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

Annotations already declare this is a non-destructive, non-read-only, closed-world mutation, so the safety profile is covered. The description adds genuinely useful behavioral context — the default copy window is each class's own length starting the month after it ends — but it does not say whether new classes are created alongside originals, what happens on date conflicts, or whether the operation is reversible.

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 sentences with the core behavior front-loaded and the trigger condition second; nothing is padded. The phrase 'same everything' is slightly colloquial and could be tightened to a precise statement of what is carried over, but it does convey the idea compactly.

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 no output schema, the description is the only source for what a caller gets back, and it says nothing about the created classes or their identifiers, nor about the 1–500 batch limit beyond what the schema states. It covers the timing semantics well but is incomplete for a mutation tool that creates new entities.

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 baseline would be 3, but the description goes beyond the schema by explaining what happens when first_month and last_month are omitted (each class's own length, starting the month after it ends). That default-derivation rule is not present in the schema descriptions and directly affects how an agent should call the tool.

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 and resource ('Copy classes') plus the destination ('into their next span of months'), which is more precise than the title alone. It does not explicitly contrast with siblings like edit_classes or add_classes, but the copy semantics are distinct enough to be identifiable.

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?

'Use it when a year or term of classes is ending' gives one clear trigger condition, which is more than nothing. However, it names no alternatives and no when-not conditions (e.g., when to prefer edit_classes or add_classes instead), leaving routing to inference.

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