time_day_of_week

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

No annotations are provided, so the description carries full burden. It states capabilities (day-of-week, occurrences, distance) but does not disclose behavioral traits like idempotency, error conditions, or performance characteristics. For a calculator, this is a notable gap.

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 (4 sentences) and front-loads the main purpose. It then expands on supported features and directs to more detail. However, the final sentence could be integrated or shortened.

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 no output schema, the description provides a reasonable overview but lacks details on return format or how to specify complex operations. The pointer to describe_tool partially compensates, but the description itself is not fully self-contained.

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 description coverage is 0%, so the description must clarify parameters. It mentions operations but does not explain valid ranges for year, month, day, or how to specify 'next N occurrences' (e.g., using operation parameter). The description adds some context but leaves ambiguity.

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's purpose with specific verbs: 'Find the day of the week...', 'list the next N occurrences...', 'measure the distance...'. It references a specific resource (dates) and distinguishes from siblings by mentioning supported calendar features (Proleptic Gregorian, ISO 8601, BCE).

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 lists three distinct operations but does not provide explicit guidance on when to use this tool versus alternatives (e.g., time_date_difference). It notes that full guidance is available via describe_tool, but lacks direct comparisons or exclusions.

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