name the allowed folders. This goes beyond the annotations without contradicting them.

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 two sentences, front-loaded with the main purpose, and every clause adds useful information (Spotlight-free, allowlist, error behavior). No redundant or filler content.

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?

Given the simple nature of the tool, the rich annotations, and the presence of an output schema, the description is largely complete. However, the sibling list includes file_list and finder_search, and the description does not clarify how finder_list differs from these similar tools, leaving some potential for selection ambiguity.

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 description coverage is 100% and both parameters have clear descriptions with defaults ('path' default ~, 'limit' default 100). The tool description adds no additional parameter semantics beyond the schema, so the baseline score of 3 is appropriate.

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 lists files and folders in a directory with the parenthetical 'Spotlight-free' adding a distinguishing characteristic. It does not explicitly differentiate from the sibling tool file_list, which likely performs a similar filesystem listing, so it falls short of a 5.

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 provides clear operational context: the path must be inside the allowed folder and paths outside it yield an actionable access denied error. However, it does not explicitly state when to use this tool over alternatives like file_list or finder_search, nor when not to use it.

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