list_vaults

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

The readOnlyHint annotation already indicates a read-only operation. The description adds useful context by specifying that the vaults are 'explicitly registered', clarifying the scope of the list. It does not contradict the annotations and provides enough behavioral transparency for a simple list operation.

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 a single, front-loaded sentence with no wasted words. It conveys the tool's purpose and scope efficiently.

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 zero-parameter, read-only list tool with no output schema, the description adequately covers what the tool does. It could mention that it returns the list of vaults, but the verb 'List' and the context make this obvious enough. The description is complete for its simplicity.

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?

There are zero parameters, so the schema is fully covered at 100%. The description naturally has no parameter details to add. Per guidelines, a baseline of 4 is appropriate when there are no parameters.

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 the tool's function: 'List the explicitly registered Obsidian vaults available for selection.' It uses a specific verb ('List') and resource ('registered Obsidian vaults'), and differentiates from sibling tools like register_vault or get_vault by focusing on enumeration of registered vaults.

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 implies usage ('available for selection') but does not explicitly state when to use this tool versus alternatives such as get_vault or register_vault. No exclusions or alternative recommendations are provided, leaving the guidance implicit.

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