imgui_screenshot

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

With no annotations provided, the description carries the full burden. It states it saves a BMP file but doesn't disclose return behavior, whether the file is overwritten if it exists, permissions needed, or what happens on failure. The format parameter note that 'currently only bmp is supported natively' is a helpful transparency detail, but the overall behavioral disclosure is minimal for a file-writing operation.

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?

A single concise sentence that captures the core action, output format, and file-saving behavior. No wasted words. Could be slightly more informative about return values, but for a simple capture tool this is an efficient size.

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 tool with 2 optional params and no output schema, the description is mostly adequate. However, some behavioral details are missing (return value, overwrite behavior, whether the frame must be drawn first). The description doesn't fully cover edge cases like what happens with an empty frame or if the save fails. Adequate but not rich.

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 description coverage is 100%, so the schema documents both parameters well. The description itself adds marginal value beyond the schema — it confirms the output is BMP despite the format enum allowing ppm. The format parameter's note about only bmp being supported natively is meaningful but comes from the schema, not the description. Baseline of 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 verb (capture), resource (current ImGui frame), and output type (BMP file). It distinguishes reasonably from sibling tools like imgui_screenshot_widget and imgui_screenshot_annotated, which imply different screenshot variants. However, it doesn't explicitly name these siblings to differentiate.

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 implies this is a general frame-capture tool, and the schema confirms no required parameters. It doesn't explain when to use this vs. imgui_screenshot_widget or imgui_screenshot_annotated, though the sibling names suggest scope differences. No exclusions or alternatives mentioned explicitly, leaving the agent to infer distinctions.

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