mf_list_items

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions filtering capability but doesn't describe pagination behavior (implied by page/per_page parameters), rate limits, authentication requirements, error conditions, or what the return format looks like. For a list retrieval tool with zero annotation coverage, this leaves significant behavioral aspects undocumented.

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 appropriately concise with two clear sentences that communicate the core functionality. The first sentence states the primary purpose, and the second adds important filtering capability. There's no wasted verbiage or redundant information.

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 list retrieval tool with 3 parameters and no output schema, the description is insufficiently complete. It doesn't explain what an 'item' represents in this context, what fields are returned, how pagination works, or any authentication requirements. The lack of output schema means the description should ideally provide some indication of return format, but it doesn't.

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 the schema already documents all three parameters (page, per_page, q) with their types and descriptions. The description adds minimal value beyond the schema by mentioning keyword filtering ('検索キーワードで絞り込み可能です'), which aligns with the 'q' parameter. However, it doesn't provide additional context about parameter interactions or constraints beyond what's in 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 verb ('取得します' - get/retrieve) and resource ('品目一覧' - item list), making the purpose immediately understandable. It also mentions filtering capability ('検索キーワードで絞り込み可能です'), which adds specificity. However, it doesn't explicitly differentiate from sibling tools like mf_get_item, which appears to retrieve a single item rather than a 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?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when to use mf_list_items versus mf_get_item (for single item retrieval) or other list tools like mf_list_billings, mf_list_partners, or mf_list_quotes. There's no context about prerequisites, typical use cases, or limitations.

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