Model summary

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds genuinely useful context beyond them: results reflect the *visible* model 'after policy' (i.e., filtered by access policy), and the call is 'cheap, bounded'. That policy-filtering nuance is exactly the kind of behavioral trait annotations cannot express.

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 sentences, front-loaded with the returned contents and then the usage recommendation; no filler. The phrase 'cheap, bounded' is slightly marketing-flavored but still earns its place as cost guidance.

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?

There is no output schema, but the description explicitly enumerates the return contents, and the policy-filtering caveat plus boundedness tells the agent what to expect. Nothing essential for calling this tool correctly is missing.

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 top_psets and top_types are already documented with defaults. The description adds no additional meaning about these parameters, which is acceptable at the baseline when the schema carries the load.

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 enumerates exactly what the tool returns (schema, authoring application, units, storeys, element counts by type) and explicitly positions itself as the discovery/first-call tool versus the more targeted siblings like bim_elements_by_type or bim_property_values. An agent can tell what this does and why it differs from the other bim_* tools without opening the schema.

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?

It gives a clear when-to-use signal ('the right first call... before it starts guessing names at them'), which is strong positive guidance. It does not name a when-not case or name specific sibling alternatives to avoid, so it falls just short of a 5.

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