Scale an ingredient list

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

Beyond the annotations (readOnly, openWorld, idempotent, non-destructive), the description discloses substantial behavioral details: it does not contact any website, rounds quantities to readable values, rounds countable items to whole/half units, and leaves lines without quantities untouched and flagged. This is rich context that helps the agent predict the tool's behavior.

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?

The description is front-loaded with the primary action and contains five focused sentences. Each sentence adds a distinct piece of information: the core function, input options, scope, behavior on quantities, and a recommendation. No filler or redundant language.

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?

Given the tool has a well-annotated schema, an output schema, and annotations, the description covers all necessary aspects: purpose, input modes, edge cases (pinch, no quantity), and manual-alternative guidance. It is fully sufficient for an agent to select and invoke 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?

Although the schema already provides descriptions for all parameters (100% coverage), the description adds meaning by explaining the relationship between factor and the from/to servings pair, and by describing how the ingredients parameter is processed (rounding, handling approximate quantities). This goes beyond the schema's basic 'Multiplier to apply' and 'How many servings are wanted'.

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 opens with a specific verb and resource: 'Rescale a list of ingredient lines to a different number of servings.' It clearly distinguishes from sibling tools (search_recipes, get_recipe) by focusing on scaling rather than searching or retrieving. The mention of working on any French ingredient list further clarifies the domain.

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 gives explicit usage options: 'Give either factor directly, or from_servings and to_servings and the factor is computed.' It also provides an alternative to the tool: 'Prefer this over doing the arithmetic yourself.' This clearly signals when the tool should be used (for scaling ingredient lists) and provides a comparison to manual calculation.

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