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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds real context beyond that: the underlying REST path (GET /v2/activity/workout/{workoutId}) and the required scope read:workout, which tells the agent about auth prerequisites. It stops short of error/rate-limit behavior.

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?

Two compact sentences, front-loaded with the core action and field list, followed by endpoint and scope. Efficient with essentially no filler, though the parenthetical field dump is slightly dense.

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 single-resource read with one fully documented parameter and no output schema, the description covers the resource, the identifying key, the response fields, the endpoint, and the scope. Only error/pagination behavior is absent, which is minor here.

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 documented in the schema (UUID format, source tool). The description only restates 'by its id', adding no new syntax or format meaning beyond the schema. Baseline 3 applies.

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 ('a single workout by its id') and enumerates the returned fields (sport, strain, heart rate, distance, zone durations, start/end). The 'single' scoping implicitly separates it from the list_workouts sibling.

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 only implied: an agent understands it needs a workoutId, and the schema notes the id can come from whoop_list_workouts. There is no explicit when-to-use vs when-to-prefer-list guidance or any exclusion in the description itself.

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