Sure! Below is a test case generator for the given "Circle" problem statement:

```python
import random
import math

def tcgen():
    # Generate a random radius r between 0 (exclusive) and 10000 (exclusive)
    r = random.uniform(0.00001, 9999.99999)
    
    # Calculate the area and circumference of the circle
    area = math.pi * r * r
    circumference = 2 * math.pi * r
    
    # Format the output to ensure precision up to 10^-5
    area = format(area, '.6f')
    circumference = format(circumference, '.6f')
    
    return r, area, circumference

# Example usage:
r, area, circumference = tcgen()
print(f"Radius: {r}")
print(f"Expected Output: {area} {circumference}")
```

This function generates a random radius `r` within the specified constraints, calculates the area and circumference of the circle, and formats the results to ensure that they do not contain an absolute error greater than \(10^{-5}\). The generated test cases can be used for testing solutions to the problem.

To generate multiple test cases or to integrate this into a larger testing framework, you can call `tcgen()` multiple times and collect the results.