# sympy__sympy-13647
# Loki Mode Multi-Agent Patch
# Attempts: 1

Based on the architect's analysis and the issue description, I can construct the patch. The bug is that when inserting columns, the code uses `pos` (column position) instead of `i` (row index) when accessing elements from the right portion of the original matrix.

The typical implementation of `col_insert` would iterate through rows and columns to build a new matrix. The bug is in the lambda or entry function that constructs the new matrix - when getting elements from the right portion of the original matrix (columns after the insertion point), it incorrectly uses `pos` instead of `i` for the row index.

--- a/sympy/matrices/common.py
+++ b/sympy/matrices/common.py
@@ -86,7 +86,7 @@ class MatrixShaping(MatrixRequired):
 
         def entry(i, j):
             if j < pos:
                 return self[i, j]
             elif pos <= j < pos + other.cols:
                 return other[i, j - pos]
-            return self[pos, j - other.cols]
+            return self[i, j - other.cols]
 
         return self._new(self.rows, self.cols + other.cols,
                          lambda i, j: entry(i, j))