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

Beyond the read-only/idempotent annotations, the description discloses request-order preservation, missing-slug reporting without substitution, and the data boundary on private lab results. These are meaningful behavioral details that affect how an agent interprets results.

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 concise sentences with no redundancy; the core resolution and comparison behavior is front-loaded, and the boundary condition is stated efficiently.

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 single well-documented parameter, output schema, and safety annotations, the description provides sufficient behavioral and boundary context. The only minor gap is not naming sibling alternatives, but the exact-slug wording is enough to route an agent correctly.

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 already documents the slugs parameter well with 100% coverage. The description adds value by specifying that slugs are resolved in request order and that missing slugs are reported rather than substituted, which clarifies expected behavior beyond the bare schema.

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?

Description clearly identifies a specific action: resolving exact public biomarker slugs for factual comparison. It differentiates from search/browse tools by emphasizing exact slugs, request order, and reporting missing slugs without substitution.

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?

Description provides clear context for when to use this tool: known public biomarker slugs needing exact comparison. It also gives a when-not boundary by excluding private lab results, though it doesn't explicitly name alternative sibling tools like search_biomarkers.

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