get_hydration

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

No annotations are provided, so the description carries full behavioral burden. It discloses the output structure (byDay with consumedML, goalML, etc.) and the fact that it covers hydration only, not food water content. It is transparent about the tool's behavior without contradictions.

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 concise, using a single paragraph of about four sentences. It is front-loaded with the main purpose and efficiently adds necessary details without 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?

Despite the absence of an output schema and annotations, the description sufficiently covers input parameters and output structure. It explains the key fields and the scope of data, though it could mention error handling or empty results.

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%, but the description adds value by explaining the exclusive relationship between 'date' and the 'from'/'to' pair, and by expanding on valid date formats. This goes beyond what the schema provides.

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 tool retrieves the user's water intake with individual entries and per-day totals against a saved goal. The verb 'Get' and resource 'hydration' are specific, and it distinguishes itself from sibling tools like log_hydration and get_nutrition_log by focusing on hydration data.

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 explicit usage scenarios (e.g., 'how much water have I had today?') and clarifies what the tool does not cover (food water content). It explains date formats and parameter combinations, but does not explicitly compare to sibling tools for when not to use it.

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