cad_block

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

Annotations already declare destructiveHint=true, readOnlyHint=false, and idempotentHint=false, so the safety profile is established. The description adds useful input context ('from entities' and 'import a DWG as a block') but does not disclose side effects such as overwriting an existing block definition, deleteSource behavior, or zoomToResult effects. With annotations carrying the destructive/mutation burden, this is adequate but not rich.

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 one sentence and front-loads the core operations, making it easy to scan. It earns its place by naming four relevant actions. It is not bloated, though the ambiguity around 'redefine it' slightly reduces clarity.

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?

For a tool with 15 parameters, nested objects, multiple actions, no output schema, and only 20% schema description coverage, the description is far too thin. It omits action-parameter relationships, required expectedDocumentId/expectedRevision concurrency semantics, result conventions, and side-effect details, so an agent cannot confidently invoke all advertised operations 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?

Schema description coverage is only 20%, and the description does not compensate. It fails to explain how action maps to the other 15 parameters, such as sourceHandles for create, sourcePath for import, or insertionPoint/scale/rotation for insert. The 'redefine' phrase is also not represented in the action enum, creating possible parameter-selection ambiguity.

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 specific block-domain verbs and a clear resource: 'Create a block definition from entities, insert a block, redefine it, or import a DWG as a block.' It is clearly about block operations and distinguishes this tool from the other cad_* siblings by resource and action. It stops short of 5 because it mentions 'redefine it' while the schema action enum only lists create, insert, and import.

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 guidance is given about when to use this tool versus alternatives such as cad_draw, cad_edit, or cad_command. There are no exclusions, prerequisites, or context cues beyond listing the actions. The agent is left to infer the appropriate use case from the action names alone.

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