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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false and openWorldHint=false, so the safety profile is covered. The description adds only that the result is an *empty* folder; it says nothing about permission requirements, name collisions, or what happens on duplicate creation. An output schema exists, so return-value description is not required.

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, zero waste, with the primary action and placement rule front-loaded and the id-source pointer as a trailing aid.

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 5-parameter creation tool with 20% schema coverage, the description covers placement and id sourcing but omits the optional metadata fields and any failure/conflict behavior. It is minimally sufficient to invoke correctly but not to invoke well.

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 coverage is only 20% — just `parentFolderId` is documented in the schema. The description restates that parameter's omit-for-top meaning and implies spaceId ('in a space'), but says nothing about `name`, `icon` or `description`, leaving three optional parameters with no semantic guidance anywhere.

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 ('Create an empty folder in a space') plus the placement scope ('at the top or inside `parentFolderId`'), which makes it easy to tell apart from folder.update, folder.delete and folder.restore. It does not explicitly name a sibling, but the verb/resource pair is unambiguous.

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 the two placement cases (top-level vs. nested under parentFolderId) and routes the agent to `workspace.structure` as the source of ids, which is real prerequisite guidance. It stops short of stating when to prefer this over other creation paths or any exclusions/preconditions.

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