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

Annotations already declare a non-readonly, non-idempotent, non-destructive mutation. The description adds genuinely useful context beyond that: provisioning happens asynchronously at the cloud provider and the cluster must be fully provisioned first.

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?

Four dense but well-ordered sentences that front-load the action, then prerequisites, then optional blocks. No filler, though the count/autoscaling restatement slightly overlaps the 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?

Given 9 parameters with nested objects and no output schema, the description covers the critical gaps: prerequisites, where the size comes from, and that node provisioning is asynchronous. It could mention how to check pool status afterward, but the essentials are present.

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 coverage is 100%, so every parameter is already documented in the schema, including count defaulting to 1 and the autoscaling constraints. The description largely restates those defaults, adding little new syntax or format detail.

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 (add a node pool to a managed Kubernetes cluster) and enumerates the supported providers, which lets an agent distinguish it from sibling mutations like update_managed_node_pool or add_node_group.

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 states the required inputs, where the size slug comes from (list_managed_k8s_options with the cluster target), and the precondition that the cluster must have finished provisioning. It stops short of naming when to prefer add_node_group or update_managed_node_pool instead.

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