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

Annotations already flag destructiveHint=true, but the description adds substantial behavior beyond them: the internal two-step mechanism (getDailyWeighIns then looped deleteWeighIn), the exact conditions that yield null (zero entries, or multiple entries without deleteAll), and the count return. This tells the agent precisely what gets destroyed and when nothing happens.

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?

Purpose is front-loaded and the content is valuable, but 'IRREVERSIBLE' is stated twice and the return value is described redundantly ('returns how many went' then 'returns the count'). Trimming that duplication would tighten the definition without losing information.

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?

No output schema exists, and the description correctly covers return values (count or null). For a destructive mutation tool it explains irreversibility, confirmation, and the deleteAll gate. The only missing piece is its relationship to the delete_weigh_in sibling.

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 50%: cdate is documented in the schema, but deleteAll has no schema description. The description compensates by explaining deleteAll's effect — without it, more than one entry deletes nothing; with it, every entry that day is removed.

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?

States a specific verb (deletes) and resource (weigh-ins) with the scope constraint (recorded on one date) plus the return value. It is distinguishable from the singular delete_weigh_in by the date-based bulk semantics, but it never names that sibling to make the distinction explicit.

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?

Provides a clear procedural rule ('IRREVERSIBLE: confirm with the user before calling') and describes the deleteAll gating behavior. However, it gives no guidance on when to prefer this tool over delete_weigh_in or the alternatives in the sibling set, leaving routing to inference.

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