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

With no annotations, the description carries the full burden. It discloses that the block is 'reusable' and that attributes are optional, but says nothing about side effects on the current drawing, duplicate-name behavior, persistence, or permissions. For a definition-creating mutation this is a notable gap.

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?

A single well-formed sentence with the core verb front-loaded and zero redundancy. It is efficient, though its brevity leaves the tool under-specified rather than over-explained.

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?

The tool has 4 parameters including nested objects, no annotations, and no output schema, yet the description never addresses basePoint semantics, expected entity object shape, error behavior, or what happens to the created block. Too thin for this 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?

Schema description coverage is 100%, so name, entities, basePoint, and attributes are already documented structurally. The description only restates that attributes are optional ATTDEFs, adding essentially no syntax or format detail beyond the schema, which is the expected baseline here.

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 and resource ('Defines a reusable Block') plus the payload it accepts (geometric entities, optional ATTDEF). It does not explicitly distinguish itself from the sibling cad_insert_block, so an agent must infer that this creates a definition rather than placing an instance.

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?

No when-to-use guidance, no prerequisites (e.g. must a drawing be open first), and no reference to cad_insert_block as the follow-up alternative. The agent gets the purpose but nothing about context of invocation.

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