ftp_dir_size

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

No annotations are provided, and the description only states the core operation. It does not disclose potential cost of recursive scans, behavior on missing paths, or whether an existing connection is required, leaving important behavioral context undocumented.

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 with no filler, directly and efficiently stating the tool's function. It is front-loaded and every word earns its place.

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 and no annotations, the description omits return format (e.g., bytes vs human-readable) and prerequisites (e.g., requires an existing connection). While the core purpose is clear, operational details are left ambiguous, making it less complete for agent invocation.

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 input schema already provides clear descriptions for both parameters (path as remote directory, connection as connection name) with 100% coverage. The description adds the recursive behavior but no new parameter-level insights, so the baseline of 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 clearly states the tool calculates the total size of a remote directory recursively, providing a specific verb and resource. It distinguishes from siblings like ftp_stat by focusing on recursive directory size, though it does not explicitly name alternatives.

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 ftp_stat or ftp_tree. The recursive scope implies whole-directory sizing, but there is no explicit when/when-not or alternative recommendation.

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