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

Annotations only declare the generic safety profile (readOnlyHint=false, destructiveHint=false). The description omits the critical behavioral fact that this is step one of an upload flow that must be followed by media_upload_finish, and says nothing about what the returned presigned URL can be used for or its constraints.

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?

A single front-loaded sentence with no wasted words. It is efficient, though its brevity pushes missing detail into contextual completeness rather than being a fault of structure.

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?

An output schema exists, so return values need not be explained, but for a start-upload tool participating in a multi-step flow with dedicated media_upload_file and media_upload_finish siblings, the description should say the URL is used for a direct PUT and that the flow must be completed. That omission leaves the agent without the sequencing it needs.

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%, so all four parameters (fileName, contentType, projectId, workspaceId) are already documented in the schema. The description adds no meaning beyond 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?

Specific verb and resource: 'Get a presigned URL for direct file upload', plus a scoping hint ('for large files'). However, it does not differentiate itself from the obvious siblings media_upload_file and media_upload_finish, leaving the agent to infer the multi-step relationship.

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?

'for large files' implies a when-condition versus a smaller-file path, but the alternative (media_upload_file) is never named and no exclusions are given. Usage is inferable but not stated.

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