screenshot

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

No annotations exist, so the description carries the full burden. It implies a non-destructive read, but says nothing about what is actually captured (viewport vs. entire desktop), whether OS-level screen-recording permission is required, or how the image is returned. For a capture tool the scope and side-effect profile are the key unknowns and both are omitted.

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?

One short, front-loaded sentence with no filler. It is appropriately sized for the operation, though its brevity is a symptom of under-specification rather than disciplined economy.

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?

There is no output schema, so the description should explain what comes back (raw image data, file path, URL), yet it does not. The ambiguous scope of 'current screen' combined with the silent return contract leaves real gaps for an agent invoking this tool.

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% and the single 'format' parameter is already documented with its enum and png default, so the schema does the heavy lifting. The description adds nothing about format semantics; baseline 3 applies.

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 ('Capture') and resource ('screenshot') with a scope qualifier ('of the current screen'). It is trivially distinguishable from siblings (click, type, scroll, browser_open), though it never explicitly differentiates itself since no sibling competes for the same function.

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?

No guidance on when to use this versus, e.g., browser_open or any other observation mechanism, and no prerequisites or conditions given. 'Current screen' implies a context but never states which context (browser viewport vs. full desktop).

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