bp_add_call_interface_function

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

With no annotations, the description must carry behavioral disclosure. It does disclose the core mutation ('Add a ... node'), that the returned node 'exposes the interface message pins', and the expected next step. However, it does not cover side effects on the graph, failure cases, or whether the operation is undoable or transactional.

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 one-line purpose, followed by compact usage guidance, an Args block, a KB pointer, and a complete example. Every sentence earns its place and no filler is present.

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 a small 4-parameter tool, the description includes enough to invoke it: purpose, each parameter, an example, and a pointer to connect pins with bp_connect_pins. With an output schema present, return-value documentation is not necessary; absence of error semantics and sibling differentiation leaves a small gap.

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 0%, and the Args block supplies the missing meaning: each parameter gets a type/role, including 'Optional [X, Y] graph position' and asset path semantics. Formats and defaults beyond node_position are not specified, but this is acceptable given the schema titles are uninformative.

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?

Description opens with 'Add a Blueprint Interface message-call node to a Blueprint graph', a specific verb+resource statement, and adds the loose-coupling rationale. It does not explicitly distinguish why this tool differs from sibling add_call_interface_function_node, so it stops short of a 5.

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?

States 'Use this when a graph should call an interface function on a target object without coupling to a concrete class' and gives a concrete follow-up action to connect pins with bp_connect_pins. It does not list exclusions or compare with sibling node-creation tools, so it fits 'clear context, no exclusions' rather than full routing guidance.

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