list_datastores

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

No annotations are provided, so the description should carry the full behavioral burden. It states the purpose but gives no indication of side effects (likely read-only), performance, pagination, or error conditions. Since it's a listing operation, it's probably safe, but the description does not explicitly reassure the agent about safety or other behaviors.

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 sentence that is clear and to the point. It efficiently states the purpose and the context (vCenter, provisioning) without filler. It could potentially be expanded with usage guidance, but given the schema's coverage, it is appropriately concise.

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 tool's simplicity (list operation, two parameters fully documented in schema, output schema exists), the description is sufficient for basic invocation. However, it does not mention return value structure (though output schema exists) or any specific behavior like whether it lists only datastores accessible to the given host/cluster. This is a minor gap, but the core functionality is clear enough for most use cases.

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?

The schema descriptions are already comprehensive (100% coverage): both parameters have clear descriptions including how to obtain them via sibling tools. The tool description adds little beyond the schema, so the baseline of 3 applies. No additional meaning is provided beyond what's in the schema.

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 ('List') and resource ('datastores') and adds the context of vCenter and its use for desktop pool or farm provisioning. It does not explicitly distinguish from the sibling 'list_datastore_clusters', but the resource is clear enough to infer the difference.

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 the tool is used when datastores are needed for provisioning, and the parameter descriptions guide the user to use sibling tools (list_virtual_centers and list_hosts_or_clusters) to obtain required IDs. However, it does not explicitly state when to use this over list_datastore_clusters or other alternatives, leaving some inference to the agent.

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