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

Annotations already establish read-only, idempotent, non-destructive behavior. The description adds useful context by specifying the return format (pass/warn/fail counts, detailed rule results) and disclosing the payment model (fee only on successful non-error results). This goes beyond the structured 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?

The description is two sentences, both informative. The first sentence states the core purpose and returns, the second explains billing—a useful operational detail. No wasted words, and the information is front-loaded.

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 validation tool with a well-defined schema and no output schema, the description adequately covers return values and cost behavior. It doesn't elaborate on error cases or rule specifics, but the '38 Rules' in the title and the schema enums provide sufficient context for an agent to invoke it correctly.

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 input schema provides 100% coverage with descriptions for all three parameters, including enums for profile and platform. The description adds no additional parameter meaning beyond what is already in the schema, so the baseline score of 3 is 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?

The description clearly states the tool validates an avatar mesh file with a specific verb ('Validate') and resource ('avatar mesh file'), and mentions return counts and detailed rule results. However, it does not explicitly distinguish itself from sibling tools like axis_inspect or axis_manifest_verify, though 'validate' conveys a distinct intent.

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 only states what the tool does and its cost, but gives no guidance on when to prefer this over alternatives. It does not mention exclusions, prerequisites, or scenarios where a different tool (e.g., repair_mesh or axis_inspect) would be more appropriate.

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