diff --git a/mapytex/calculus/core/typing/__init__.py b/mapytex/calculus/core/typing/__init__.py
index cd3eac4..1845502 100644
--- a/mapytex/calculus/core/typing/__init__.py
+++ b/mapytex/calculus/core/typing/__init__.py
@@ -37,6 +37,30 @@ def typing(node, left_v, right_v):
         raise TypingError(f"Unknown operation ({node})")
     return operation(left_v, right_v)
 
+def typing_capacities(node):
+    """ Test an operation through all MOs 
+
+    :param operation: string which represent an (mo, mo) -> mo
+    :returns: { (motype, motype): True/False } when it's implemented
+
+    :example:
+    >>> typing_capacities("+")
+    [['+', 'MOnumber', 'MOstr', 'MOFraction', 'MOstrPower', 'MOMonomial'], ['MOnumber', True, False, True, False, False], ['MOstr', False, False, False, False, False], ['MOFraction', True, False, True, False, False], ['MOstrPower', False, False, False, False, False], ['MOMonomial', False, False, False, False, False]]
+
+    """
+    op = OPERATIONS[node]
+    lines =  [[node] + [mo.__name__ for mo in MOS]]
+    for left_mo in MOS:
+       lines.append(
+           [left_mo.__name__] + \
+           [(left_mo, i) in op.funcs for i in MOS]
+       )
+    return lines
+
+typing.__doc__ += "Implemented typing operations among MOs"
+for op in OPERATIONS:
+    typing.__doc__ += f"\n{tabulate(typing_capacities(op), tablefmt='grid')} \n"
+
 
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