obs_monitor_list

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

No annotations exist, but the description richly discloses behavior: index instability across replugging, the fact that projectors cannot be closed via API, and the surprising consequence of a projector appearing over OBS's own window. This is excellent behavioral documentation beyond what any schema could convey.

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?

Two paragraphs, both earn their place. First sentence states the action and its context. The rest adds critical warnings and fallback guidance. Zero fluff, but it does use 2-3 sentences to explain why — well worth the space.

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 and no output schema, the description covers the full picture: what the tool does, how to interpret results (index, count), and what operational decision to make (windowed vs fullscreen). The workaround for the API limitation (cannot close projector) is exactly the kind of context that makes a tool usable. It also references sibling tools by not needing them, which is fine.

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?

Zero parameters, so the schema covers everything. The description adds a helpful baseline example (one 1920x1080 display) and explains the index meaning, which would help an agent interpret output. Slightly shy of 5 because the description doesn't detail the return format (e.g., list of monitor objects) but that may be overkill for a zero-param tool.

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 is exceptionally clear: it states the tool lists physical displays with their indices for fullscreen projectors, explicitly noting positional instability and the lack of a query to find the monitor with the main OBS window. It is distinct from siblings like obs_projector_open_mix or obs_screenshot by focusing on enumeration, not action.

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 explicitly instructs calling this tool before opening a fullscreen projector, warns when not to use it (single monitor) and provides an explicit alternative (use windowed mode when count is 1). This goes beyond generic context and directly addresses when to use this tool vs. alternatives.

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