Upload File

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

Annotations include openWorldHint: true and destructiveHint: true, which already inform the agent about external interactions and potential destructive behavior. The description adds context about the base64 encoding requirement and that Canvas performs a multi-step upload internally. However, it does not disclose details like overwrite behavior, return values, or failure modes. Given the annotations, the additional context is useful but not comprehensive.

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 two sentences long, front-loaded with the primary action, and contains no redundant or filler content. Every sentence adds value: the first defines purpose, the second provides an encoding requirement and expectations about internal processing.

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 core purpose and a key constraint but omits potentially useful operational details such as return value, error behavior, or handling of existing files with the same name. The schema and annotations provide good baseline coverage, but for an upload tool with no output schema, it would be helpful to know what happens on success or failure. It is adequate for selection but not fully complete.

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%, with all parameters documented, so the schema carries the heavy lifting. The description reinforces that 'content' must be base64-encoded, which is already stated in the schema, and adds no new parameter-specific information. Thus it meets the baseline of 3 for high schema coverage.

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: 'Upload a file to a course.' This is a specific verb+resource construction that distinguishes it from sibling tools like download_file, delete_file, and list_files. It adds relevant constraints (base64 content) and a behavioral note about internal multi-step handling.

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 by stating its purpose, but it does not explicitly specify when to use this tool over alternatives or mention any exclusions. For example, it doesn't say 'use download_file to retrieve files' or note scenarios where uploads are not appropriate. The usage context is inferred from the tool name and description, but no direct alternative guidance is provided.

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