list_hosts_or_clusters

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds useful dependency context (the ID feeds other calls), but discloses no permission requirements, rate limits, or scoping behavior beyond that. With annotations carrying the safety signal, this is adequate but not rich.

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, front-loaded with the core purpose and followed by a single high-value dependency note. No filler, and the most important clause (what it lists) comes first.

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 not be described, and annotations cover safety. The description covers purpose and downstream usage, leaving only minor gaps (e.g., relationship to adjacent hierarchy levels) unaddressed.

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% and both parameters (vcenter_id, datacenter_id) are documented in the schema with sourcing hints. The description adds no parameter-level meaning beyond what the schema provides, so the baseline of 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+resource ('List hosts and clusters') and scopes it precisely ('in a vCenter datacenter'). This clearly separates it from sibling listers such as list_datacenters and list_virtual_centers, which operate at different levels of the hierarchy.

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 second sentence supplies real usage context by naming the downstream consumers of the returned host_or_cluster_id (list_datastores, list_resource_pools, list_network_labels, create_desktop_pool, create_rdsh_farm), telling the agent why to call this first. It stops short of explicit when-not guidance, but there is no direct alternative for this resource.

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