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

Beyond the annotations (which only mark it non-read-only, non-destructive), the description discloses concrete behavioral traits: the upload is private, signed, capped at 10 MiB, expires after 2 hours, and is consumed via a PUT to the returned uploadUrl. These are exactly the operational constraints an agent needs and are not derivable from 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?

Two sentences, zero filler, with the verb+resource front-loaded and the size/expiry/workflow details packed into the follow-up. Every clause earns its place.

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 multi-step upload tool with no output schema, the description does a good job of covering the full flow from preparation through PUT to downstream handoff, effectively describing the returned uploadUrl/pdfPath. It omits any mention that brandId is effectively required and says nothing about failure modes or cleanup of an expired upload.

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 coverage is 0% for the single brandId parameter, so the description must compensate. 'For this brand' gives only a loose hint that brandId selects the target brand; it adds no format, source, or required-ness detail, leaving the parameter largely undocumented in both places.

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 states a specific verb and resource ('Prepare a private signed PDF upload for this brand') and immediately situates itself in a workflow by naming the downstream tools (add_content_source, create_content_from_source). An agent can distinguish it from create_brand_kit_upload or upload_brand_logo without opening any schema.

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 gives clear operational context: PUT bytes to uploadUrl, then pass pdfPath to add_content_source or create_content_from_source. That sequencing is genuinely useful routing guidance, but it never states when this upload path is preferable to alternatives or any preconditions, so it stops short of explicit when/when-not guidance.

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