prepare_images

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

Annotations already declare non-readonly, non-destructive, non-openWorld, but the description adds genuinely useful behavior beyond that: it crops around assets.key_art_focus, never stretches, reports upscaling, never generates artwork, and writes output plus a preview page to .steam-mcp/exports/images/. It stops short of stating overwrite behavior or whether existing files are replaced.

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?

Front-loaded with the core action and dense with useful specifics; every clause conveys something concrete. Slightly long but no filler or repetition, so it stays efficient.

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?

With an output schema present, return values need not be described, and the description still tells the agent where files land and that a preview page is produced. The main gap is the unexplained 'only' and 'path' parameters, otherwise this is adequate for the task.

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 0%, so the description carries the full burden and largely fails. It explains the achievement_icons behavior (256x256 JPG with greyscale locked versions), but 'only' and the required 'path' parameter are never clarified, leaving two of three params undocumented in both schema and prose.

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?

States a specific verb+resource ('make every store, library and icon image... plus achievement icons') and names the exact input assets (assets.key_art, assets.logo, assets.overrides) plus the output location. It even distinguishes itself from generative siblings by stating 'never generates artwork'.

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?

Usage context is implied (produce Steam-ready images for the user to upload) and the input sourcing is clear, but it never routes the agent explicitly against siblings like generate, export_package, or apply. No when-to-use-vs-alternative or prerequisite guidance is given.

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