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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower, and the description still adds useful context: it renders the same workout card as list_workouts, giving output-shape consistency across tools. It does not, however, state what happens with an invalid or stale workout_id, so error behavior remains undisclosed.

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?

Purpose is front-loaded in the first clause and the behavioral instruction is a short, forceful sentence. The enumeration of four source tools is duplicated verbatim from the input schema, which is mild waste, but the text stays readable and earns most of its length.

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 an output schema present, the description does not need to explain return values, and it still notes card parity with list_workouts. The only material omission for a read tool operating alongside get_workout_details is a one-line distinction between the two, which an agent in this tool family will need.

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% for the single parameter, and the schema description already states the id must come from create_planned_workout, update_planned_workout, list_planned_workouts, or list_workouts. The description repeats that constraint ('exact workout_id') without adding format, validation, or failure semantics beyond the schema, so the 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?

It gives a specific verb+resource (returns one specific workout by exact workout_id) and ties the output to the list_workouts card format, so the agent knows what it produces. The gap is that the sibling get_workout_details exists and is never mentioned, so this tool is not fully differentiated from the closest alternative.

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?

Strong contextual routing: use it when the user asks to show/open/display a workout already identified in the conversation, and it explicitly discourages replying with a text summary when a valid workout_id exists. It also names the upstream tools that produce valid ids. It stops short of 5 because it never says when to prefer get_workout_details over this tool.

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