Create openings (Opening tool)

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

Annotations only establish that this is a non-destructive, non-idempotent write. The description adds substantial behavior beyond that: wall openings extrude horizontally while slab/roof openings extrude vertically, 'Infinite' limit cuts through the whole host, default constraint varies by host type, and the return shape is [{guid, type} | {error}] in input order. This is rich, non-obvious operational detail.

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?

Dense but front-loaded: the core purpose comes first, then requirements, then host-specific behavior, then the API limitation and return format. Every sentence carries information, though the heavy parenthetical clauses make it slightly packed rather than crisply scannable.

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 output schema, the description compensates by describing the return value. It covers valid hosts, effective required fields, host-dependent defaults and orientations, the polygonal-shape limitation, and the anchor/position mechanics, so an agent has what it needs to call it correctly.

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 schema marks only 'owner' as required, so the description carries real weight by stating that width (and height unless circular) are also needed, and that 'point' or, for walls, 'position' must be supplied. It also clarifies the point/position relationship and the bottomElevation meaning for horizontal wall openings, adding semantics not guaranteed by the schema alone.

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 specific verb+resource (creates Opening-tool openings) and defines them concretely as rectangular/circular extrusion bodies that cut holes through a host, listing the valid hosts. This clearly differentiates it from siblings like create_windows, create_doors, create_skylights, and generic create_elements.

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?

Gives clear when-to-use context: shafts through slabs, service holes in walls/beams, and it explains that walls take 'position' while other hosts take 'point'. It also rules out custom polygonal shapes via the Archicad 26 API limitation. It does not, however, route the agent among alternatives such as create_windows/create_doors/modify_openings/get_host_openings.

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