Skip to main content
Glama

resize_page

Resize a browser window to exact width and height for a specified page, ensuring accurate viewport dimensions for visual checks and testing.

Instructions

Resizes the page's window so that the page has specified dimension

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
widthYesPage width
heightYesPage height
pageIdYesTargets a specific page by ID.

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

B3.2/5.0
Behavior3/5

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

Annotations provide `readOnlyHint: false`, signaling this is not a read-only operation, and the description adds the outcome of resizing the window. However, it does not disclose side effects such as whether the page reloads, whether the viewport or the outer browser window is affected, or whether dimensions are in pixels. This adds some context but not rich behavioral detail.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single sentence with no filler and gets to the point immediately. Minor awkwardness in 'page's window' and the slightly redundant phrasing cost it the top score.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple three-parameter tool, the description is mostly sufficient: it names the action, target, and dimensions. Still, an agent would still need to assume units or infer from sibling context, since there is no mention of output, exact dimension semantics, or post-conditions beyond the minimal 'page has specified dimension'.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description's 'specified dimension' maps to `width` and `height`, but it adds no units, constraints, or relationship between the parameters beyond what the schema already states.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states a specific action ('Resizes') and a specific target ('the page's window') with named dimensions. It is unambiguous against most sibling actions, but it does not explicitly differentiate itself from dimension-related tools like `emulate`, so it stops short of a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives no guidance on when to use this tool versus alternatives such as `emulate`, `select_page`, or `navigate_page`. There is no mention of prerequisites, context, or exclusions, so the agent must infer intended usage purely from the tool name.

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