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

With no annotations, the description carries the full burden and does so well: it discloses output shape (UTC plus local times), ranking logic, partial-window fallback, DST-change reporting, zone-count limits, and even payment requirements. This is unusually complete behavioral context.

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 dense and front-loaded, starting with the use case and then parameters, output, example, and pricing. It is efficient, though the single-paragraph packing of example URL and payment details makes it slightly cramped.

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?

There is no output schema, but the description fully explains the return value: JSON overlap windows, local times, ranked one-hour slots, partial windows, and DST changes. Combined with complete schema coverage, an agent has everything needed to call and interpret the tool.

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%, so the baseline is 3. The description adds useful meaning beyond the schema: it gives example zone formats (IANA/KST/PST/CET), notes the first zone is the anchor, and restates defaults for working hours. It does not add much on include_weekends or date behavior beyond the schema, so it is strong but not exhaustive.

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 states a specific verb and resource: finding working-hour overlap across time zones for scheduling. It clearly distinguishes itself from nearby tools like time_convert and time_business_days by focusing on multi-zone meeting-window calculation and ranking.

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?

It opens with a clear usage condition: 'Use when scheduling a meeting across time zones.' It does not explicitly name alternatives or when not to use it, but the context is strong enough that an agent can route correctly.

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