screenshot

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

Discloses that the tool activates the window (brings to foreground) and uses fuzzy matching on title or class. However, does not mention error handling for missing window or behavior with multiple matches. Given no annotations, this is good but not exhaustive.

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?

Efficiently structured: main action first, then usage instructions, then parameter details. Every sentence adds value, no repetition or 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?

Covers all common use cases and parameters. Lacks mention of edge cases like window not found, but for a simple capture tool with no output schema, it is largely complete.

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?

With 0% schema coverage, the description fully explains both parameters: target enum with default and behavior, and window string with fuzzy matching and active window fallback. Adds meaning well beyond schema.

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?

Clearly states the tool captures a screenshot and returns the image directly. Distinguishes between full desktop capture and window-specific capture, with explicit 'single-call' instruction.

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 explicit when-to-use guidance: no arguments for full desktop, target='window' with window substring for specific window, and active window without window argument. Instructs not to list windows first, differentiating from sibling manage_windows.

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