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

readOnlyHint already declares this is a safe read operation, and the description adds the API endpoint and return wrapper shape. It omits auth requirements, not-found behavior, and rate limits, which would add richer behavioral context.

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?

Three short sentences with the core operation front-loaded and no wasted text. The endpoint and return shape are useful supplements, not padding.

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 single-resource read tool, this is nearly complete: identifier, endpoint, and return wrapper are covered, and annotations handle safety. Error/not-found behavior is the main omission.

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 the single uuid parameter is already documented. The description restates that lookup is by uuid but adds no format or validation details 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?

States a specific verb and resource: fetch a single user by uuid, and clarifies donor/supporter meaning. It does not explicitly differentiate from get_authenticated_user or list_users, so it stops short of full sibling distinction.

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 uuid' for a single-user lookup, but the description does not state when to use this instead of get_authenticated_user or list_users. No exclusions or alternatives are provided.

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