Axon documentation

Understand the model,
not just the output.

A guided manual for training, debugging, comparing, and exporting small neural networks in Axon Studio.

Onboarding

Getting Started

Axon Studio is a browser-based neural-network lab for small 2D classification problems. It is built to show how a model learns, not just what it predicts at the end.

  • Train directly in the browser with TensorFlow.js
  • Watch the decision field update epoch by epoch
  • Inspect errors, confidence, weights, and saved snapshots

First run

Quick Start

Open the playground, select a preset, press Run, then switch between boundary, errors, and gradients. Pause training and scrub the epoch timeline to inspect earlier states.

  • Use Space to run or pause
  • Use S to step one epoch
  • Use E / G / B to switch view modes

Datasets

Choosing a Dataset

Axon ships with four built-in datasets and supports custom CSV import. Pick a dataset based on the learning behavior you want to observe.

  • XOR — classic non-linear split; requires hidden layers
  • Circles — fast convergence; great for boundary demos
  • Spiral — stress test; reveals limits of small networks
  • Blobs — linearly separable; sanity-check baseline

Step by step

Training Your First Model

Select the Circles clean preset, leave all defaults, and press Run. The decision boundary will start forming within the first few epochs. Use the epoch timeline to scrub back and see how the boundary evolved.

  • Step 1 — Select a preset from the left panel
  • Step 2 — Press Run or hit Space
  • Step 3 — Watch the boundary form in the center canvas
  • Step 4 — Pause and scrub the timeline to inspect earlier epochs

Power user

Keyboard Shortcuts

All major playground actions are accessible from the keyboard. These shortcuts work as long as focus is not inside a text input.

  • Space — run / pause training
  • R — reset model and data
  • S — step one epoch
  • E — switch to Errors view
  • G — switch to Gradients view
  • B — switch to Boundary view
  • Ctrl / Cmd + S — save current run

Visual model output

Decision Boundary

The central square maps the x₁ / x₂ input space. Purple and pink regions show the predicted class, while the contour line shows the 0.5 decision threshold.

  • Darker regions indicate stronger model confidence
  • The contour line marks where the model changes class
  • Train/test points show whether the boundary generalizes

Debugging mistakes

Misclassification Lens

Errors view highlights points where the predicted label does not match the true label. This helps you understand whether the model is underfitting, overfitting, or confused by noisy data.

  • Orange rings mark visible errors on the canvas
  • The right panel shows the total misclassified count
  • Click any point to inspect its prediction path

Point-level transparency

Forward-Pass Inspector

Click any data point on the boundary canvas to inspect how that specific input travels through the network layer by layer. The right panel shows activations, output score, and confidence.

  • Shows layer-by-layer activation values
  • Displays predicted class and probability
  • Works on both training and test points

Generalization

Train / Test Split

Axon reports train accuracy, test accuracy, and generalization gap. This stops the playground from becoming a pure memorization demo.

  • Train accuracy measures fitted points
  • Test accuracy uses held-out examples
  • A large gap means the model may not generalize

Layer-level learning

Gradient Flow

The Gradients view and layer flow indicators show how strongly each layer is updating. Use this to detect vanishing gradients or stuck layers.

  • Bright layers are updating strongly
  • Dim layers may have vanishing gradients
  • Switch to Gradients view with the G shortcut

Custom datasets

CSV Format

CSV mode supports two numeric input columns and one binary label column. Axon normalizes x/y values to [-1, 1] so the dataset fits the boundary canvas.

  • Expected columns: x, y, label
  • Labels can be 0/1 or two distinct class names
  • Invalid rows are counted and excluded before training

Auto-parsing

Column Detection

When you upload a CSV, Axon scans the header row and attempts to auto-detect which columns are numeric inputs and which is the binary label. You can override the selection manually.

  • Numeric columns are auto-selected as x and y inputs
  • The label column is inferred from binary-valued data
  • Manual override is available if detection is wrong

Error handling

Validation States

The CSV importer validates each row before training. Rows with non-numeric values, missing fields, or out-of-range labels are flagged and excluded.

  • Invalid row count is shown before training starts
  • At least 20 valid rows are required to proceed
  • Validation errors are shown inline in the importer

Data preprocessing

Normalization

All input features are normalized to [-1, 1] based on the min/max of the uploaded dataset. This ensures the values fit the boundary canvas and the model trains stably.

  • Min/max normalization applied per column
  • Normalization is automatic and cannot be disabled
  • Original values are preserved in the export JSON

Data quality

Invalid Rows

Rows that fail validation are silently excluded from training. The importer shows a count of invalid rows so you can assess data quality before proceeding.

  • Rows with non-numeric inputs are excluded
  • Rows with labels outside the detected class set are excluded
  • Completely empty rows are ignored

Experiment tracking

Compare Runs

Save multiple runs from the playground and compare them on the Experiments page. Each saved run stores the architecture, dataset, metrics, and training config.

  • Save a run with Ctrl/Cmd+S or the save run button
  • Up to 8 runs are stored in localStorage
  • Compare accuracy, loss, and architecture side by side

Portable results

Export JSON

Export a full experiment snapshot as JSON. The file includes metrics, architecture config, dataset metadata, snapshots, and saved runs.

  • Includes train/test accuracy and loss
  • Captures the full layer configuration
  • Useful for logging results outside the browser

Visual export

Export Boundary PNG

Download a screenshot of the current decision boundary canvas as a PNG. The export captures the exact visual state including points, boundary regions, and confidence zones.

  • Exports at canvas resolution
  • Captures the currently active view mode
  • Useful for presentations and reports

Quick share

Copy Experiment Summary

Copy a human-readable text summary of the current experiment to your clipboard. The summary includes dataset, architecture, epoch count, loss, and accuracy.

  • Paste into a notebook, README, or issue
  • Includes all key metrics in plain text
  • Generated from the current visible state

Run history

Saved Experiments

The Experiments page shows all runs you have saved from the playground. Runs are stored in localStorage and persist across page refreshes.

  • Access saved runs from the top navigation
  • Delete individual runs or clear all at once
  • Export all runs as a single JSON file