assemble

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

With no annotations, the description carries the full burden and does an excellent job. It discloses that this is a single transaction, that per-mate residuals are measured AFTER the move, that a mate over tolerance fails, and that stop_on_error aborts and rolls back. It also states the return format, giving the agent a clear picture of side effects and behaviors.

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 well-structured with clear sections for behavior, arguments, and returns. It is front-loaded with the core purpose, and every sentence adds value. The pointer to operation_help keeps it concise without sacrificing completeness.

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 the complexity of the assembly operation and the bare schema, the description is quite complete: it explains the mate format, failure behavior, rollback, and return values. However, it misses the required doc_name parameter and does not elaborate on the differences between center/touch/axis modes, though it defers to operation_help for full semantics.

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 description adds significant meaning beyond the schema by detailing the structure of each mate dict, including the mode enum and default offset. However, it entirely omits the required doc_name parameter from the Args list, and since schema coverage is 0%, this is a notable gap that prevents a higher score.

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 clearly states the tool assembles parts by snapping named anchors together, with a specific verb and resource. It also distinguishes itself from the sibling tool assembly_session by noting that assembly_session is for PERSISTENT joints, and it emphasizes the ONE transaction behavior.

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 says 'For PERSISTENT joints use assembly_session', providing a clear alternative. It also points to operation_help for full semantics, but it does not fully elaborate on when to use assemble vs other assembly-related sibling tools like align_shapes or verify_assembly.

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