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

Annotations mark the tool as readOnlyHint=false and destructiveHint=false, so the description carries the burden of explaining behavior. It states the tool creates a signed URL for direct GCS upload, which implies the actual upload happens client-side, but it does not disclose URL expiry, return format, or other side effects. This is adequate but not rich.

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?

The description is a single sentence with zero filler. The core action ('Create a signed URL') and key scope (image formats, GCS) are concentrated and front-loaded. This is ideal for a low-complexity utility tool.

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 straightforward utility with fully documented parameters and no output schema, the description covers the essential purpose and scope. It could explicitly note that this only generates the URL without uploading the image, but that is already implied by 'signed URL for uploading'. The optional extraCaptureRequestId is documented in schema, so nothing essential is missing.

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% – all parameters (id, fileName, contentType, extraCaptureRequestId) are documented in the schema. The description adds no additional parameter-level meaning beyond what is already in the schema, so the baseline of 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 clearly states the action ('Create a signed URL'), the resource (an image upload URL), and the scope (PNG, JPEG, WebP, SVG images, direct to GCS). This distinguishes it from sibling URL creators like createClarityDocumentUploadUrl or createClarityVideoUploadUrl by explicitly listing image formats, so an agent can reliably identify it.

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?

The description implies usage through the listed image formats, but it gives no explicit guidance on when to prefer this tool over siblings like createFileUploadUrl or createClarityDocumentUploadUrl. There are no alternative names or exclusion conditions. The agent must infer the use case from the format list alone.

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