Wrote documentation for id function in contract Foo.

src/Foo.sol

@@ -2,6 +2,16 @@
 pragma solidity >=0.8.23;
 
 contract Foo {
+  /**
+   * @notice This returns the value that it is given.
+   * @dev The current dev does not yet know what the permissible range of the
+   * uint256 values may be, nor how this function handles a None/void/null
+   * input if those exist in Solidity. Nor do I know how it handles with an
+   * overflow input value, if that is possible.
+   * @param value An integer that is assumed to be stored in a 256 bit memory.
+   * @return The value that it receives as input. The developer does not yet
+   * know whether Solidity passes uint256 variables by value or by reference.
+   */
   function id(uint256 value) external pure returns (uint256) {
     return value;
   }