mfp_set_water

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

Annotations already mark this as a non-read-only, non-idempotent write. The description adds useful behavioral context: setting an absolute cup count for a day, optional date defaulting to today, the cup-to-ml unit conversion, and a confirmation-message return. It does not deeply discuss overwrite semantics, but 'Sets' plus annotations provide reasonable coverage.

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, front-loaded with the main action, and organized with Args/Returns sections. Every sentence earns its place: purpose, unit clarification, parameter details, and return type.

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 setter tool, the description provides the essential information needed to invoke it correctly: cups value, optional date, default behavior, unit system, and return message. It omits explicit error or overwrite notes, but those are not critical given the schema constraints and annotations.

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 top-level schema has 0% description coverage, the description explicitly breaks out the nested SetWaterInput fields with types, an example value, the optional date format, and default behavior. This compensates for the top-level gap, even though much of it mirrors the schema's nested property descriptions.

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?

Description opens with 'Log water intake for a specific date' — a specific verb and resource, and further clarifies the exact action by saying it sets the number of cups consumed for the day. This clearly differentiates it from siblings like mfp_get_water (retrieval) and other food/measurement tools.

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 clearly establishes when to use the tool: when logging or setting water intake for a date, with cups and an optional date. It does not explicitly name alternative tools or state when not to use it, so it stops short of a 5.

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