add_get_spline_length_node

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

No annotations are present, so the description must carry behavioral disclosure itself. It clearly signals a graph mutation via 'Add', and the node_position arg plus example indicate placement in a Blueprint graph. It does not state whether the graph is saved/compiled or what the node's output pins are, though the output schema mitigates the latter.

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 organized into purpose, usage context, Args, KB link, and example, with the core purpose front-loaded. It is compact relative to the number of parameters and contains no filler. The Ch. 19 and KB references are lightweight extras that add context without bloating the definition.

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?

All parameters are semantically covered, a concrete example is provided, and an output schema exists to document return values. The only missing piece is a direct mention of the graph context where the node is added, which is largely implicit from the node_position argument and the overall add-node tool family.

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 schema has 0% description coverage, but the Args block describes all three parameters: blueprint_name as the Blueprint containing the Spline, spline_component_variable as the Spline reference name, and node_position as [X, Y] graph position. This compensates for the empty schema descriptions and adds meaning beyond the raw schema fields.

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 first sentence names a specific verb (Add), a concrete resource (GetSplineLength node), and the result (total length of a Spline). This clearly distinguishes it from sibling node-adders such as add_get_location_at_distance_along_spline_node and add_get_rotation_at_distance_along_spline_node.

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?

It grounds usage in a concrete scenario: the CalculateNumberOfInstances macro determines how many instances fit along the spline at a given spacing. This gives clear context without explicitly listing exclusions or alternatives. The context is sufficient for an agent to infer when this node is appropriate.

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