xai-org/x-algorithm · error · ValueError

No task generator registered for type {cfg.type!r}. Register

Error message

No task generator registered for type {cfg.type!r}. Registered: {sorted(_REGISTRY)}

What it means

build(cfg) resolves a TaskGeneratorConfig to a registered class via cfg.type. If no class was registered under that type string, there is no way to construct the generator, so it raises ValueError listing all registered types to aid diagnosis.

Source

Thrown at grox/core/generators/registry.py:29

        )
    if not cls.TASK_GENERATOR_TYPE:
        raise ValueError(
            f"{cls.__name__} must set TASK_GENERATOR_TYPE to be registered"
        )
    key = cls.TASK_GENERATOR_TYPE
    existing = _REGISTRY.get(key)
    if existing is not None and existing is not cls:
        raise ValueError(
            f"Duplicate generator registration for {key!r}: {existing.__name__} vs {cls.__name__}"
        )
    _REGISTRY[key] = cls
    return cls


def build(cfg: TaskGeneratorConfig) -> TaskGenerator:
    cls = _REGISTRY.get(cfg.type)
    if cls is None:
        raise ValueError(
            f"No task generator registered for type {cfg.type!r}. Registered: {sorted(_REGISTRY)}"
        )
    return cls.from_config(cfg)


def registered_types() -> set[str]:
    return set(_REGISTRY)

View on GitHub (pinned to 24c60942c5)

Solutions

1. Import the module that defines (and decorates) the generator before calling build so registration happens.
2. Fix the type string in the config to exactly match TASK_GENERATOR_TYPE (the error message lists valid values).
3. Ensure the value's case/whitespace matches — no stripping is done.
4. If the generator lives in a plugin package, verify the package is installed and its import side effects run.

Example fix

# before
cfg = TaskGeneratorConfig(type="task_gen")
gen = build(cfg)  # registry has "task_generator"

# after
import mypkg.generators.my_gen  # triggers @register_task_generator
cfg = TaskGeneratorConfig(type="my_gen")
gen = build(cfg)

from grox.core.generators.registry import registered_types

if cfg.type not in registered_types():
    raise ValueError(f"unknown generator {cfg.type}; known: {registered_types()}")
import mypkg.generators  # ensure registrations ran

def config_type_is_registered(cfg) -> bool:
    from grox.core.generators.registry import registered_types
    return cfg.type in registered_types()

try:
    gen = build(cfg)
except ValueError as e:
    if "No task generator registered" in str(e):
        import mypkg.generators  # late import to register
        gen = build(cfg)
    else:
        raise

When it happens

Trigger: Calling registry.build with a TaskGeneratorConfig whose type string doesn't match any registered TASK_GENERATOR_TYPE; typo in config; generator module never imported (so its @register_task_generator never ran).

Common situations: Config file references a generator from a module that isn't imported/installed; renaming a generator's type without updating configs; typos or casing mismatches in the type string; plugin module not loaded in the entry point.

Related errors

• {cls.__name__} must set TASK_GENERATOR_TYPE to be registered
• Duplicate generator registration for {key!r}: {existing.__na
• head registry hash {head_cfg.get('head_registry_hash')} != {
• register_task_generator expects a TaskGenerator subclass, go
• No generators provided

AI-assisted analysis of xai-org/x-algorithm@24c60942c5 (2026-08-28). Data as JSON: /api/errors/b1f775a4f3ac898f. Report an issue: GitHub.