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

Annotations already mark the tool as read-only and non-destructive, so the bar is lower. The description adds useful behavioral context beyond annotations: it returns upcoming events only, includes volunteer shifts and registration closure status, and is scoped to the active school. It does not contradict annotations and provides enough behavioral framing for a list operation.

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 three sentences long and each sentence earns its place: the first states what is returned, the second explains how the returned IDs connect to downstream tools, and the third provides alternative-tool routing and the optional filter. It is front-loaded and free of 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 read-only listing tool with an existing output schema, two optional parameters fully documented, and clear annotations, the description covers everything an agent needs: return contents, relationship to dependent tools, alternatives for own registrations, and optional filtering. Nothing important is missing.

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 schema documents both optional parameters (start_date and end_date) adequately. The description only says 'Optionally filter by date range,' which adds no new semantic detail beyond the schema's own descriptions. Baseline 3 is appropriate given full schema coverage.

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 lists upcoming events for the user's active school and enumerates the included data (date, times, location, volunteer shifts, registration status). It distinguishes itself from related registration/signup tools by explicitly noting that event IDs feed register_for_event and shift IDs feed sign_up_for_volunteer_shift.

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 gives explicit routing guidance: it says to use list_my_event_registrations / cancel_my_event_registration and list_my_volunteer_signups / cancel_my_volunteer_signup to review or undo the user's own registrations and signups. This tells the agent exactly when this tool is appropriate and when alternatives should be used.

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