confirm_menstrual_period_start

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

Annotations already declare readOnlyHint=false (a write), destructiveHint=false, and openWorldHint=true; the description's mention of POST merely corroborates the mutation hint without adding new information. It says nothing about auth requirements, idempotency, whether re-confirming overwrites an existing start date, or side effects on the cycle calendar.

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 dense sentence with no filler, and the positive path is front-loaded ahead of the exclusion clause. It is efficient, though the content is developer/endpoint-oriented rather than agent-oriented.

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 mutating tool with no output schema, 3 required params, a nested object, and low schema coverage, the description omits critical context: what the call changes, required prior state, units for cycle/period lengths, and what happens when the date is not a real period start. An agent cannot safely call this on the description alone.

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 only 25% — only periodStartDate carries a format note (YYYY-MM-DD UTC). cycleLength, periodLength, and the nested options.predictedCycle object are undocumented in both schema and description, and the description adds no units, ranges, or meaning for them despite the low coverage requiring compensation.

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 identifies the HTTP method and the exact endpoint path, and it names the sibling sub-paths it is NOT (dayview/calendar/lastconfirmed/summary), which helps disambiguate from the get_menstrual_* readers. However, it never states in human terms that this confirms/sets a menstrual period start date, so the actual purpose must be inferred from the tool name and URL.

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 'NOT the ... sub-paths' clause gives a when-not signal, implicitly steering the agent away from the read-only menstrual endpoints. But there is no positive when-to-use guidance, no prerequisites (e.g. must cycle be initialized via init_menstrual_cycle_setup), and no mention of consequences of calling it.

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