librarian_gap

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

No annotations, so the description carries the full behavioral burden and does substantial work: it says the report goes on a gap ledger, that every review re-hunts open gaps, and that still-unanswerable gaps escalate to the operator. That explains the downstream consequence of calling, which an agent otherwise couldn't infer. It stops short of saying whether duplicate gaps are merged or how quickly a gap is acted on.

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 core purpose and the librarian_tell escape hatch are front-loaded in the first sentence, and the ledger/escalation context follows usefully. The trailing `caller` note is appended after the behavioral explanation where it reads as an afterthought, and a stray line break splits the first sentence.

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?

An output schema exists, so return values needn't be explained, and the lifecycle of a gap is well covered. What's missing is guidance on the two required parameters, which is the main thing an agent still needs in order to file a usable report.

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 0%, so the description must compensate, but it only addresses the optional `caller` parameter ('optional caller label; leave it empty'). The two required parameters, `subject` and `missing`, get no explanation of format, granularity, or what distinguishes a good report from a bad one.

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?

States a specific verb+resource ('REPORT a gap') and defines the gap as something the librarian was missing, with an explicit contrast to the sibling librarian_tell for when you do have the answer. An agent can distinguish this from librarian_tell and the other librarian_* tools without inspecting schemas.

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?

Explicitly names the alternative (librarian_tell) and the condition that selects it ('you don't have the answer yourself'). This is a clear when-to-use / when-to-use-something-else rule.

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