At the far end of the Chirinos valley, where the forest closes in and the plots thin out, you reach the territory of the Apo people — around 3,000 individuals living in one of the more isolated communities in northern Peru. Many speak little or no Spanish. The community has had very limited contact with outsiders on any sustained basis, which means a visit needs to be approached with care and genuine respect for the fact that you are a guest in someone else's home, not a sight to be consumed.
The practical approach is to ask locally before entering — find the president of the local Ronda, the community organisation that handles most governance and social questions in this part of Peru, and explain your intentions. The Ronda presidents along the valley are generally the best point of contact for anything involving access, hospitality, or help of any kind. Be aware that this territory, like much of the surrounding forest, has been granted under concession to foreign mining interests, and the community has been actively resisting those concessions. The social movement around this issue is part of the fabric of daily life here, and it is worth knowing about before you arrive.