Get Total Fat

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

Annotations already provide readOnlyHint and idempotentHint, and the description adds valuable behavioral context by stating the return is a single value per 100 g, which clarifies output shape and rationale (context efficiency). This goes beyond the annotations without contradicting them.

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, no filler, front-loaded with the key action and resource. Every word adds value, and the structure is appropriately minimal for a simple tool.

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?

For a simple read-only tool with one parameter and an output schema present, the description covers the essential behavioral and outcome aspects (single value, per 100 g, minimizes context). No gaps that hamper proper use.

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?

With zero schema description coverage, the description carries the burden but only indirectly explains fdcId as 'a FoodData Central entry.' It doesn't explicitly state that fdcId is the identifier or provide format details, though the single parameter is self-explanatory given the tool name and context.

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 clearly states a specific verb ('Return'), resource ('FoodData Central entry'), and the data returned ('per 100 g total fat'). It distinguishes itself from sibling nutrient-specific getters by emphasizing the single value per 100 g, making the tool's purpose unambiguous.

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 description implies when to use the tool (when needing total fat per 100 g) and mentions 'to minimize context usage,' which hints at a benefit over more comprehensive tools. However, it does not explicitly name alternatives or state when not to use it, leaving the comparison to the user.

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