BoundaryML/baml · error

Enum {} not found

Error message

Enum {} not found

What it means

find_enum in ScopedIR fails when the requested enum name is absent from the IR and no RuntimeEnumOverride exists. Same resolution model as find_class: only a static BAML definition or a dynamic override satisfies the lookup.

Source

Thrown at engine/baml-runtime/src/internal/prompt_renderer/scoped_ir.rs:55

        let class = self.ir.find_class(class_name);

        match (class, class_override) {
            (Err(_), None) => Err(anyhow::anyhow!("Class {} not found", class_name)),
            (Ok(class), None) => Ok(FindResult::OnlyIr(class)),
            (Err(_), Some(class_override)) => Ok(FindResult::OnlyDynamic(class_override)),
            (Ok(class), Some(class_override)) => Ok(FindResult::Overriden(class, class_override)),
        }
    }

    fn find_enum(
        &self,
        enum_name: &str,
    ) -> Result<FindResult<internal_baml_core::ir::EnumWalker<'ir>, &RuntimeEnumOverride>> {
        let enum_override = self.ctx.enum_overrides.get(enum_name);
        let r#enum = self.ir.find_enum(enum_name);

        match (r#enum, enum_override) {
            (Err(_), None) => Err(anyhow::anyhow!("Enum {} not found", enum_name)),
            (Ok(r#enum), None) => Ok(FindResult::OnlyIr(r#enum)),
            (Err(_), Some(enum_override)) => Ok(FindResult::OnlyDynamic(enum_override)),
            (Ok(r#enum), Some(enum_override)) => Ok(FindResult::Overriden(r#enum, enum_override)),
        }
    }
}

impl IRSemanticStreamingHelper for ScopedIr<'_> {
    fn class_streaming_needed_fields(
        &self,
        class_name: &str,
    ) -> Result<std::collections::HashSet<String>> {
        let class_type = &self.find_class(class_name)?;
        let result = match class_type {
            FindResult::OnlyIr(cls) | FindResult::Overriden(cls, _) => cls
                .walk_fields()
                .filter_map(|field| {
                    if field.streaming_behavior().needed {

View on GitHub (pinned to bd85ce9dee)

Solutions

1. Declare the enum in a .baml file or correct the spelling of its name.
2. Provide a RuntimeEnumOverride in RuntimeContext.enum_overrides for dynamically defined enums.
3. Regenerate the BAML client so the IR includes recent schema changes.
4. Confirm the enum's file is included in the BAML source directory.

Example fix

// before (baml)
class Output {
  cat Catgory
}
// after
enum Category { A B }
class Output {
  cat Category
}

if scoped.find_enum(enum_name).is_err() {
    eprintln!("Enum {} missing from BAML schema", enum_name);
}

fn enum_resolves(scoped: &ScopedIr, name: &str) -> bool {
    scoped.find_enum(name).is_ok()
}

let ew = scoped.find_enum(enum_name)
    .with_context(|| format!("Check .baml files for enum {}", enum_name))?;

When it happens

Trigger: Prompt/output rendering resolves an enum type name that no .baml file declares and RuntimeContext has no enum_overrides entry for it.

Common situations: Misspelled enum name; enum renamed/removed; enum file outside baml_src; using dynamic schema overrides but forgetting to register the enum override.

Understand the failure class

Background: 'Could not be found', 'does not exist', 'not found in database': the resource-not-found family when an ID, slug, key, or URI lookup comes back empty — this error's family across 20 libraries.

Related errors

• Enum {} does not exist
• Class {} not found
• Enum with name {name} does not exist
• function `{function_name}` not found
• function `{target_name}` not found

AI-assisted analysis of BoundaryML/baml@bd85ce9dee (2026-09-12). Data as JSON: /api/errors/87a646459b09d5e3. Report an issue: GitHub.