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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is known. The description adds genuinely new behavioral context: the deletion is permanent, deleting a variant/destination cascades to everything inside it, and user confirmation is required beforehand. It stops short of describing error modes or auth requirements, so not quite 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?

Three sentences, front-loaded with the destructive scope, then usage routing, then the cascade warning. No filler and every sentence carries actionable information.

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, no-output-schema tool, the definition covers what it deletes, when to prefer it over siblings, the cascade risk, and the confirmation requirement. Combined with annotations and full schema coverage, an agent has everything needed to invoke it safely.

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% and the schema itself documents conditional requirements (kind for option, eventKey for event, destinationKey for destination/option) plus the optionKey/optionId naming quirk. The description adds only the target-type list, which the schema already covers, 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?

States a specific verb (permanently delete) and enumerates the exact resources it applies to: variant, destination, destination option, event. This clearly distinguishes it from siblings like update_destination_option, toggle_event, and select_destination_option.

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?

Explicitly states when to use it ('only when the user rejects something outright') and names the alternatives for the softer case ('deselect the option or toggle the event instead'). It also sets a prerequisite: confirm with the user first for cascading deletes.

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