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

Adds substantial context beyond the annotations: up-to-a-minute latency, zero credit cost, no generation yet, unfit shots dropped with reasons, per-shot credit cost, and plan.note when facts are missing. Repeating the schema's locale and brand-kit defaults is the only drag; some redundancy with the structured fields.

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?

Front-loaded with purpose and payload, and every clause carries real information (latency, cost, exclusions, defaults). The density comes at a cost: one long run-on paragraph of semicolon-chained parentheticals that is harder to scan than the content warrants.

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?

No output schema exists, so the description carries the return-values burden and does so: it names the plan structure, credits, balance and missingFacts. Only gap is that it never says how to retrieve the plan later (get_image_set / check_image_set) or what failure modes exist for an invalid product or approved-only premium format.

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?

Well above baseline: it explains how aplus_format and aplus_text interact ("fields" returns copy per image to paste into Amazon fields) and how missingFacts changes what shots are produced. It does restate a few schema-documented defaults (locale, brand_kit_id, model_* defaults) rather than adding to them.

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?

States a specific verb and resource ("Creates an image set for a product and platform pack") and immediately names the return payload (shot plan, balance, missingFacts). The clause "Free; nothing is generated yet" cleanly separates it from the generation siblings in the same tool family.

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?

Gives concrete routing rules: "answer_facts first to add them" for the withoutFacts gap, "see store_look" for shopify, and the brand_kit_id default/"none" override. It implies but never names generate_image_set as the follow-up step after planning, so the workflow is slightly less than fully explicit.

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