compare_scans

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

With no annotations, the description carries full burden. It discloses that the tool compares two scans and returns a comparison report with capacity changes and top growth/shrink paths. It does not mention destructive or side effects, but the nature of comparison implies read-only. It provides sufficient behavioral context.

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 well-structured with a summary line, usage guidance, parameter details, and return description. It is concise yet complete, with no unnecessary fluff.

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 tool has 3 parameters and an output schema (not shown but noted), the description covers all necessary context: purpose, usage, parameters, and return value. It is complete for an agent to understand when and how to use it.

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 0%, meaning the JSON schema provides no parameter descriptions. The description fully compensates by explaining each parameter (scan_id_before, scan_id_after, limit, ctx) in the Args section, including defaults and types.

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 compares two scans of the same drive to identify changes. It uses specific verbs like compare, measure, track, and identify, and distinguishes itself from sibling tools (e.g., list_scans, cleanup_scans) by focusing on diff rather than listing or cleanup.

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 explicit use cases (measure cleanup results, track growth, identify directories with most change) and implies when to use it. However, it lacks explicit when-not-to-use advice or direct alternatives, which would raise it to a 5.

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