vrchat_avatar_update

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

Goes well beyond the destructiveHint annotation by detailing no-undo behavior for asset fields, tag merge semantics that preserve author tags, clearContentTags removing unknown content tags, and two-directional releaseStatus risks (public leak / private breakage). No contradiction with annotations.

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?

Every sentence earns its place: it front-loads the core action, then provides essential caveats about asset fields, tag behavior, releaseStatus, and dryRun. The structure is logical and dense without redundancy.

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 the tool's 8 parameters, mutation risk, and nuanced tag behavior, the description is remarkably complete. It covers scope, restrictions, edge cases, risk warnings, and a preview mechanism. An output schema exists, so the lack of return-value detail is acceptable.

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 covers 100% of parameters, but the description adds critical semantics: the exact content tag enum values, the merge/replace behavior for tags, the role of clearContentTags, the dual dangers of releaseStatus, and the purpose of dryRun for previewing. This far exceeds the baseline.

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?

Opens with an explicit verb and resource: 'Edit your own avatar metadata', and enumerates exactly which fields are editable (name, description, releaseStatus, content tags). It also distinguishes itself from read-only siblings like vrchat_avatar_profile and clarifies that asset fields are out of scope.

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 clear context: this is for editing your own avatar's metadata, and it explicitly excludes asset fields. It gives warning conditions (releaseStatus risks, tag merge behavior) that guide when to be cautious, though it doesn't name alternative tools or state a 'when not to use' beyond scope.

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