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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds genuine value beyond that: it explains that the URL field holds the NobleID ARK when confirmed, else the DOI, and that unreliable DOIs are omitted rather than guessed — a real data-quality behavior an agent would otherwise not expect.

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 short sentences: the core action and formats come first, then the fallback caveat. No filler, nothing repeated for its own sake.

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 present, return formatting needn't be described, and both parameters are fully documented in the schema. The description covers the format choice and the identifier-resolution caveat, leaving only the relationship to the `cite` sibling unaddressed.

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 the format enum is documented in the schema, so the baseline is 3. The description restates the three formats and adds context about identifier resolution into the URL, but gives no per-parameter detail beyond what the schema already supplies.

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 states a specific verb and resource ("Format a citation for one paper") plus the three supported output formats, so an agent knows exactly what it produces. It does not differentiate itself from the sibling `cite` tool, which is the obvious ambiguity an agent would face here.

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?

Usage is implied only: it formats a citation for a single paper, so the agent can infer it should have a paper identifier in hand. There is no explicit when-to-use/when-not-to-use guidance and no mention of the very similar `cite` sibling, leaving the routing decision to inference.

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