Determines whether one ComfyUI node's output can connect to another node's input by checking node compatibility data, helping prevent invalid workflow links before execution.
Check if output of one node can connect to input of another (using node-compatibility.json).
| Name | Required | Description | Default |
|---|---|---|---|
| to_node | Yes | Target node class name | |
| from_node | Yes | Source node class name |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. The wording 'Check if' strongly implies a read-only lookup against node-compatibility.json, but it does not describe the return value, possible error cases, or whether any side effects occur.
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 a single compact sentence that states the operation and the compatibility source. There is no wasted text, and the core purpose is front-loaded.
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?
The tool is simple and the schema is fully documented, but there is no output schema and the description does not explain what the check returns or how failures are represented. That leaves a meaningful gap for an agent invoking the tool.
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 100%, so both parameters are already documented as source and target node class names. The description adds a little directionality by saying 'output of one node' to 'input of another,' but it does not expand parameter semantics beyond the schema.
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 gives a specific verb and resource: check whether one node's output can connect to another node's input. It is clear enough to distinguish from sibling tools like connect_nodes, though it does not explicitly name those alternatives.
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?
Usage is implied: use this before making a connection to see if it is valid. However, the description does not explicitly say when to use it instead of connect_nodes, validate_workflow, or get_node_inputs/get_node_outputs.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.