Request a presigned upload URL for a digital file

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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the safety profile is partially covered. The description adds genuinely new behavioral context: an explicit rate limit of 100 requests / 10 seconds per shop with a link, plus the two-phase workflow requirement that the upload is incomplete until the confirm call runs.

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 tight sentences plus a one-line rate-limit note; every sentence earns its place and there is no filler. Minor deduction because the leading rate-limit notice precedes the purpose statement rather than following it.

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 9-parameter, nested-schema tool with no output schema, the description covers the workflow, the rate limit, and the required confirm step. It does not mention the confirm_digital_file_upload sibling by name, but with full schema coverage and annotations the definition is sufficient to call the tool 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?

Schema description coverage is 100% across all 9 parameters, including the nested payload object and the size/header matching constraint, so the schema carries the semantics. The description only references uploadUrl indirectly and adds no parameter-level meaning beyond what the schema already states. 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 states a specific verb and resource: 'Returns a presigned URL to upload a digital file to.' An agent immediately knows this is the first step of a two-step upload flow. It does not, however, distinguish itself from the sibling request_media_upload_url, which follows the same pattern for images.

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 sequencing context: receive the URL, PUT the file bytes to uploadUrl, then call the confirm endpoint to link the file to the product. That is actionable workflow guidance. It stops short of exclusions or naming alternatives (e.g., the media-upload sibling), so it is not a full 5.

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