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

Annotations already declare destructiveHint=true and openWorldHint=true, so the safety profile is covered. The description adds real behavioral context beyond that: the student receives a push notification and the effect mirrors the in-app action. It stops short of stating reversibility or failure behavior, which is what keeps it from a 5.

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?

Two short clauses, front-loaded with the action and followed by the side effect and the confirmation requirement. "Like in the app" is slightly loose but earns its place by anchoring the behavior to a known surface.

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 destructive, single-parameter tool with full annotations and full schema coverage, the description covers what gets affected (student notified) and the pre-call safety step. No output schema exists, so unexplained return values are acceptable.

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% and the single parameter is already documented as "Appointment id from get_schedule", a useful cross-reference the description does not need to repeat. The description adds nothing about parameter meaning, so the baseline 3 is correct.

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 opens with a specific verb+resource, "Cancels a class", which an agent can distinguish from reschedule_class or confirm_class. It never names those siblings explicitly, so differentiation is inferred rather than stated.

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?

"Confirm with the person first" is a genuine usage precondition that tells the agent to verify the human before invoking. However, it gives no guidance on when to cancel versus reschedule_class or reject_class_change, so the alternative-selection decision is left unaddressed.

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