upload_local_file

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

No annotations are provided, so the description must fully disclose behavioral traits. It mentions the endpoint and return value but omits critical details such as file size limits, supported file types, permissions required, whether the operation is idempotent, or if the uploaded file is publicly accessible. This lack of depth limits the agent's understanding of side effects.

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 extremely concise, consisting of two sentences that convey the core purpose and key output. No unnecessary words or redundant information. The structure is front-loaded with the main action.

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?

While the description explains the return value (fileMetadataId), it lacks details on error handling, synchronous vs asynchronous behavior, file size constraints, and behavior when uploading duplicate files. For an upload tool with no output schema, more context is needed to ensure correct agent usage.

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?

All three parameters are fully described in the input schema (100% coverage). The tool description does not add additional meaning beyond what the schema already provides. For example, the schema already explains that account overrides cookies.json. Baseline score of 3 is appropriate.

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 (upload a local file to Grok storage), specifies the endpoint via path, and explains the return value (fileMetadataId) and its use as a reference in chat messages. It is distinct from sibling tools, none of which are file upload tools.

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 when a local file needs to be uploaded for later reference in a chat message, but it does not explicitly state when to use this tool versus alternatives like create_media_post. No when-not or exclusion guidance is provided.

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