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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds a terse 'Returns: {thresholds}' note, but it is a placeholder rather than meaningful behavioral context and the output schema already covers return shape.

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 short sentences with the core purpose front-loaded and no filler. The trailing list_bundles pointer is arguably waste for this tool, keeping it short of a 5.

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?

An output schema exists, so return values need not be explained. However, with 0% schema description coverage and a structured foods input, the description leaves the agent without guidance on the required per-food fields, which is a real gap for calling the tool correctly.

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% and the single 'foods' parameter is an array of objects whose required fields (name, gi, carbs_g, portion_g) are undocumented in both schema and description. 'Per food and total for a meal' hints that input is a per-food list, but it does not explain the required per-item fields or their units/ranges.

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 and resource ('Calculate glycemic load (GL)') and clarifies the scope as 'per food and total for a meal', which distinguishes it from generic nutrition calculators like calculate_recipe_nutrition. It does not explicitly name a sibling it is not, but the meal-level GL framing is specific enough to identify the tool.

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?

The only guidance is 'See list_bundles for related cuisine calculators', which is an off-topic pointer that does not tell the agent when to use this tool versus alternatives such as calculate_recipe_nutrition. There are no conditions, prerequisites, or exclusions.

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