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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower; the description adds real value by disclosing what comes back (abstract excerpt, extracted findings, linked entities, supported/contradicted relations, related open questions). It stops short of describing error behavior for an unmatched ID or any size/shape limits on the payload.

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?

A single sentence with zero filler; the identifying constraint (one study, by known identifier) is front-loaded and the return enumeration follows as a compact clause.

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 no output schema, the description carries the burden of explaining the return value and does so adequately by listing the record's constituent parts. The remaining gap — behavior on a missing/ambiguous identifier and whether relations are summarized or inlined — is modest for a read-only lookup tool.

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 all three parameters are documented there, including their role as aliases of sid, so the schema does the heavy lifting and baseline is 3. The description restates the identifier formats but does not explain the id/study_id aliasing or note that all parameters are optional.

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?

States a specific verb+resource ('Full record for one study') and enumerates the record's contents, so an agent can distinguish it from search_studies and the other single-entity getters (get_entity, get_author, get_question) without opening a schema.

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 spelling out the accepted identifier space (Atlas ID, PMID, DOI, PMCID), which tells an agent it must already have a known study identifier. However, it never states when to prefer this over search_studies or what to do when the identifier is unknown — usage is implied rather than explicit.

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