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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds value beyond that by disclosing the exact return fields (total_files, total_size_bytes, total_size_mb rounded to 2 decimals) in the absence of an output schema. It does not cover auth or workspace-resolution behavior, keeping it short of a 5.

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?

Three short, front-loaded blocks — purpose, when-to-use/alternative, return shape — each earning its place with no filler or repetition.

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?

For a single-parameter read-only tool with no output schema, the description supplies the missing pieces: trigger conditions, the sibling alternative, and the return field list. An agent has everything needed to select and call it correctly.

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?

There is a single parameter with 100% schema description coverage, and the schema already explains that workspace_id accepts a UUID or a user-spoken name and may be omitted when the token has a fixed workspace. The description adds no further parameter guidance, 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?

States a specific verb and resource ('Obtiene el uso de almacenamiento del workspace') and immediately scopes it to aggregate counts and consumed space rather than individual files. It explicitly names the sibling get_all_files for the file-level view, so an agent can distinguish it without opening schemas.

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 three concrete triggering situations (user asks about space used, whether more files can be uploaded, or auditing workspace files) and a routing rule away from itself ('Para ver los archivos individuales: usar get_all_files'). Nothing is left to inference.

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