take_screenshot

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

Annotations only supply readOnlyHint=false, so the description carries the burden of behavioral disclosure and adds none. It doesn't say where the image lands (attached to the response vs. written to disk via filePath), whether the target page must be active, or how large captures are handled. Only the schema hints at these behaviors.

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 front-loaded sentence with zero waste, but it is undersized for a six-parameter tool with a file-writing side effect. Concision here shades into under-specification.

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?

The required pageId and the main option set are covered by the schema, and there is no output schema to explain. What's missing is guidance on the response/attachment behavior and on which capture target to choose for which intent, which matters for a tool with six interacting options.

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 all six parameters are already documented, including the uid/fullPage incompatibility and quality's irrelevance to PNG. The description's only added semantic is the page-vs-element choice, so baseline 3 is right.

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 and resource ('take a screenshot') and distinguishes the two capture targets (page vs. element). It does not differentiate itself from nearby siblings like take_snapshot or screencast_start, which capture similar visual state in different forms.

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 prefer this over take_snapshot, screencast_start, or evaluate_script, and no mention of prerequisites such as an active page selection. The page-vs-element distinction is only implicitly conveyed by the phrase 'or element'.

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