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

No annotations exist, so the description carries the full burden; it discloses the return shape (grams per day, the band, and which body-weight basis was used) and the liability/scope boundary. What is missing is any statement about how the activity level changes the output or what happens with out-of-range inputs for a tool that otherwise behaves like a pure calculation.

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 sentences, front-loaded with the computation, then the return value and disclaimer. No filler or redundancy.

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 correctly explains what comes back, and the disclaimer covers the safety framing for a health-adjacent calculation. The only real hole is the unexplained activity enum, which an agent cannot resolve from either structured field or prose.

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 67%: weight_kg and height_cm are documented in the schema, and the description only restates that height 'sharpens it'. The 'activity' parameter is an enum with no description in the schema and no explanation in the description of what light/active/strength mean or how they shift the target, leaving the one parameter that most affects the result semantically opaque.

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 ('work out a daily protein target'), names the population and context (weight loss on a GLP-1), and names the inputs. It is clearly distinguishable from siblings like energy_tdee, weight_ideal, and bmi_check without opening any schema.

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?

Gives a clear condition for use ('someone losing weight on a GLP-1') and a scope boundary ('general information, not personalised dietetic advice'). It does not name alternative tools or state when-not to use it, e.g. versus energy_tdee for calorie targets, so it falls short of full routing guidance.

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