log_hydration

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

No annotations provided, so description carries full burden. Discloses behavioral traits: date parsing formats, deduplication (identical calls within an hour treated as same entry), mutual exclusivity of amountOz/amountML. Does not mention authentication or rate limits, but covers key behaviors.

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?

Description is long but well-organized with clear sections (first sentence, 'USE THIS', 'PASS EITHER', 'Common volumes', 'DATE/TIMEZONE', 'DEDUPLICATION'). Every sentence adds value and is front-loaded. Could be slightly more concise but structure is effective.

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 4 parameters, no output schema, and complexity (date parsing, dual units, deduplication), the description covers essentials: when to use, parameters with examples, date handling, dedup rules. Minor gap: no mention of return value, but overall comprehensive.

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% with good descriptions. The description adds value beyond schema: common volume conversions (cup=8 oz, etc.), requirement to pass EITHER amountOz OR amountML, date format details, and deduplication hints. Adds substantial context for parameter selection.

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 logs water or hydrating drink volume into the user's hydration tracker, distinguishes from log_food_entry by explaining that the 'water' field in food entries does not count toward the hydration ring. It provides specific usage examples like 'I had a glass of water' and 'log 16 oz of water'.

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?

Explicitly says 'USE THIS — not log_food_entry' when the user mentions drinking water. Provides scenarios for when to use both tools (e.g., protein shake should log both food and fluid). Includes guidance on date/timezone parsing and deduplication.

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