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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the useful constraint that only "visible" folders can be queried, hinting at access scoping, but says nothing about permission failures or what happens for inaccessible hashes. An output schema exists, so return format needs no explanation.

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?

One sentence with no waste, and the core purpose is front-loaded. It is arguably too terse given the undocumented parameter, but it is well-structured and free of filler.

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?

This is a simple single-parameter read tool with an output schema, so much of the burden is off the description. Still, the undefined folder_hash and the lack of routing guidance relative to list_folder and get_file_info leave real gaps for an agent choosing and calling the 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% and the single parameter folder_hash has no documentation anywhere. The description never explains what a folder hash is, its format, or how to obtain one (e.g., from get_root_folder or list_folder), so it fails to compensate for the coverage gap.

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 ("Return metadata") and resource ("one visible Files.fm folder"), which distinguishes it from list_folder (contents) and get_file_info (files). It does not explicitly name those siblings, so the differentiation is only implied.

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?

Usage is only implied: the agent must infer that this tool fetches a single folder's metadata rather than its listing or its files. There is no explicit when-to-use or when-to-prefer-list_folder guidance.

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