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

Annotations already declare readOnlyHint=true, so the closing 'Read-only' is largely redundant, but the description adds real behavioral context the annotations do not: the set of supported providers, the eligibility restriction for imported/managed-Kubernetes clusters, and the fact that control-plane output includes whether it can be changed right now and why not. It does not cover pagination or response shape, but no output schema exists and the field list is already enumerated.

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?

Purpose is front-loaded in the first clause and every sentence carries usable information, including the routing sentence and the eligibility caveat. The middle sentence is a long run-on enumeration of return fields, but each listed item is genuinely useful given there is no output schema.

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?

With no output schema, the description compensates by enumerating the returned fields (instance type, node count, scaling bounds, labels, taints, autoscaling, control-plane counts and changeability). Combined with the eligibility restriction and the sequencing guidance, an agent has everything needed to call it correctly.

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 cluster_id and cluster_name are already fully documented, including the 'optional when a cluster is selected' semantics. The description adds no parameter-level detail beyond that, 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 (list) and a precisely scoped resource (day-2 topology of Ankra-provisioned self-managed clusters), then enumerates exactly what comes back: worker node groups with their attributes, control plane details, and the legacy worker count. It is clearly distinguishable from sibling readers like list_cluster_nodes or get_nodes because it names node groups, control plane, and scaling bounds.

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?

Explicitly names the five mutating tools it should precede (scale_workers, add_node_group, update_node_group, delete_node_group, change_control_plane), giving an unambiguous when-to-use rule. It also states the negative case: 'Not available for imported or managed-Kubernetes clusters.'

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