list_monitors

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

With no annotations, the description carries the behavioral burden. It discloses return format (index, position, size) and the important nuance that index 0 is the virtual bounding box. This goes beyond a bare 'list' description and sets expectations about the special index.

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?

Only two sentences, front-loaded with the primary purpose, followed by return details. Every sentence adds value without waste.

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?

Given zero parameters, an output schema exists, and the description fully covers the key behavioral nuance (index 0 bounding box), the description is complete for the tool's complexity. Sibling tools about screen interaction benefit from this geometry info.

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?

The tool has zero parameters, so the baseline of 4 applies. The description contributes nothing about parameters, but none are needed, and the schema already confirms no parameters.

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 clearly states 'List available monitors and their geometry' with a specific verb and resource. It distinguishes itself from sibling tools by being the only tool that deals with monitor enumeration.

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 usage context: when monitor geometry is needed, call this tool. It doesn't explicitly mention alternatives or exclusions, but the context is clear given the absence of other monitor-related tools.

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