zernio_upload_media_from_file

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

The description explains the sequence of operations (read file, get presigned URL, upload, return publicUrl) and lists supported file types. However, it does not disclose potential side effects (e.g., whether the original file is deleted), error conditions, or permission requirements. Given the lack of annotations, the description carries the full burden for behavioral disclosure, and it provides only the basic flow.

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 at four sentences, front-loading the purpose and usage guidance. It lists supported formats compactly. No unnecessary information. Slightly more structured formatting (e.g., bullet points) could improve readability, but current form is effective.

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 main workflow, usage scenario, and supported file types. It mentions the return value (publicUrl). However, it lacks details on error handling, file size limits, required permissions, and what happens to the original file after upload. For a tool with 3 parameters and no output schema, the description is adequate but not comprehensive.

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 coverage is 100% with clear descriptions for each parameter (e.g., filePath includes example absolute paths). The description adds value by explaining auto-detection of media type and the overall process, but it does not significantly enhance semantics beyond what the schema already provides. Baseline 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'), the resource ('local image or video file to Zernio'), and the method ('by reading it from disk'). It distinguishes from siblings by specifying 'when you have a local file path instead of a public URL', which is a key differentiator from tools like zernio_upload_media (presumably for URLs). Supported formats are listed, providing completeness.

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 says when to use this tool: 'when you have a local file path instead of a public URL.' It also explains the workflow (reads file, gets presigned URL, uploads, returns publicUrl). However, it does not explicitly state when not to use it or name alternative tools, which would earn a 5.

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