Upload an image for a TikTok comment

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

Annotations declare readOnlyHint=false, openWorldHint=true, destructiveHint=false; the description adds substantial context beyond that — the all-three-must-be-passed-back constraint, 5MB/format/dimension limits, and the TikTok account authorization requirement. No contradiction with 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?

Purposefully front-loaded with the core purpose, followed by operational constraints in a dense but relevant sequence. Long for a single-parameter tool, yet every clause (dimension matching, limits, auth) is operationally necessary; nothing is filler.

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 simple one-param tool with no output schema, the description is fully self-sufficient: it explains the return trio, the coupling requirement, size/format/dimension limits, the local-file conversion path, and the authorization prerequisite. Nothing an agent needs to invoke it correctly is missing.

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%; the schema already describes imageUrl as a public URL and mentions upload_file. The description repeats slightly more detail (that upload_file produces such a URL) but does not add meaningful semantics beyond what the schema 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 opens with a specific verb+resource: 'Turn a public image URL into the imageUri that comment_on_tiktok_video needs.' It states exactly what the tool produces (imageUri plus dimensions) and immediately names the consuming sibling tool, so an agent can tell it apart from upload_file and other upload utilities.

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?

Provides clear context: it is a prerequisite step for comment_on_tiktok_video, notes when a raw URL will be rejected (new comment vs. reply), and points to upload_file for local files. It does not name explicit exclusions or 'when not to use' beyond the auth caveat, so it stops short of a full 5.

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