bevyengine/bevy · error · MissingProcessedAssetReaderError

Asset Source '{0}' does not have a processed AssetReader.

Error message

Asset Source '{0}' does not have a processed AssetReader.

What it means

MissingProcessedAssetReaderError: code requested the processed AssetReader for an asset source, but that source has no processed reader configured (no processing pipeline set up for it). Reading processed assets from this source cannot proceed.

Source

Thrown at crates/bevy_asset/src/io/source.rs:662

        for source in self.iter_processed_mut() {
            source.gate_on_processor(processing_state.clone());
        }
    }
}

/// An error returned when an [`AssetSource`] does not exist for a given id.
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[error("Asset Source '{0}' does not exist")]
pub struct MissingAssetSourceError(AssetSourceId<'static>);

/// An error returned when an [`AssetWriter`](crate::io::AssetWriter) does not exist for a given id.
#[derive(Error, Debug, Clone)]
#[error("Asset Source '{0}' does not have an AssetWriter.")]
pub struct MissingAssetWriterError(AssetSourceId<'static>);

/// An error returned when a processed [`AssetReader`](crate::io::AssetReader) does not exist for a given id.
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[error("Asset Source '{0}' does not have a processed AssetReader.")]
pub struct MissingProcessedAssetReaderError(AssetSourceId<'static>);

/// An error returned when a processed [`AssetWriter`](crate::io::AssetWriter) does not exist for a given id.
#[derive(Error, Debug, Clone)]
#[error("Asset Source '{0}' does not have a processed AssetWriter.")]
pub struct MissingProcessedAssetWriterError(AssetSourceId<'static>);

const MISSING_DEFAULT_SOURCE: &str =
    "A default AssetSource is required. Add one to `AssetSourceBuilders`";

View on GitHub (pinned to 396ca72708)

Solutions

1. Configure a processed reader (with_processed_reader) for the asset source
2. Run the AssetProcessor so processed outputs are produced and wired
3. Read from the unprocessed source instead if processing is not used

When it happens

Trigger: Thrown at crates/bevy_asset/src/io/source.rs:662 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/d703d6d278d6f2ed. Report an issue: GitHub.