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

Annotations already declare readOnlyHint=true, idempotentHint=true, so safety is covered. The description adds the error behavior for 'foreign refs' and the dependency on being used before creations_search, which goes beyond annotations. It does not describe return format, but for a simple read tool that's acceptable.

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?

Two short sentences, front-loaded with the action and key usage. Every word adds value; no fluff.

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 one param, no output schema, and strong annotations, the description covers the essential usage and error condition. It doesn't elaborate on return content, but the term 'metadata' gives a general expectation. The usage note adds important context for sequencing.

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 has only 'reference' with no description (0% coverage). The description says 'by reference' and implies it's a folder reference, giving meaning to the parameter. It could be more explicit about the format (ID vs path), but for a single straightforward param, this is adequate.

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 it fetches folder metadata by reference, which is a specific verb+resource action. It also differentiates from sibling tools like magnific_folders_list by focusing on a single reference, and mentions a prerequisite usage before creations_search.

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?

It explicitly says 'Use before creations_search (from=folder)', giving a concrete usage context. It also mentions that foreign refs error, which implies a constraint. However, it doesn't explicitly state alternatives or when not to use it, but the context is sufficient for most cases.

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