Compare two days

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds value beyond annotations by specifying the exact nutrients computed and that deltas are returned by meal type, providing context on what the tool accesses and produces.

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 main function in the first sentence and a practical use case in the second. No wasted words.

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?

The description covers the tool's purpose, returned nutrients, and meal type breakdown. However, without an output schema, it does not describe the response structure (e.g., format of deltas), but this is acceptable for a straightforward diff tool.

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 67% (date_a and date_b have descriptions, response_format has none). The description adds no extra parameter information beyond the schema, so it meets the baseline for moderate coverage.

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 the verb 'compute', the resource 'per-nutrient diff between two days' summaries', and lists specific nutrients and meal type breakdown. It distinguishes itself from sibling tools like nourish_daily_summary and nourish_weekly_summary by focusing on comparison.

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 provides a clear use case ('how was today vs yesterday?' coaching). However, it does not explicitly state when not to use the tool or mention alternative siblings, leaving some ambiguity for an AI agent.

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