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

Annotations already declare this a safe, read-only, closed-world computation. The description adds genuinely useful context by naming the Mifflin-St Jeor equation and flagging that the result is an estimate, but says nothing about units of the returned values or precision, which matters for a numeric calculator with no output schema.

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?

A single tight sentence with the verb front-loaded and zero filler. It is appropriately sized for the tool, though it could have spent those words on sibling differentiation instead of re-listing inputs the schema already carries.

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?

Inputs are fully covered by the schema and annotations cover safety, but with no output schema the description should at least indicate what the two returned values are (BMR and TDEE, presumably kcal/day). It stops at 'estimate', leaving the agent to infer the return shape.

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 the schema already documents every parameter, including the activity multiplier example. The description merely lists the same inputs without adding format, range, or unit detail beyond what the schema provides; 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?

Names a specific verb (Estimate) and two resources (BMR and TDEE) and even pins the formula (Mifflin-St Jeor). However, it never distinguishes itself from close siblings like maintenance_calories, calorie, or bmi, which an agent would need in order to pick correctly.

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?

No when-to-use guidance and no exclusions. The description does not tell the agent when BMR/TDEE is the right choice versus maintenance_calories or calorie, which sit right next to it in the tool list.

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