scan_junk

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

With no annotations, the description must cover behavior. It says 'Scan' which implies a read-only operation, but it does not explicitly state that it does not modify anything, nor does it disclose what it returns (e.g., a list of caches, sizes). No permissions or side effects are mentioned, leaving significant behavioral ambiguity.

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 sentence, which is concise, but it is under-specified rather than efficiently detailed. It front-loads the verb 'Scan' but provides no useful structure or breakdown of capabilities. It is more an under-specification than a model of conciseness.

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 no annotations, no output schema, and a parameter with zero schema descriptions, the description is grossly incomplete. An agent cannot determine what the tool returns, how to use the categories parameter, or how this tool relates to cleaning and disk usage. Essential information is entirely absent.

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 only parameter, 'categories', is an array with enum values, but the schema lacks any descriptions (coverage 0%). The description does not mention the parameter at all, so the agent has no idea what values to pass or what they control. Description fails to compensate for the schema gap.

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 states the verb 'Scan' and the resource 'macOS developer/system caches and reclaimable space', which conveys a broad intent but is vague. It does not distinguish from sibling tools like clean_junk or get_disk_usage, and the phrase 'reclaimable space' is not a concrete resource. It is not a tautology, but it lacks specificity.

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?

No guidance is provided on when to use this tool versus alternatives such as clean_junk or get_disk_usage. There is no mention of prerequisites, typical use cases, or exclusions. The agent is left to infer the tool's role in the workflow.

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