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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the behavioral context that the tool selects an existing folder rather than creating one, which aligns with the annotations. It does not add deeper behavioral details like ranking behavior or no-match handling, but the annotations lower the bar for this dimension.

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 sentences with no filler: the first states the tool's purpose and the second gives the key usage directive. The important scoping phrase 'existing folder' is front-loaded, and every clause earns its place.

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?

Given the rich annotations, complete input schema, and presence of an output schema, the description is mostly self-sufficient. It tells the agent when to call the tool and why. A minor gap is that it does not describe what happens when no suitable folder is found, but this could be covered by the output schema and is not essential for the caller's decision.

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 the parameters are already well documented in the schema. The description loosely maps to the 'description' parameter by saying 'based on a description of its content,' but it adds little beyond the schema. The vault_id parameter is richly documented in the schema itself, so no compensation is needed.

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 states a specific verb and resource: 'Find the best existing folder for a new note based on a description of its content.' It clearly distinguishes this tool from sibling folder tools like list_folders (which lists all folders) and create_folder (which creates a new one), so an agent can tell them apart.

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 description explicitly says when to call it: 'Call before create_note when the right folder is unclear.' This gives clear contextual guidance and a direct workflow connection to create_note. It does not explicitly name alternatives or exclusions, but the condition 'when the right folder is unclear' is a sufficient usage signal.

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