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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered. The description adds useful behavioral constraints beyond annotations: it lists only one folder at a time, only shows files within the web root, and excludes hidden files. It does not discuss errors or pagination, but those are minor gaps for this read-only listing tool.

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?

The description is compact and front-loaded: it states what is returned, how to navigate, and why to use it before related tools. Every sentence contributes useful selection or invocation context, with only the final 'Read-only' being mildly redundant with annotations.

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 two-parameter read-only listing tool with no output schema, the description is complete enough: it explains the return fields, root/path navigation, scope limits, and relationship to read/write file tools. An agent has what it needs to call and interpret this tool 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?

Schema description coverage is 100%, so both parameters are already documented in the schema. The description reinforces root behavior and one-folder-at-a-time navigation but adds little parameter syntax or semantics beyond what the schema provides; baseline 3 is appropriate.

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: lists one folder of a shared hosting site's web root, and even names the returned fields (name, type, size). It is clearly distinguishable from related file tools by noting it is for listing folders before using read_site_file or write_site_files.

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 explicit operational guidance: start at the root with no path, descend one folder at a time, and use this before read_site_file / write_site_files so paths are real. It also sets clear boundaries by saying hidden files and anything outside the web root are never shown.

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