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

Annotations already declare destructiveHint=true and idempotentHint=true, but the description adds real context beyond them: the visible side effects (dashboard brand list, future post images) and the refusal mode for undersized images. It does not explain what becomes of a previously set logo, which matters given destructiveHint=true.

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?

Three tight sentences, front-loaded with the core action, then prerequisite, then side effects and failure mode. No filler and no repetition of the title or schema.

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?

With no output schema, the description carries return/behavior burden and does cover side effects, edge cases, and error behavior well. The remaining gap is replacement semantics for an existing logo on a tool annotated destructive, plus whether anything is returned on success.

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% and both parameters are already documented, including the 'from upload_brand_image' hint. The description's mention of assetId only echoes the schema, adding no format, size, or validation detail beyond it. 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?

States a specific verb and resource ('Sets a brand's logo from an existing image library asset') and immediately scopes the source of the asset, which distinguishes it from upload_brand_image and other brand-mutating siblings. The parenthetical clarifies the relationship to the sibling rather than restating the name.

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?

Explicitly routes the agent: 'upload_brand_image first, then pass its assetId here', naming the prerequisite alternative and the ordering condition. It also declares the no-brand-guide case is acceptable, removing a plausible reason an agent might avoid calling it.

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