ncloud_get_demand_cost_list

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

Annotations already declare readOnlyHint=true, so the safety profile is known. The description adds the 'max 3 months' range constraint and clarifies that return values include discounts, VAT, and payment status. However, it does not disclose pagination behavior or the effect of partner/organization flags, which are relevant for a tool with these parameters.

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?

The description is two sentences with no irrelevant detail. It front-loads the core purpose and adds only essential return-value context. Every clause earns its place.

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 read-only list tool with 100% schema coverage and a readOnlyHint annotation, the description provides adequate context: it states what is returned and the range limit. It does not explain partner/organization semantics, but those are documented in the schema. The main gap is the lack of differentiation from close sibling tools, which is more of a usage-guideline issue.

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?

The input schema provides descriptions for all 7 parameters, achieving 100% coverage. The tool description adds no extra parameter information beyond what the schema already states (e.g., format of startMonth/endMonth, pageSize limits). Baseline 3 is appropriate since schema does the heavy lifting.

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 clearly identifies a read operation for monthly billing cost data with a specific verb ('Get') and resource ('monthly billing cost list'). It adds useful context about what is included (discounts, VAT, payment status). However, it does not differentiate from similarly named sibling tools like ncloud_get_product_demand_cost_list or ncloud_get_contract_demand_cost_list.

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 guidance is provided on when to use this tool versus the many related billing/cost tools (e.g., ncloud_get_product_demand_cost_list, ncloud_get_contract_demand_cost_list). The description does not mention alternatives, prerequisites, or context such as whether this is the default/all-services cost view.

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