Capture a PNG of the whole page or a specific element to document or verify its visual state. Use full_page for entire page or selector for one element, saving under data/screenshots.
Capture a PNG of the page (full page) or one element; saved under data/screenshots
| Name | Required | Description | Default |
|---|---|---|---|
| selector | No | ||
| full_page | No | ||
| save_path | No |
Changes observed during successful MCP inspections.
v2.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the behavioral disclosure burden. It does reveal that the tool produces a PNG and saves it under data/screenshots, which is useful. However, it does not explain default capture behavior, whether files are overwritten, or what is returned after the screenshot is taken.
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?
The description is a single efficient sentence with no filler. Key facts are front-loaded: the action, the target, the output format, and the default save location are all covered without redundancy.
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 tool has three optional parameters, no annotations, no output schema, and 0% schema description coverage. The description does not clarify the default capture scope (viewport vs full page), how selector and full_page interact, or what happens when both are omitted. More context is needed for an agent to invoke this reliably.
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 0%, so the description must compensate for the bare parameter names. It partially does: 'full page' maps to full_page, 'one element' maps to selector, and 'saved under data/screenshots' relates to save_path. But it never explicitly names the parameters or explains selector format, save_path handling, or default values.
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 uses a specific verb ('Capture') and resource ('page (full page) or one element') and identifies the output format as PNG. It does not explicitly name pdf_export as a sibling alternative, but the 'PNG' format distinguishes it from the PDF-focused sibling.
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 when to use the tool: when a PNG image of the page or an element is needed. It gives two capture modes, but it does not explicitly state when to choose this over pdf_export or other browsing tools, nor does it mention any exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.