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

Annotations already declare readOnlyHint=true, and the trailing 'Read-only' largely restates that. However, the description adds real behavioral context beyond the annotation: the closed set of phase values, the conditional nature of the URL ('when one is published'), and the fact that size/price are historical values of record. It doesn't discuss latency or cache/refresh behavior, keeping it at 4.

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?

Dense and front-loaded: the returned-field enumeration comes first, then the two use cases, then the safety tag. Every sentence earns its place except the redundant 'Read-only' trailer, which duplicates the annotation.

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?

There is no output schema, so the description carries the return-value burden and does so thoroughly by naming the phase enum, expiry, URL, size and price. For a one-optional-parameter read tool, an agent has everything needed to call and interpret it.

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 the single cluster_id parameter already documents its UUID format and its optionality when a cluster is selected in conversation. The description adds nothing about the parameter, 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?

The description states a specific verb ('Report') and resource ('a playground environment's provisioning phase') and enumerates the exact fields returned: phase, expiry, starter-app URL, ordered size and price of record. That level of detail lets an agent distinguish this from generic status readers like get_cluster_status without opening the schema.

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?

It gives explicit usage contexts: 'poll a create_playground order until the phase reaches ready' and 'answer what size or price an existing playground is', naming the sibling create_playground as the counterpart. It stops short of stating when not to use it (e.g., versus resize_playground or destroy_playground), so it falls just short of a 5.

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