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

With no annotations provided, the description carries the behavioral disclosure burden. It reveals the global scope ('across all contacts') and the sorting behavior (overdue first, then upcoming). While it doesn't explicitly say 'read-only,' the verb 'Find' and 'Returns' strongly imply a safe, non-mutating operation. This is adequate for a read/list tool.

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 two sentences long, front-loaded with the primary purpose, and every clause adds value. It avoids unnecessary detail and is immediately scannable.

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 simple list/read tool with no output schema, the description covers the key context: purpose, scope, and sort order. The optional parameters are well-documented in the schema, so the description doesn't need to restate them. It falls short of 5 only by not explicitly noting read-only behavior or defining 'overdue,' though the schema partially covers the latter.

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 100%, so the input schema already fully documents status, days_ahead, and include_overdue. The description adds no extra parameter-specific semantics, leaving the schema to carry the load—which it does effectively.

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: finding upcoming and overdue reminders across all contacts. The specific verb 'Find' and the resource 'reminders' make the action unambiguous, and the added detail about sorting (overdue first, then soonest upcoming) distinguishes this from reminder management tools like reminder_manage and upcoming_birthdays.

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 implies the tool is for viewing upcoming/overdue reminders, but it does not explicitly state when to use it versus alternatives. No exclusions or alternative tool references are provided, which is a clear gap given the sibling list includes reminder_manage for managing reminders.

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