bevyengine/bevy · error · EntityNotSpawnedError

Entity not yet spawned: {0} Note that interacting with a not

Error message

Entity not yet spawned: {0}
Note that interacting with a not-yet-spawned entity is the most common cause of this error but there are others

What it means

Label message for the not-yet-spawned flavor of entity errors: the id is reserved/valid but its index has never been given a location in this World (e.g. an Entity obtained from reserve_entity or commands before the spawn is flushed). The note warns that any interaction with such an unspawned index, not only spawn misuse, produces this error.

Source

Thrown at crates/bevy_ecs/src/entity/mod.rs:1166

        match self.location.into_option() {
            Some(location) => write!(f, "The entity with ID {entity} is not spawned; its index was last despawned by {location}."),
            None => write!(
                f,
                "The entity with ID {entity} is not spawned; enable `track_location` feature for more details."
            ),
        }
    }
}

/// An error that occurs when a specified [`Entity`] is expected to be valid and spawned but is not.
/// Represents an error of either [`InvalidEntityError`] (when the entity is invalid) or [`EntityValidButNotSpawnedError`] (when the [`EntityGeneration`] is correct but the [`EntityIndex`] is not spawned).
#[derive(thiserror::Error, Copy, Clone, Debug, Eq, PartialEq)]
pub enum EntityNotSpawnedError {
    /// The entity was invalid.
    #[error("Entity despawned: {0}\nNote that interacting with a despawned entity is the most common cause of this error but there are others")]
    Invalid(#[from] InvalidEntityError),
    /// The entity was valid but was not spawned.
    #[error("Entity not yet spawned: {0}\nNote that interacting with a not-yet-spawned entity is the most common cause of this error but there are others")]
    ValidButNotSpawned(#[from] EntityValidButNotSpawnedError),
}

impl EntityNotSpawnedError {
    /// The entity that did not exist or was not spawned.
    pub fn entity(&self) -> Entity {
        match self {
            EntityNotSpawnedError::Invalid(err) => err.entity,
            EntityNotSpawnedError::ValidButNotSpawned(err) => err.entity,
        }
    }
}

#[derive(Copy, Clone, Debug)]
struct EntityMeta {
    /// The current [`EntityGeneration`] of the [`EntityIndex`].
    generation: EntityGeneration,
    /// The current location of the [`EntityIndex`].

View on GitHub (pinned to 396ca72708)

Solutions

1. Ensure spawn commands are flushed (or use world.flush_commands) before touching reserved entities
2. Pass reserved Entity ids only where spawning will complete, such as spawn_with commands
3. Re-query the entity after the frame's command flush to confirm it is live

When it happens

Trigger: Thrown at crates/bevy_ecs/src/entity/mod.rs:1166 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of bevyengine/bevy@396ca72708 (2026-08-20). Data as JSON: /api/errors/5f083cc966393d4b. Report an issue: GitHub.