get_balance

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

With no annotations, the description carries the full burden. It usefully discloses that the call consumes 0 credits (a real behavioral trait) and that the operation is a read, but says nothing about authentication, rate limits, or whether the expiry list is paginated or truncated.

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?

A single front-loaded sentence naming the returned data, with the cost note tucked into a parenthetical. Every element earns its place and nothing is redundant.

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 zero-parameter read with no output schema, the description adequately conveys both the return content (balance plus lot expiration list) and the cost. It is only slightly incomplete in not hinting at response shape or freshness of the balance data.

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 tool takes zero parameters, so there is nothing for the description to disambiguate. Baseline 4 applies; no compensation is needed.

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 states a specific verb (取得) and two concrete resources (現在のクレジット残高 and ロットの有効期限一覧), so an agent knows exactly what it returns. The sibling tools are all company-search oriented, so there is no ambiguity to disambiguate.

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?

Usage is only implied — an agent infers it should call this when it needs credit/expiry information, but there is no explicit when-to-use, prerequisite, or alternative stated. The '(消費クレジット: 0)' note is a useful cost hint but does not constitute routing guidance.

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