According to Section 10 SGB II (Social Security Code II) Paragraph 1, the law stipulates that you must take up any job that reduces or ends your need for assistance (benefit receipt). This includes working for a temporary employment agency as well as a mini-job.
Any work is therefore reasonable for a person who is capable of working and entitled to benefits, unless
1. they are physically, mentally, or emotionally incapable of performing the specific work,
2. performing the work would make it significantly more difficult to continue performing their previous main job, because their previous job involved particular physical demands,
3. performing the work would jeopardize the upbringing of her child or her partner's child [...],
4. performing the work would be incompatible with caring for a relative and the care cannot be provided in any other way, or there is another important reason preventing the performance of the work.