constrain

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

Without annotations, the description carries full behavioral disclosure. It mentions that origin constraints survive part edits (a durability trait) but omits key mutation details: permissions required, whether the operation is reversible, what happens on constraint conflict, or whether the assembly is modified in place. This is insufficient for a mutation tool with zero annotation coverage.

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 front-loaded with the main purpose and then lists arguments in a clear, structured format. The first sentence efficiently conveys the core value proposition, and the bullet list is easy to scan. No unnecessary fluff, though the first sentence is slightly verbose.

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 (8 parameters, assembly operation) and the presence of an output schema, the description covers the essential information for calling the tool: purpose, parameter meanings, and allowed values. It lacks some behavioral details like failure modes or prerequisites, but these are partly mitigated by the output schema and inferred context.

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 13% (only 'instance' has a description). The description compensates by explaining most parameters: occurrence indices with a pointer to list_occurrences, allowed values for geometry1/geometry2, semantics of kind (mate/flush/angle), and units for offset and angle. Only 'instance' (covered in schema) lacks additional detail.

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 states a specific verb (constrain) and resource (two components by ORIGIN geometry), and explicitly differentiates from face-based constraints by explaining why origin constraints are more robust. An agent can immediately tell this is for origin geometry, not face picks.

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 provides clear context for when to use this tool (origin constraints survive edits) but does not explicitly name alternatives or when-not-to-use conditions. The contrast with face picks is implied but not framed as an explicit alternative.

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