get_entity_counts

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

No annotations are provided, so the description carries the full burden. It discloses performance traits ('cheap', 'Instant') and implies a read-only operation via 'census', but it does not explicitly state that the tool makes no changes to the drawing or describe any error conditions or limitations. Some behavioral context is present but not comprehensive.

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?

The description is a single, front-loaded sentence that combines purpose and usage guidance efficiently. Every word contributes meaning ('Instant', 'cheap', 'census', 'per type', 'call this FIRST'). There is no filler or redundancy.

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 that this is a parameterless tool with an output schema, the description sufficiently covers both what the tool does and when to use it. It explains its role in the workflow ('call this FIRST') without needing to detail output fields, which are available in the output schema. The content is complete for its complexity.

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 is 4. The description adds meaning by clarifying that the output is organized 'per type', though the exact return structure is presumably covered by the output schema. No parameter explanation is needed.

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 uses a specific metaphor ('Instant census') and explicitly states the resource ('entity count per type'). This clearly identifies the tool's function and distinguishes it from sibling query tools like get_extents or entity_length by positioning it as a first-step overview.

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 tells the agent to 'call this FIRST to understand a drawing', providing clear timing and priority guidance. The word 'cheap' adds a practical reason for this ordering. It does not mention exclusions or alternatives, but for a zero-parameter tool this is sufficient.

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