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

Annotations already declare read-only, idempotent, non-destructive behavior; the description goes beyond them by disclosing the $0.003 cost, the returned payment instructions, and that no provider account is required. These are exactly the operational traits an agent needs before invoking the tool. No contradiction with annotations.

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?

Four short sentences, front-loaded with the core purpose and followed by essential operational facts: exclusions, cost, and authentication context. Every sentence earns its place; the cost disclosure is material information for tool selection, not 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?

For a single-parameter tool with rich annotations and no output schema, the description enumerates the returned artifact categories and their exclusions while also covering cost and account requirements. Nothing an agent needs in order 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?

Schema coverage is 100%: the sole parameter is documented with its optional https://doi.org/ prefix. The description merely echoes that the parameter is a DOI without adding new format or usage nuance. With complete schema coverage, the baseline of 3 is appropriate.

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 names a specific action ('Resolve a DOI') and resource, then lists the exact delivered outputs: normalized metadata, citation text, identifiers, and source links. The explicit exclusion of abstracts and full text sharpens the boundary against document-retrieval tools. Among 27 sibling tools, the DOI/citation scope is unambiguous.

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 intended use case—having a DOI and needing citation-level metadata—is clearly implied by the first sentence, and the abstract/full-text exclusion signals what this tool is not for. However, no alternative tool is named and no explicit when-not condition is stated, so an agent must infer routing from DOI-specific vocabulary rather than being directed.

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