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

Annotations already cover the safety profile (idempotent, non-destructive, open-world), so the bar is lower. The description still adds genuinely useful behavioral context beyond them: the flat $0.05/call cost and the photo-count bound. It does not disclose output shape, but an output schema exists to carry that.

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?

Two dense sentences that front-load the verdict composition before inputs and pricing. The parenthetical qualifiers are information-rich rather than filler, though the first sentence is heavy enough to slow parsing.

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 an 8-parameter, multi-photo tool with a nested questionnaire and an output schema, the description covers the essential inputs and cost, and the schema handles payment mechanics and return values. Only a brief note on the payment-requirement flow would make it fully self-contained.

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%, so the parameters are already documented. The description's '1-3 face photos, optional full-body + questionnaire' only restates what the schema says and adds no syntax or format detail beyond it, so the baseline 3 applies.

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 names a concrete deliverable (a combined seasonal-color + face-impression + body-frame styling verdict) with the four component rule sets spelled out, so an agent knows what it produces. It also implicitly distinguishes itself from portrait_analysis by being 'integrated', but it never explicitly contrasts with the sibling style_report, leaving some ambiguity.

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?

It states the input shape (1-3 face photos, optional full-body + questionnaire) and the price, which implies when the tool is applicable. However, it gives no explicit when-to-use vs alternatives or when-not guidance relative to siblings like style_report or portrait_analysis.

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