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

The description discloses an important moderation behavior: a moderated request causes an immediate, permanent, no-appeal handle lock and restores the auto-generated handle. This describes a destructive outcome, but the annotations declare destructiveHint=false, creating a direct contradiction. Because the description contradicts structured annotations, it scores 1 under the rubric.

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 short sentences, front-loaded with the action and followed by the critical moderation consequence. Every sentence adds meaning with no wasted wording.

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 simple one-parameter mutation tool, the description covers the core action and the most important adverse side effect. It leaves minor gaps around alternatives and parameter formatting, but those are partly covered by the schema.

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?

The single handle parameter has 0% schema description coverage, though the schema provides a regex pattern for format. The description only says 'any available valid custom handle' and does not explain what 'available' means, how availability is checked, or what format constraints apply.

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 states a specific verb and resource: changing the user's handle to a custom handle. It is clear enough to distinguish from generic profile updates, though it does not explicitly reference the sibling update_profile tool.

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?

There is no explicit guidance on when to use this tool versus alternatives such as update_profile, and no prerequisites or exclusions are stated. Usage is only implied by the verb 'Change your handle'.

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