Upload Mod Image (author)

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

Beyond the annotations (readOnlyHint=false, destructiveHint=false), it reveals the internal sequence (safety hash check, upload, media cache refresh) and the authentication requirement. This gives the agent useful expectations for side effects and failure modes.

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 main action is front-loaded in the first words, constraints are compact, and the internal workflow is packed into a colon-delimited list. Every segment earns its place; there is no 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 moderately complex mutation with no output schema, it conveys the essential context: target, file constraints, internal steps, and auth. It doesn't describe the return value or success/error behavior, and show_in_gallery is left unexplained, but an agent can still invoke the tool correctly.

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?

The schema already documents game, dry_run, and file_path, with 60% coverage. The description adds key constraints not in the schema: JPG/PNG/GIF and 8 MB limit for file_path, and 'YOUR mod' clarifies that mod_id must be owned by the authenticated author. show_in_gallery is still not explained.

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 uses the specific verb 'Upload' with the target resource 'an image ... to YOUR mod's gallery', and names the supported formats and size limit. This clearly differentiates it from siblings like delete_mod_image, upload_file_version, and add_mod_video.

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?

It gives clear usage context: this is for adding an image to the caller's own mod gallery, mimicking the mod editor, and only with the author's web session. It doesn't explicitly contrast with alternatives such as delete_mod_image or add_mod_video, so it misses the strongest when-to-use guidance.

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