create-upload-session

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

Annotations already declare destructiveHint true and readOnlyHint false, so the bar for additional disclosure is lower. The description adds useful context about the pre-authenticated upload URL and the optional body with conflict behavior, but does not elaborate on side effects, session lifecycle, or required permissions beyond what annotations imply.

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 concise, front-loaded with the core purpose, and uses a helpful tip icon to highlight the main use case. Every sentence adds value without unnecessary detail.

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 covers the primary purpose, return value, and key usage scenario. With no output schema, it provides enough to understand the tool's behavior, though it omits details like session expiration or how to use the uploadUrl, which might be expected.

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 high (83%), so parameters are largely documented in the schema. The description adds an example path and conflict behavior, but does not systematically explain each parameter beyond what the schema already provides.

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 creates an upload session, with a specific use case ('For large file uploads (no size limit)') and the key output ('Returns a pre-authenticated uploadUrl for direct PUT of file bytes'). This distinguishes it from siblings like upload-file-content and create-mail-attachment-upload-session.

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 explicitly indicates when to use it ('For large file uploads') and provides the URL path pattern for new files. It does not explicitly mention alternatives or when not to use it, but the context implies it is for large uploads requiring a session rather than direct uploads.

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