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

Annotations already declare readOnlyHint=true and destructiveHint=false, yet the description adds genuinely new behavior: an empty library is an answer rather than an error, "held" claims are unusable, and every number must travel with its self-critical caveat. These are operational facts the annotations do not cover.

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 content is front-loaded with the resource definition and the imperative to read before citing, then layers in the held/caveat rules. It runs long for a zero-arg read tool and repeats the caveat idea ("the caveat is what makes the number safe to say"), but each sentence carries usable meaning.

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, so the description must describe the return shape, and it does: each claim carries a sentence, a number with unit, relevance keywords, and a caveat. Combined with the safety annotations and held/empty edge cases, nothing needed to call it correctly is missing.

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 per the rubric the baseline is 4. There is nothing parameter-side for the description to compensate for, and it correctly omits any argument discussion.

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 establishes the resource ("the claim library") and elaborates its contents in detail: a one-sentence claim, a number with unit, keywords, and a caveat. It does not use an explicit verb or name the sibling record_claim as the write counterpart, but the read purpose is unmistakable.

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?

It gives an explicit when-to-use directive ("READ THIS BEFORE CITING ANY NUMBER about this product") and a hard when-not-use rule ("A claim marked held is NOT for use"). The caveat requirement ("never quote a claim without its caveat") further constrains correct invocation, leaving little to inference.

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