Dismiss Planner Item

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

Annotations already declare destructiveHint=false and idempotentHint=true, so safety and repeat-call behavior are covered. The description adds genuinely new context beyond that: the effect is scoped to the caller's own list only, and the item's state is not transitioned to done. It does not say whether a dismissal can be reversed, which keeps it short of 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 sentences, front-loaded with the action and followed by the scope qualifier; nothing is repeated from the schema and no sentence is 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 two-parameter mutation with a fully documented schema and annotations covering safety and idempotency, the description supplies the two things the schema can't: what is hidden (badge included) and whose data changes. Only the reversibility/undo path is left unstated.

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 both parameters are documented with their source ("from list_planner_items") and the type enum is fully enumerated in the schema. The description adds no parameter-level detail, so the baseline 3 applies.

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?

Specific verb ("Hide") plus specific resource ("an item from your Canvas To Do list and its 'new activity' badge"), with an explicit negative scope ("without marking it done") that separates it from the sibling mark_planner_item_done. An agent can select this over that sibling without opening either schema.

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 states the selection condition clearly: use this when the user wants an item off their To Do list but not completed. It doesn't name the alternative tool by name, but the contrast with marking done is unambiguous enough to route correctly.

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