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

Annotations already indicate destructiveHint: true. Description adds valuable context: confirm parameter requirement, permission checks, business type restrictions, and resubscribe link display. This goes beyond annotations by detailing prerequisites and side effects.

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?

The description is 8 sentences, covering purpose, prerequisites, warnings, and constraints. It is detailed but not overly verbose; every sentence adds value. Could be slightly more concise, but the information density justifies the 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?

Given no output schema, the description covers all necessary context: what the tool does, required inputs (confirm value), permissions checks, business restrictions, and pre-action steps. It is complete for a destructive tool.

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 0% description coverage, so description must compensate. It explicitly states that confirm must be 'DELETE', but does not explain communityId and customDomainId beyond the tool name and context. While helpful, it leaves some interpretation to the agent.

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 'Delete an external custom domain from a managed community', using a specific verb and resource. It distinguishes from siblings like 'delete_business_custom_domain' and 'disconnect_custom_domain' by specifying the community context and the term 'external custom domain'.

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?

Provides explicit instructions: requires confirm set to 'DELETE', advises checking business permissions via 'check_business_tool_access', notes that FREE businesses cannot use the tool, and instructs to show grace-period warning and resubscribe link. This offers clear when-to-use and when-not-to-use guidance.

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