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

Annotations already signal a non-read-only, idempotent, non-destructive mutation, and the description's 'Set/update' language is consistent. It does not disclose partial-update semantics, such as whether omitted fields are preserved, which is a meaningful gap for an all-optional-parameter tool.

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 a single sentence, front-loaded with the primary action and optional additions. It contains no filler and does not repeat schema details.

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 five optional parameters and no output schema, the description plus annotations cover safety and purpose. However, it leaves ambiguity about calling with no parameters and whether omitted fields are preserved, which is a moderate gap.

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%, with each parameter already documented (e.g., 'Look slug from list_looks'), so the description adds little beyond naming the same fields. Baseline 3 applies because the schema carries the parameter documentation burden.

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 uses a specific verb ('Set') and names the exact resources: look, persona, voice, plus optional name/bio updates. The phrase 'by default when entering rooms' clearly distinguishes it from style-changing siblings like change_style and reset_style.

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 clearly scopes the tool to configuring defaults applied when entering rooms, giving an agent a concrete trigger condition. It does not explicitly name alternatives or exclusions, but the context is sufficient to avoid confusion with current-style tools.

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