Check a draft against the library

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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the description only needs to add matching semantics — and it does: spelling variants ('603 U.S. 369 = 603 US 369'), optional pincite or year, duplicate citations reported twice, results in order. It does not resolve the tension in its final clause, which implies the tool also surfaces citations the library lacks, even though the opening sentence says it reports matches to library authorities only.

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?

Two tightly packed sentences, front-loaded with the core behavior and matching rules, with no filler. The trailing clause about finding citations the library does not have is the only part that costs clarity rather than adding it.

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?

There is no output schema, but the description covers the essentials an agent needs — ordering, duplicate handling, fuzzy matching on citation format, and pagination via the schema. It stops short of saying what a single reported mention contains (position in text, matched case reference), and leaves the whether-unmatched-citations-are-returned question open.

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%, with text, limit, and offset all documented in the schema, including that offset should use the previous call's nextOffset. The description adds nothing about these parameters, so the baseline of 3 applies.

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 precise verb and resource: scan draft text and report every place it cites an authority already in the library, returned in order. That framing immediately separates it from the sibling search_* / list_* tools, which retrieve library items rather than resolving citations inside a draft.

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?

Gives an explicit use case: check a draft against the research behind it. It does not name an alternative tool or state when not to use it, so an agent still has to infer that this is not a general citation parser for text unrelated to the library.

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