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 covered. The description adds real context beyond them: a GM-only permission requirement and a stated return value ("the memorial state"), both of which the agent cannot infer from the structured fields. It does not explain what a reverted completion does to participants or memorial entries.

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?

Four short fragments, no filler, with the core effect stated first and the permission/return details after. The telegraphic phrasing ("Take the completion off") is slightly awkward but costs no length.

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 one-parameter toggle mutation with no output schema, the definition covers effect, authorization, inverse operation, and return value. The only soft spot is that "the memorial state" is never explained, so the agent knows a return exists but not its shape.

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?

There is a single parameter with 100% schema description coverage, including slug-or-id guidance, so the schema already does the work. The description adds nothing about the campaign argument, making the baseline 3 appropriate.

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?

"Take the completion off" states the reverse of completing a campaign, and combined with the name/title the operation is unambiguous. It implicitly distinguishes itself from the sibling complete_campaign ("Completing again puts it back"), though the phrasing is informal rather than a clean verb+resource statement.

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?

"GM only" gives a clear authorization precondition, and "Completing again puts it back" tells the agent the inverse tool (complete_campaign) exists and how the two interact. It stops short of stating when-not-to-use or what happens to dependent data, so it is clear context rather than a full decision guide.

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