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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered by structured data. The description adds genuine value by disclosing what the record contains (abstract excerpt, extracted findings, linked entities, supported/contradicted relations, open questions), which is exactly the kind of return-shape context an agent needs when there is no output schema.

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 front-loaded sentence that leads with the resource and key, then enumerates contents. Every clause earns its place given the absence of an output schema.

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 one fully documented parameter, rich annotations and no output schema, the description does the heavy lifting by listing the returned fields. It could go slightly further on error behavior for an unknown ID or on record size, but it is essentially complete for a simple read.

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 parameter is fully documented in the schema itself, so the baseline is 3. The description's example ID ('SAB1994') merely echoes the schema's own example and adds no new syntax or format guidance.

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 (get) and resource (one study) plus the lookup key (Atlas ID), and enumerates the record's contents. An agent can immediately distinguish this single-record fetch from search_studies.

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?

Usage is implied by 'by Atlas ID' — an agent knows to call this when it already has a study identifier and wants the full record rather than a search result. However, it never explicitly contrasts with search_studies or states prerequisites (e.g. that the ID must come from a prior search).

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