空间占用分析

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

No annotations exist, so the description carries the full disclosure burden. It does describe what the analysis returns, but it says nothing about read-only safety, permissions, cost, scan time, or whether the scan recurses. For a recursive filesystem scan with no annotations, those omissions matter.

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?

Two tight sentences, with the core capability front-loaded and the use-case cue trailing. The parenthetical file-type list earns its place by previewing the output categories, and nothing is redundant.

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?

With no output schema, the description compensates by enumerating the returned sections, and all three parameters are fully documented in the schema. The only gap is operational behavior: depth of recursion and performance limits are not stated.

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 coverage is 100%, so path, top, and max_entries are already documented in the schema. The description adds context that the 'top' parameter drives the 'top subdirectories' section and names the file-type buckets, but it adds no format guidance or defaults beyond the schema, so baseline 3 applies.

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 uses a specific verb-plus-resource framing ('分析一个目录的空间都去哪了') and enumerates the three result components: top subdirectories, distribution by file type, and largest files. That is enough for an agent to distinguish it from get_video_info or read_exif. It does not explicitly contrast with the overlapping sibling probe_dir, which keeps it from 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?

It supplies a concrete triggering scenario ('手机空间不够了帮我看看'), so an agent knows the situation that should select this tool. It offers no explicit when-not conditions or named alternatives such as probe_dir or find_duplicates, so it falls short of full routing guidance.

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