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

The description discloses that the actual upload happens outside the MCP, which clarifies the tool's limited scope. However, it does not mention any side effects, required permissions, or potential side effects (e.g., whether the URL is ephemeral or tied to a creation). The annotations provide no hints, so the description only partially covers behavioral transparency.

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, focused sentence with no redundancy. It conveys the essential information (step 1, presigned URL, external upload, next step) efficiently and is well-structured.

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?

The description provides enough context for a basic understanding, especially by mentioning the dependent next step. However, it does not describe the return value (the presigned URL format or count), nor does it address error handling or edge cases. Given the lack of an output schema, it is not fully complete but acceptable for a simple step.

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?

The description does not explain the 'count' or 'mimeType' parameters. It only hints at 'URL(s)' implying count might be the number of files, but the required 'mimeType' is left undefined. The schema provides no descriptions either, leaving users to infer parameter meanings.

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 tool's function: obtaining presigned PUT URLs for uploading files, and it identifies the tool as the first step in a two-step process. It uses specific verb ('get') and resource ('presigned PUT URL(s)'), making the purpose unambiguous.

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 provides usage context by indicating this is for local/user files and explicitly mentions the sequential flow (upload externally, then call creations_finalize_upload). It implies when to use this tool, though it does not explicitly contrast with alternatives or mention when not to use it.

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