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

Annotations already declare readOnlyHint and destructiveHint, so safety is covered. The description adds meaningful behavioral context by specifying it returns the 'full block structure' and the source domains, which goes beyond the schema and annotations.

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 with no filler. The action, resource, scope, and purpose are all packed 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?

For a one-parameter read tool with annotations covering safety, the description is sufficient. It explains what it returns (block structure), the scope, and the intended use. Without an output schema, mentioning the block structure is enough guidance, though it could specify format.

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?

With schema coverage at 0%, the description must compensate. It identifies the parameter as 'by id' but does not elaborate on the id type or format. However, the single parameter is simple and the tool name clarifies it is a workout id, making this adequate for the minimal 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 clearly states the verb (read), the resource (workout by id), and explicitly scopes to catalog, collection, or the athlete's own library. It also conveys the purpose ('to inspect before scheduling or adapting'), which distinguishes it from plan-specific retrievals like get_plan_workout.

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?

It provides a concrete use case ('inspect before scheduling or adapting') but does not name alternatives or explicitly state when not to use it. The scope (catalog/collection/library) implies it's not for plan workouts, but that differentiation is not stated directly.

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