Upload an image or video

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

Beyond the annotations (readOnlyHint=false, idempotentHint=false, destructiveHint=false), the description discloses important behavior: it creates an upload, returns three distinct URL types, supports optional auto-deletion via expiresIn, and returns errors as normal tool errors rather than exceptions. This gives the agent a clear behavioral model without contradicting the annotations.

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 dense but every sentence contributes: accepted types, size limits, input modes, mutual exclusivity, return URL purposes, and error behavior. It is front-loaded with the core purpose and then details the constraints. No filler or redundant restating of the title.

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?

For a tool with 4 optional-looking parameters, practical constraints, an output schema, and no explicit required fields, the description fully compensates. It clarifies the real requirement (either path or base64+filename), describes what the agent can expect as output, and covers failure modes. The agent can invoke this tool correctly with minimal additional inference.

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?

Although schema description coverage is 100%, the description adds critical semantic constraints not visible in the schema: path and base64+filename are mutually exclusive, filename is required with base64 but inferred from path, and expiresIn controls auto-deletion. It also explains what the return URLs mean, adding value beyond the raw parameter definitions.

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 states a specific verb and resource: 'Upload an image or video to YourImageShare and get back a shareable link.' It clearly distinguishes this tool from its siblings list_uploads and delete_upload by focusing on the creation/upload action rather than listing or deleting.

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 gives clear context for when to use this tool: uploading images/videos, with accepted formats and size range. It also explains the two input modes (path vs base64+filename) and when each is appropriate, including the 'never both' rule. It doesn't explicitly name sibling alternatives for when-not-to-use, but the upload vs list/delete distinction is obvious.

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