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

Annotations already declare readOnlyHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds useful behavioral context: it lists returned plan elements, safety flags, and refusal conditions. It does not describe edge cases such as conflicting budget inputs or unknown supplement names, so it is not exhaustive.

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?

The description is front-loaded with the core purpose, then compactly covers inputs, outputs, and refusals. Every sentence carries useful information, and the repeated 'Read-only' is minor and aligned with annotations.

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 no output schema and 0% parameter description coverage, the description does substantial work by explaining return contents and refusal boundaries. It is broadly complete for invocation, though it omits finer details such as exact age-gate behavior and how goal/diet combinations alter recommendations.

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 0%, so the description must compensate. It names all seven parameters and clarifies that diet is optional and budget_per_month or budget_tier can be used, but it does not define goal/diet semantics, budget tier behavior, or exactly how current_supplements drives duplicate-ingredient checks.

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 gives a specific verb and resource: build a supplement plan for a fitness goal. The take/skip/optional framing and supplement-specific scope make it clearly distinct from plan_home_gym and shopping_list, though it does not explicitly name sibling alternatives.

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 clear usage context (fitness goal, optional diet/budget/region inputs) and explicit when-not cases by refusing medical, pregnancy, and medication scenarios. It does not route between sibling tools such as compare or shopping_list, so it falls short of full alternative guidance.

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