# `Monty.Frameworks.Environments.PositioningProcedures.ObjectNotVisibleError`
[🔗](https://github.com/d-led/ex.tbp.monty/blob/v0.1.0/packages/ex_tbp_monty_core/lib/monty/frameworks/positioning_procedures/object_not_visible_error.ex#L1)

Raised when a single-object scene shows no object to position against.

Mirrors
`tbp/monty/frameworks/environments/positioning_procedures.py::ObjectNotVisibleError`.
A multi-object scene treats "the target is not in view" as an answer — the
procedure declines to move and the episode starts from where it is — but a
single-object scene has nothing else to look at, so it is a fault in how the
episode was set up.

---

*Consult [api-reference.md](api-reference.md) for complete listing*