[BUG] Example 01: hardcoded ❌ icon conflicts with validator returning Valid: True

[echo-xiao]

Describe the bug
In examples/01_forecasting_workflow.py, Step 5 shows a hardcoded ❌ icon for the pipeline ['NaiveForecaster', 'ExponentialSmoothing'], but the validator returns Valid: True. The code comment says # Invalid pipeline: Forecaster -> Forecaster, suggesting two forecasters in series should be invalid — but the validator does not detect this as an error.

To Reproduce
python examples/01_forecasting_workflow.py

Output in Step 5:
❌ Testing: ['NaiveForecaster', 'ExponentialSmoothing']
Valid: True

Expected behavior
Either:

1. The validator should return Valid: False with an error explaining that two forecasters cannot be chained, or
2. If the pipeline is actually valid, the ❌ icon and the comment # Invalid pipeline should be corrected to ✅

Additional context
The relevant code is in examples/01_forecasting_workflow.py line 114:

Invalid pipeline: Forecaster -> Forecaster

print("\n❌ Testing: ['NaiveForecaster', 'ExponentialSmoothing']")
result = validator.validate_pipeline(["NaiveForecaster", "ExponentialSmoothing"])
print(f" Valid: {result.valid}")

Versions

Details

System:
python: 3.13.11
machine: macOS-26.3-arm64-arm-64bit-Mach-O

Python dependencies:
sktime: 0.40.1
sklearn: 1.7.2
numpy: 2.3.5
scipy: 1.17.1
pandas: 2.3.3
pmdarima: 2.1.1
statsmodels: 0.14.6
sktime-mcp: 0.1.0

[Agrim-Dubey]

can i work on this if its free ?

[echo-xiao]

@Agrim-Dubey Yes, it's free! Feel free to work on it 😊

[SHRISHTI1414]

Hi! I'd like to work on this. I'll open a PR shortly with the fix.