By default this hook will stop any commits that includes the string 'TODO'. If you have added a TODO it is better to register it on a purpose built issue tracking system. This default however may not be to everyone's taste. You can turn this off by adding the following configuration:
git config hooks.excluded-strings.disabled true
Or you can specify a file which includes a new-line separated list of strings that should not be allowed in your commits.
git config hooks.excluded-strings.file exclusions.text
You can also customise the error message.
git config hooks.excluded-strings.message "Your message here"
The line that cannot be committed will be printed immediately after your message on the same line.