left_click

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

With no annotations, the description carries the full burden. It accurately describes a left-button click at coordinates, which implies pointer movement and a single press/release, but it does not explicitly disclose side effects, click duration, or coordinate-space behavior. It is not misleading, only minimal.

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 one short, front-loaded sentence with no filler. It immediately communicates the core action and target, making it easy for an agent to parse quickly.

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?

For a simple input action, the description plus the fully documented schema is sufficient for correct invocation. The description could explicitly say 'single click' to rule out double_click, but the sibling names and straightforward action make that gap minor.

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 x, y, and modifiers are already well documented. The description adds nothing beyond the generic notion of coordinates, which is acceptable because the schema carries the parameter meaning.

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 states a specific verb ('click'), the exact resource ('left mouse button'), and the target ('specified coordinates'). This clearly distinguishes it from sibling tools like right_click, middle_click, and mouse_move, and aligns directly with the tool name.

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 is given about when to use this tool versus alternatives such as double_click, left_click_drag, or mouse_move. The description only says what the action is, not when an agent should select it or when it should prefer a sibling.

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