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

Annotations provide readOnlyHint=true, covering safety. The description adds valuable behavioral context: costs are compute-only estimates from cloud list prices, which is crucial for interpreting results correctly. It does not describe return format or pagination, but this is above the baseline for a read-only tool.

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 tightly written sentences. The first defines the action and scope; the second adds a critical caveat about cost estimation. Every sentence earns its place and the purpose is front-loaded.

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 simple read-only cost getter with full parameter schema coverage and no output schema, the description covers purpose, scope, and the nature of the cost data. It could optionally hint at the return format (e.g., a monetary estimate), but overall it is complete enough for correct invocation.

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 both parameters (stack_name and cluster_id) are fully documented in the schema. The description reinforces the target (specific stack, current cluster) but adds no syntax or format details beyond the schema, warranting the baseline score.

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 ('Get the estimated cloud infrastructure cost attributed to a specific stack') and clarifies scope by noting derivation from the stack's namespaces. This distinguishes it from cluster-level or namespace-level cost tools without naming them.

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?

No explicit when-to-use or when-not-to-use guidance. It describes the tool's function but does not compare to alternatives like get_cluster_cost or get_namespace_cost_history, leaving the agent to infer appropriate use cases.

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