ndl_get_record

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral detail beyond annotations by explaining that the envelope omits 'searched_for' because no search term is chosen, which gives the agent insight into the response format.

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?

Three short sentences convey the purpose and the key operational distinction. The description is front-loaded with the primary action, and every sentence adds relevant information with no filler.

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 single-record fetch tool, the description is complete: it covers the identifier requirement, the fetch-vs-search distinction, and a response envelope nuance. The output schema and annotations handle return format and safety, so nothing essential is missing for the agent to invoke this tool correctly.

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?

With schema description coverage reported at 0%, the description partially compensates by naming both accepted identifier types: NDL bibliographic ID and 全国書誌番号. It also adds the critical constraint that exactly one identifier is required, which is not enforced by the schema (both params are individually optional). However, it does not elaborate on identifier format or which identifier should be preferred when both are known.

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 uses a specific verb and resource: 'Retrieve a single record by NDL bibliographic ID or 全国書誌番号 (JP number).' It further distinguishes itself from the search sibling tools by explicitly stating 'A fetch, not a search,' so an agent can clearly tell it apart.

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 gives clear context: this tool is for fetching by a known identifier, not for searching. It also provides a key usage requirement, 'Exactly one identifier is required,' which helps the agent avoid invalid calls. It does not explicitly name alternative tools, but since all siblings are search tools, the contrast is sufficient.

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