Your First Graph
This walkthrough builds a tiny pipeline that feeds an explicit tensor through a couple of operations — enough to learn the Start node execution model that every CodefyUI graph relies on.
1. Add an input
Drag a TensorInput node (Data category) onto the canvas. Set its value_mode to explicit and fill the inline grid editor with the numbers you want the pipeline to see.
2. Wire up some operations
Connect it through any chain of tensor-op nodes, for example:
TensorInput → Reshape → Softmax → Print
Drag from each output port to the next input port. The edges validate types as you connect.
3. Add a Start node
:::warning Every graph needs a Start node
Drag a Start node onto the canvas and connect its trigger output (the diamond handle on the right side) to the first node you want executed — typically the TensorInput.
Without a Start → first-node trigger edge, the graph is treated as a draft and Run rejects it with a "No start node defined" toast. Only nodes reachable from a Start are executed.
:::
This trigger-based routing is what lets you keep scratch nodes on the canvas without running them, and it enables conditional branches (e.g. a Switch node) where only one path executes.
4. Run it
Click Run. Watch per-node progress stream into the Execution Log, and the Print node's output appear there too. See Running Graphs for what happens during execution.
5. Inspect what flowed
Open the Settings popover, switch Record outputs ON, and run again. Now click any node to open the Teaching Inspector and see the exact tensor — shape, dtype, min/max/mean, and values — at every step.
Next steps
- Load a real example instead of building from scratch — see the Examples Gallery (e.g. Train CNN on MNIST).
- Browse every node you can drop on the canvas in the Node Reference.