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

Annotations already indicate idempotent and non-destructive. The description adds the requirement of explicit confirmation, which is a behavioral guard. It does not contradict annotations, but it doesn't disclose other behaviors like side effects or error handling, so it adds limited value.

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?

Single sentence, front-loaded with the usage trigger, and no fluff. It's appropriately concise.

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 mutation tool with three required parameters and no output schema, the description is minimal. It doesn't explain the idempotency_key purpose, prerequisites beyond confirmation, or what happens on success/failure. Given the complexity, it is incomplete.

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 has zero description coverage, so the description must explain parameters. It implies event_id (the event) and confirmed (explicit confirmation), but does not mention idempotency_key at all. Thus it provides partial but insufficient parameter semantics.

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 action: adding one Dizko event to the connected user's persistent plan, with the condition of explicit confirmation. It distinguishes from siblings like plan_night or save_event by specifying 'persistent plan', but it doesn't explicitly name alternatives, so a 4 is appropriate.

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 provides a trigger condition ('when a user confirms they want to add... only after explicit confirmation') which gives clear context for use. However, it does not mention alternatives or when not to use this tool, so it lacks explicit exclusion guidance.

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