make_folder

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

Annotations declare the mutation profile (readOnly=false, destructive=false, idempotent=false), and the description adds meaningful context beyond them: the parent-existence precondition and that the change is logged and undoable. It stops short of stating behavior on duplicate paths or required permissions.

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 sentences, zero filler, with the core action front-loaded and the precondition and reversibility following in priority order.

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?

An output schema exists, so return values need no explanation. The description covers creation, the key precondition, and reversibility; only edge cases (existing folder, permission requirements) are left unstated, which is minor for this 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 100%, so all three parameters (vault, path, purpose) are already documented, including the parent-existence constraint. The description adds no syntax, format, or naming detail beyond the schema, so the baseline 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 ('Create a new, empty folder') plus the scope ('in an open vault'), which separates it from write_file/append_file siblings. It does not explicitly name an alternative tool, but the operation 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?

The precondition 'Its parent folder must already exist' is genuine usage guidance, telling the agent when the call will fail. However, there is no when-to-use/when-not guidance relative to siblings (e.g., write_file creating intermediate paths) and no mention of what happens if the folder already exists.

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