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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds real value beyond that: results are limited to items present in the NobleBlocks index (partial-coverage caveat) and are ordered most-cited first, both of which affect interpretation of output.

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 well-formed sentence with the subject, scope qualifier and sort order front-loaded and zero 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?

With an output schema, full parameter documentation and rich annotations, the description only needs to convey direction, index coverage and ordering — all of which it does. Minor gaps (e.g., behavior when the identifier resolves to a paper with no indexed references) are not material.

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% and every parameter (identifier, limit, offset) is documented in the schema, so the description adds nothing parameter-specific. Baseline 3 applies when the schema does all the work.

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 resource and direction ('papers this paper cites (its reference list)'), which inherently distinguishes it from the reverse-direction sibling get_citing_papers. It also adds an important scope qualifier ('in the NobleBlocks index'), but it never names the sibling it is being contrasted with.

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 implicit use case is clear (retrieve a paper's reference list given an identifier), and the directional wording steers away from get_citing_papers. However, there is no explicit when-to-use/when-not guidance or named alternative.

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