mark_day_complete

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

Annotations already indicate mutability, idempotency, and non-destructive nature. The description adds context that this is a toggle operation. No contradictions exist. It could be improved by noting any error conditions or state dependencies.

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 minimal and efficient: a one-line purpose followed by two concise lines explaining parameters. No unnecessary words or repetition.

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 purpose and parameter semantics adequately. Since an output schema exists, return details are not required. A small gap is the lack of mention of behavior for non-existent dates, but the tool is simple enough.

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?

With 0% schema description coverage, the description fully compensates by specifying the date format (YYYY-MM-DD) and the boolean role for complete. This adds essential meaning beyond the schema's type definitions.

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 'Mark' and the resource 'diary day', and specifies the action as toggling complete/incomplete. It distinguishes itself from sibling tools which are mostly getters or food-related operations.

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 no guidance on when to use this tool versus alternatives. It does not mention prerequisites, contextual triggers, or exclusions, leaving the agent without clear decision criteria.

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