screenshot_fiji

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

Describes how each mode works (Robot for full_screen, rasterize for active_image, render as PNG for results_table) and notes headless limitations. No contradiction with annotations (readOnlyHint=true).

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?

Two concise sentences: first states purpose and modes, second gives usage guidance. Front-loaded with essential information, no fluff.

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?

Given the tool's simplicity (one enum parameter) and presence of output schema, the description covers all necessary context, including headless usage and what each mode captures.

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 has high coverage (100%). The description adds headless-friendly context for results_table, which goes beyond the schema, justifying a score above baseline.

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 tool captures pixels for verification and lists three distinct capture modes (full_screen, active_image, results_table). It differentiates from sibling tools like compare_screenshots and get_image_info.

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?

Explicitly advises using active_image or results_table when running headless without a display, providing clear context for when to use which mode.

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