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

Annotations already declare readOnlyHint and destructiveHint, and the description adds valuable behavior beyond them: it is FREE, read-only, unknown ids error out, and the response contains both a ProfileDTO and a raw StudyRecord. No contradiction exists.

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 compact and front-loaded: it states the core operation first, then error behavior, then cost/safety, then the mirrored endpoint. Every sentence carries useful information with no 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 simple fetch-by-id tool with a single required parameter, the description is complete: it covers return shape, error semantics, read-only/free status, and the mirrored API route. The output schema exists, so return-value details do not need to be duplicated.

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% and the single id parameter is already documented with 'Catalogue id, e.g. S-01.' The description adds the 'Unknown id is an error' behavior, but does not add new parameter-level semantics beyond the 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?

The description states a specific verb and resource: retrieving 'One FieldStation study' by id, and specifies the exact return shape ('library-kit ProfileDTO plus the raw StudyRecord'). It is clearly distinct from the sibling list_studies, since it targets a single study.

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 the usage context: you must provide an exact catalogue id, and an unknown id is an error. However, it does not explicitly mention when to prefer this tool over vela.research.list_studies or name an alternative, leaving the routing decision somewhat implicit.

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