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

Goes beyond the annotations by disclosing that the call is not retried (so a failure is final), that it returns the new reminder id, and the underlying POST endpoint. It does not explain failure modes or what the destructiveHint=true means for a create operation, leaving a small gap.

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?

Front-loaded with 'WRITE:' and packed into one dense sentence plus two short fragments; every clause (linking options, default remindee, no retry, return value, endpoint) carries information an agent needs.

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?

With 8 parameters and no output schema, the description supplies the key facts an agent needs (required vs optional linking, defaults, return value). It stops short of describing error behavior or what validation of the date/description fields will reject.

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 value by stating that links are optional and that reminder_type/remindee_user_id default when omitted. That default-behavior context is not in the schema.

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?

States a specific verb+resource ('create a follow-up reminder (task)') with its scope: due date, optional links to contact/property/listing, and assignee. This clearly separates it from rex_search_reminders and rex_get_reminder, which read rather than create.

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 when to use it (you want a new reminder) and notes the default remindee when no user is supplied, but it never states when NOT to use it or points to an alternative. Usage is inferable rather than explicit.

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