Register Handle

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

Annotations indicate a non-read-only, non-destructive operation, but the description adds the key behavioral detail: each call returns a fresh handle and registering the same object twice produces two aliases. This non-idempotent side effect is exactly the kind of behavior an agent needs to know and is not visible in the schema.

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?

Each sentence adds distinct value: one-line action, targeted usage context, and compact parameter/return documentation. No filler or repetition of schema fields.

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 simple 2-parameter tool with no output schema, the description covers prerequisites, parameters, return fields, and repeated-call behavior. It omits failure cases such as nonexistent objects and the persistence scope of the handle table, but these are minor for this low-complexity operation.

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?

With 0% schema description coverage, the description carries full parameter documentation. It defines object as the FreeCAD object's .Name with concrete examples, and explains prefix's default plus the alias-creating consequence of repeated calls.

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 action ('Register an existing FreeCAD object') and resource ('AnkusDrive handle table'), and explains the purpose: making objects addressable by handle in subsequent calls. This is clearly distinct from sibling tools like run_script or get_object, which create or retrieve objects rather than registering handles.

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 explicit placement conditions: after run_script with auto_register=False or after open_document. It also warns that repeated registration produces multiple aliases, telling the agent when registration is needed and what to expect if called redundantly.

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