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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds meaningful behavior beyond that: results are non-recursive direct children only, the exact return shape {key, name, rel_path, is_dir, size, modified}, and the dependency that key must be harvested from a previous call. Pagination, size limits, and error behavior remain undisclosed.

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?

Front-loaded with the core purpose, then parameter guidance, then return shape and downstream use — a logical ordering with no filler. The semicolon-and-dash compression makes it dense but still parseable; a little breathing room would not hurt.

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 correctly spells out the returned record fields, and it flags the non-recursive scope and the key-chaining requirement that would otherwise cause failed calls. Missing connection_id semantics and any notion of result limits keeps it short of complete for a 3-parameter listing tool.

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%, so the description carries the burden, and it does well for two of three parameters: path is a relative path with '' meaning root, and key is the provider-side folder id with its provenance explained. connection_id, the only required parameter, is never mentioned, leaving a real gap given zero schema documentation.

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?

States a specific verb+resource: listing files and folders that are direct children of a cloud directory, and explicitly rules out recursion with '(прямые дети)'. An agent can distinguish it from list_clouds, list_transfers, and read_text_file without opening any schema.

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?

Gives concrete operating context: empty path means root, key must come from a prior list_files result on key-based clouds like Google Drive, and the returned entries feed create_transfer. It lacks an explicit when-not (e.g., what to call for nested trees or for reading file content), so it stops short of full alternative routing.

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