get_menstrual_last_confirmed

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds nothing beyond the schema, though it does not contradict the annotations. Useful context such as what is returned when no period has been confirmed, or the relationship to the confirm/update menstrual tools, is absent.

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?

A single short sentence with no wasted words, and the resource is front-loaded. It is efficient, though it errs toward under-specification rather than over-verbosity.

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?

For a one-parameter read-only tool with full schema coverage and annotations, the definition is minimally adequate: the agent knows what is fetched and for which date. It lacks any routing guidance among the numerous menstrual siblings and any note on behavior when no confirmed period exists.

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 single documented 'fordate' parameter (YYYY-MM-DD, UTC), so the schema carries the burden. The description's 'as of a date' only loosely echoes the parameter and adds no format or semantics beyond what is already documented.

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 phrase names a specific resource ('the last confirmed period') and scopes it to a date, so an agent can guess it retrieves a record rather than mutating one. However, it is a noun phrase with no verb and no differentiation from close siblings like get_menstrual_data_for_date or get_menstrual_cycle_summary, leaving the exact purpose ambiguous.

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?

There is no statement of when to use this tool versus the many other menstrual-data siblings (get_menstrual_calendar_data, get_menstrual_data_for_date, get_menstrual_cycle_summary, confirm_menstrual_period_start). The agent must infer usage entirely from the name.

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