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

Goes well beyond the annotations (readOnlyHint=false, idempotentHint=false, destructiveHint=false): it discloses pro-rata monthly billing from readiness, the trial's one-per-organisation limit, the exact gating preconditions (billing permissions, paid plan, card on file, no overdue invoices, memory budget headroom), and that refusals name the missing piece. This is the behavioural context an agent needs before a non-idempotent create.

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?

One dense paragraph, but front-loaded with the core purpose followed by preconditions, billing, return value, and follow-up. Every sentence carries load, though the run-on length and mixed concerns make it slightly harder to scan than a structured version would be.

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?

For a one-param create tool with no output schema, it covers what is created, the default, the billing and permission gates, the return value (new cluster id), and the required follow-up call. Nothing an agent needs to invoke it correctly is missing.

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 already 100% for the single size parameter, so the baseline is 3. The description still adds value by naming the authoritative source (list_playground_plans) and the default semantics of omitting size (free trial), which the schema only partially conveys.

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 and resource ('Order a new Ankra Playground environment') and immediately characterizes it as a hosted Kubernetes namespace on a shared pool. This clearly distinguishes it from siblings like destroy_playground, resize_playground, list_playground_plans, and get_playground_status.

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 says where to get the size value (list_playground_plans), what omitting size does (orders the free trial, one per organisation, no billing), and what to do after the call (poll get_playground_status until phase is ready). It also flags the precondition checks and that list_playground_plans reports them up front.

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