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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds valuable behavioral context beyond annotations by disclosing the cost model: free within a daily allowance, then $0.002 USDC per call via x402. It does not describe error handling for invalid IDs, but the pricing disclosure is a meaningful addition.

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 with zero waste: the first states what is returned and the accepted identifier formats, the second discloses the cost model. The most important information is front-loaded and every sentence earns its place.

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?

For a simple single-resource lookup tool with full schema coverage and an output schema, the description supplies the essential identifier formats and the pricing model. It omits error behavior for unknown IDs and does not mention the output structure, but the latter is covered by the output schema. The description is nearly complete for the tool's complexity.

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 single id parameter is already documented as 'OpenAlex id or doi:…'. The description adds concrete prefix examples ('W…' and 'doi:10.…'), but this is marginal value beyond the schema. The baseline of 3 is appropriate when the schema already does the heavy lifting.

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 states it returns a single scholarly work identified by OpenAlex ID or DOI, which distinguishes it from the sibling scholarly__works-search tool. However, it does not use a direct verb like 'retrieve' and does not explicitly name the alternative search tool, so it falls just short of full sibling differentiation.

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 description implies usage by specifying the required identifier formats, but it never states when to use this lookup versus scholarly__works-search or crossref__doi. There is no explicit guidance on when this tool is preferred over alternatives, leaving the agent to infer the context.

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