get_nutrition_summary

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

Annotations already declare readOnlyHint and openWorldHint, and the description adds substantial semantics beyond them: days without logged intake are never treated as 0 kcal, means are computed over logged days only, device burn is an estimate, and calorie balance does not measure fat change. These are non-obvious caveats an agent must know to interpret and present results correctly.

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?

Front-loads purpose before diving into per-day and per-window output details, then caveats, then a method reference. It is dense and semicolon-heavy, but nearly every clause carries distinct information relevant to a 9-parameter analytics tool; trimming further would lose signal.

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, the description carries the full return-value burden and does so explicitly, enumerating the per-day fields (kcal, macros, burn, balance, weight) and per-window aggregates (totals, means, days without intake, weight change/slope in kg/week). It also points to the method guide, leaving no material gap for correct invocation.

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%, so the parameters are already documented in structured form. The description reinforces a few points (default 28-day span, configurable custom field codes, balance fallback), but largely restates what the schema already conveys, so it sits at the coverage-driven baseline.

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 names a precise resource and scope: food intake, calorie balance and weight trend over a period, with per-day and per-window breakdowns. This clearly separates it from the training/wellness siblings by domain. It stops short of naming a sibling alternative (e.g. get_wellness_trends, get_fueling_analysis) to disambiguate, so it falls just under the top mark.

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?

"Use for food intake, calorie balance and weight trend over a period" is an explicit usage trigger and the default 28-day window and read-only nature set expectations. There is no when-not guidance or named alternative for overlapping tools, which keeps it out of the 5 band.

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