get_viewport_size

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

No annotations are provided, so the description carries the full behavior burden. 'Get' implies a read, but the description doesn't confirm read-only safety, describe the return format, or state whether this requires an active session. For a zero-annotation tool this is thin.

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 no wasted words. It is appropriately terse for an accessor tool, though brevity here borders on 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?

With no annotations, no output schema, and 0% param coverage, the definition omits what an agent needs: the sessionId requirement, the return shape (width/height), and confirmation this is a safe read. One short sentence is insufficient for the tool's context.

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% and the single sessionId parameter is undocumented in the description. The description says nothing about which session is queried or what sessionId must be, so it fails to compensate for the coverage gap.

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 clear verb+resource: 'Get current viewport size'. The word 'current' distinguishes it from a hypothetical set operation. Paired with the sibling set_viewport_size, the read/write split is inferable, though the description does not explicitly name the 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?

No when-to-use guidance or exclusions. There is no mention of the set_viewport_size sibling or when an agent should read vs write viewport dimensions. Usage is only implied by the verb 'Get'.

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