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

Annotations already mark it as read-only, non-destructive, and idempotent. The description adds useful behavioral context: it is just a link, the user enters their address on the page, no card is required, and it explains the notification timing. This goes beyond the annotations without contradicting them.

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 the key purpose and includes necessary details in a single sentence. It is slightly dense but every element (free, address entry, timing, no card) earns its place.

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 zero-parameter informational tool with a clear read-only annotation, the description provides everything an agent needs: what it is, who it is for, how it works, and what the user must do. No gaps remain.

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?

With zero parameters, the baseline is 4. The description does not need to explain parameters, and it appropriately describes the user action on the linked page instead.

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: a sign-up link for free Chicago street cleaning alerts. It distinguishes itself from the schedule lookup sibling by focusing on reminders and the sign-up mechanism, not on retrieving dates.

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 specifies the target audience ('For people who want reminders to move their car for street cleaning'), giving clear context for when to use it. However, it does not explicitly name alternatives (e.g., street_cleaning_schedule) or when not to use it.

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