explain_recurrence_rule

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

No annotations are provided, so the description carries the full burden. It clearly states the tool is non-destructive and read-only ('Nothing is scheduled or executed'). This is sufficient for a simple explanation tool, though details about the output format (plain English description) are missing.

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 extremely concise: two sentences that convey the purpose and key behavioral trait. No unnecessary words.

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 the tool's low complexity (single parameter, no output schema), the description covers the essential aspects: input format, action, and non-execution behavior. It differentiates from sibling tools like 'validate_recurrence_rule' and 'explain_cron_expression'. A minor gap is the lack of output description, but for a simple explanation it is acceptable.

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% with a clear description of the 'rule' parameter including format and example. The tool description does not add extra meaning beyond the schema, so a baseline score of 3 is appropriate.

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 function: 'Describes an iCalendar recurrence rule (RRULE) in plain English.' The additional sentence 'Nothing is scheduled or executed' reinforces the scope and distinguishes it from scheduling-related siblings like 'next_recurrence_occurrences'.

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 explicitly states that the tool only explains rules and does not schedule or execute anything, guiding the agent to use it for explanation purposes. It implicitly differentiates from siblings like 'explain_cron_expression' by specifying iCalendar RRULE, but does not list alternative tools for other cases.

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