Skip to main content
Glama
fixed-width

glass

by fixed-width
OverviewSchemaSourceRelated ServersDiscussionsAdmin
Rust

glass_scroll

Scroll the UI container at (x,y) by horizontal or vertical wheel notches, with optional modifier keys. Specify steps as notches, not pixels, to control zoom or distance.

Instructions

Scroll the container under (x,y) by horizontal/vertical wheel notches, optionally holding modifiers. Notches are not pixels. For 2+ known steps, use glass_do.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
xYesWindow-relative anchor x; selects the container under the pointer.
yYesWindow-relative anchor y.
dxNoHorizontal wheel notches, -100 through 100 (positive right, negative left); typically 1-5, not pixels.
dyNoVertical wheel notches, -100 through 100 (positive down, negative up); typically 1-5. App determines distance/zoom.
modifiersNoHeld modifiers, e.g. ["ctrl", "shift"].

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed5 schema fields changedv1.8.0
    • changedInput schema / properties / dx / description
      Previous value: -"Horizontal wheel notches from -100 through 100, not pixels.\nPositive is right and negative is left, repeated `|dx|` times.\nTypical values are 1–5."New value: +"Horizontal wheel notches, -100 through 100 (positive right, negative left); typically 1-5, not pixels."
    • changedInput schema / properties / dy / description
      Previous value: -"Vertical wheel notches from -100 through 100, not pixels.\nPositive is down and negative is up, repeated `|dy|` times.\nTypical values are 1–5.\nApps choose how a notch maps to lines, pixels, or zoom."New value: +"Vertical wheel notches, -100 through 100 (positive down, negative up); typically 1-5. App determines distance/zoom."
    • changedInput schema / properties / modifiers / description
      Previous value: -"Modifier keys to hold during the action, e.g. [\"ctrl\"] or [\"ctrl\",\"shift\"] for multi/range-select."New value: +"Held modifiers, e.g. [\"ctrl\", \"shift\"]."
    • changedInput schema / properties / x / description
      Previous value: -"Pointer x the wheel is aimed at, window-relative — apps scroll the container\nunder this point, so it selects which pane moves."New value: +"Window-relative anchor x; selects the container under the pointer."
    • changedInput schema / properties / y / description
      Previous value: -"Pointer y the wheel is aimed at, window-relative. See `x`."New value: +"Window-relative anchor y."
  2. Changed6 schema fields changedv1.5.1
    • changedInput schema / properties / dx / description
      Previous value: -"Horizontal scroll in **wheel notches** (discrete clicks — small integers like 1–5, NOT\npixels). Positive `dx` sends wheel-right, negative wheel-left; glass clicks `|dx|` times."New value: +"Horizontal wheel notches from -100 through 100, not pixels.\nPositive is right and negative is left, repeated `|dx|` times.\nTypical values are 1–5."
    • addedInput schema / properties / dx / maximum
      Added value: +100
    • addedInput schema / properties / dx / minimum
      Added value: +-100
    • changedInput schema / properties / dy / description
      Previous value: -"Vertical scroll in **wheel notches** (discrete clicks — small integers like 1–5, NOT\npixels). Positive `dy` sends wheel-down, negative wheel-up; glass clicks `|dy|` times. How\nan app maps a wheel notch to its view (lines, pixels, zoom) is the app's choice."New value: +"Vertical wheel notches from -100 through 100, not pixels.\nPositive is down and negative is up, repeated `|dy|` times.\nTypical values are 1–5.\nApps choose how a notch maps to lines, pixels, or zoom."
    • addedInput schema / properties / dy / maximum
      Added value: +100
    • addedInput schema / properties / dy / minimum
      Added value: +-100
  3. Changed3 schema fields changedv1.2.0
    • addedInput schema / properties / x / description
      Added value: +"Pointer x the wheel is aimed at, window-relative — apps scroll the container\nunder this point, so it selects which pane moves."
    • addedInput schema / properties / y / description
      Added value: +"Pointer y the wheel is aimed at, window-relative. See `x`."
    • removedInput schema / title
      Removed value: -"ScrollArgs"
  4. Addedv1.0.3

TDQS

A4.7/5.0
Behavior4/5

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

Annotations already declare readOnlyHint=false and destructiveHint=false, indicating a mutating but non-destructive operation. The description adds that scrolling uses wheel notches rather than pixels, which clarifies the effect. It does not describe potential side effects or error conditions, but given the annotations cover the safety profile, the added context is sufficient.

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

Conciseness5/5

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

Two concise sentences: the first states the purpose and key parameters, the second clarifies units and provides the alternative. No wasted words, and the critical scoping information is front-loaded.

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

Completeness5/5

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

For a single-scroll action with no output schema, the description covers the purpose, the alternative for multi-step sequences, and the unit semantics. Nothing essential is missing for an agent to invoke it correctly.

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

Parameters4/5

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

Schema coverage is 100%, so the schema already documents all parameters including dx/dy as notches. The description reinforces the 'not pixels' distinction, which adds a critical clarification beyond the schema's 'wheel notches' wording. This adds value without redundancy.

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

Purpose5/5

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

The description clearly states the action ('Scroll the container under (x,y)') with a specific verb and resource, and distinguishes itself from the sibling glass_do by explicitly noting when to use that alternative. It also clarifies the unit of measurement (notches vs pixels), which is essential for correct usage.

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

Usage Guidelines5/5

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

It gives explicit guidance on when to use an alternative: 'For 2+ known steps, use glass_do.' This directly informs the agent of the boundary between this tool and a related sibling. It also clarifies the notches unit, which is a usage constraint.

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

Deploy Server

Other Tools