Boundary from Entities

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

The description adds valuable behavioral context beyond annotations: handles may arrive in any order, the tool orders them, refuses non-closing chains, and names gap coordinates. Since annotations only provide destructiveHint=false, this information significantly helps the agent understand error behavior.

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 concise and front-loaded, with two short paragraphs covering the core action and key behavioral notes. There is no redundant wording or filler.

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?

An output schema is present, reducing the need to explain return values. The description covers the main workflow, order-independence, and error behavior. It could specify which entity types are accepted (e.g., lines, arcs) but overall is sufficiently complete for the tool's 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?

The input schema already fully documents both parameters (handles and tolerance). The description adds a relevant note about handle ordering but does not elaborate on the tolerance parameter's semantics beyond the schema's built-in description.

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's function: 'Chain the given entities into one closed polyline.' The specific verb 'chain' and resource 'entities into one closed polyline' distinguish it from sibling tools like boundary_trace or entity_create_polyline.

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 implies the use case (entities forming a closed loop) but does not explicitly state when to use this tool over alternatives. It does not mention sibling tools or exclusion criteria, so usage context is only implicit.

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