mf_get_billing

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool retrieves information, implying it's a read-only operation, but doesn't clarify aspects like authentication requirements, error handling (e.g., invalid billing_id), rate limits, or what '詳細情報' (detailed information) includes. For a tool with zero annotation coverage, this leaves significant gaps in understanding its behavior.

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 a single, efficient sentence in Japanese: '請求書の詳細情報を取得します'. It's front-loaded with the core purpose, has zero wasted words, and is appropriately sized for a simple retrieval tool. Every part of the sentence directly contributes to understanding the tool's function.

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 the complexity (a retrieval tool with no output schema and no annotations), the description is incomplete. It doesn't explain what '詳細情報' includes (e.g., fields returned), error conditions, or authentication needs. Without annotations or an output schema, the description should provide more context to help the agent use the tool effectively, but it falls short.

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 has 100% description coverage, with the billing_id parameter documented as '請求書ID' (invoice ID). The description doesn't add any parameter-specific details beyond what the schema provides, such as format examples or constraints. Given the high schema coverage, a baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't need to heavily supplement the schema.

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 states the tool's purpose: '請求書の詳細情報を取得します' (retrieves detailed information of an invoice). It specifies the verb '取得します' (retrieves) and the resource '請求書の詳細情報' (invoice details). However, it doesn't explicitly differentiate from sibling tools like mf_list_billings (which lists multiple invoices) or mf_get_quote (which retrieves quote details), though the resource specificity helps somewhat.

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?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing a billing_id), contrast with mf_list_billings for listing multiple invoices, or specify use cases like viewing specific invoice details after listing. Without such context, the agent must infer usage from the tool name and schema alone.

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