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

The description adds useful behavioral context beyond the annotations: the first brief takes a few minutes, the card under the reply waits and fills in, and the agent should say it is being written and stop. However, the annotations mark this as destructive, and the description does not explain what state is changed or what could be destructive about starting the day.

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 front-loaded with purpose, then gives trigger phrases, parameter semantics, and async workflow guidance in a short sequence. Every sentence contributes either invocation guidance or operational behavior, with no filler.

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 no-output-schema tool with a single optional enum parameter, the description covers purpose, invocation triggers, parameter meaning, and the asynchronous card behavior. The main remaining gap is that the destructive annotation is not explained, so an agent cannot tell what the tool may overwrite or alter.

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?

Although schema coverage is already 100%, the description adds meaningful semantic detail for the enum values: relationship covers who needs a reply or nudge and that a note is written; branding covers who engaged with posts and that a next post is drafted. This goes beyond the schema's terse 'The brief they asked for' label.

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 uses a specific verb and resource: turning on the user's 'Your day' and starting their first brief from their inbox. It clearly distinguishes this activation flow from related siblings such as my_day or send_daily_briefing by focusing on the initial brief-generation action.

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?

It gives explicit triggering phrases: when the user asks to start Your day, their morning brief, relationship brief, or personal branding brief, or says yes to one. It does not name when-not-to-use cases or competing sibling tools, which keeps it below a 5.

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