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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive) and openWorldHint=false, so the bar is lower. The description still adds real behavioral detail beyond them: no pagination regardless of week count, how repeated workout_id uses collapse into one item with day labels, and that the same workout_id across weeks denotes reuse of one saved workout.

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 sentences, front-loaded with the core action, and every sentence carries information: scope, no-pagination guarantee, and the grouping/reuse semantics of the returned structure. 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?

With an output schema present, return-shape explanation is optional yet the description usefully clarifies the compact grouping model. The only real gap is failure behavior for an unknown program_id, which is minor for a read-only single-resource fetch.

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 program_id's type, minLength and 'Stable id of the saved program' meaning are already documented. The description adds nothing about the parameter (e.g., where the id comes from), 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?

States a specific verb+resource: fetching one saved program's complete plan. The word 'one' and 'complete' implicitly contrasts with the sibling get_programs listing tool, but no sibling is named explicitly, so it stops short of a 5.

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 by the word 'one saved program': an agent infers this is the drill-down after get_programs. There is no explicit when-to-use, when-not, or named alternative such as get_programs or get_workout_detail.

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