Check Retraction

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint, and openWorldHint. The description adds substantial behavioral context beyond these: it sources from Crossref `updated-by`, resolves DOI/PMID/PMCID/arXiv/ADS inputs, explains ISBN handling, describes return format, confirms idempotency, and details rate limits and API key requirements. 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?

The description is appropriately sized for the tool's complexity. It front-loads the core purpose, then provides usage guidelines, behavioral details, and technical specifics. Every sentence adds value; there is no fluff or repetition. The structure is logical and easy to follow.

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?

Given the tool has a single parameter, no output schema, and moderate complexity, the description is remarkably complete. It covers input types, resolution behavior, edge cases (ISBN), return structure (despite no output schema), idempotency, rate limits, and API key authentication. No additional information is needed for correct invocation.

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%, so baseline is 3. The description adds significant value beyond the schema: it explains that non-DOI inputs are resolved server-side, ISBN always returns doi=null, batches are not accepted, and the identifier length constraints. This extra context elevates it to a 4.

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The description opens with a clear verb-resource pairing: 'Check whether a single scholarly work has been retracted, corrected, or had an expression of concern raised.' It distinguishes this tool from siblings by explicitly stating that no sibling tool overlaps this functionality (resolveIdentifier returns metadata but not retraction status).

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 gives explicit when-to-use guidance ('when the user asks 'has this paper been retracted?' or wants to verify a paper's standing before citing it'), when-not-to-use (for multi-paper audits, use loops; ISBN inputs always return no_doi; does not accept batches), and how to handle multiple papers ('loop one call per identifier'). It also mentions that no sibling tool overlaps this, reinforcing correct selection.

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