zylon-ai/private-gpt · error · ValueError

Unknown condense strategy: {strategy}

Error message

Unknown condense strategy: {strategy}

What it means

ValueError from get_condense_memory_strategy (base_strategy.py). The factory resolves the strategy string to a CondenseStrategyType enum (via from_string) or accepts an enum directly, then looks it up in _PROVIDERS; only strategies registered through register_condense_strategy exist (built-in example: "condenser"). An unresolvable name yields this error.

Source

Thrown at private_gpt/components/chat/processors/chat_history/memory/strategies/base_strategy.py:104

) -> BaseMemoryStrategy:
    """Get the condense strategy from a string or CondenseStrategy enum.

    Args:
        strategy (str | CondenseStrategy): The strategy to get.
        injector (Injector | None): Optional dependency injector for workflow builders.
        **kwargs: Additional keyword arguments to pass to the strategy constructor.

    Returns:
        CondenseStrategy: The corresponding CondenseStrategy enum.
    """
    strategy_enum = (
        strategy
        if isinstance(strategy, CondenseStrategyType)
        else CondenseStrategyType.from_string(strategy)
    )
    provider = _PROVIDERS.get(strategy_enum)
    if provider is None:
        raise ValueError(f"Unknown condense strategy: {strategy}")
    return provider(injector=injector, **kwargs)

View on GitHub (pinned to 4a030776a3)

Solutions

1. Use a registered strategy name — check _PROVIDERS / the CondenseStrategyType enum for valid values (e.g. "condenser").
2. For custom strategies, call register_condense_strategy(...) with the name before get_condense_memory_strategy runs.
3. Fix casing/typos in the configured string; from_string matching is exact after normalization.
4. If a strategy disappeared after upgrade, check the changelog for its renamed replacement.

Example fix

// before
memory:
  condense:
    strategy: summary   # ValueError: Unknown condense strategy

// after
memory:
  condense:
    strategy: condenser

from private_gpt.components.chat.processors.chat_history.memory.strategies.base_strategy import _PROVIDERS

if strategy_name not in {s.value for s in _PROVIDERS}:
    raise ValueError(f"strategy must be one of {sorted(s.value for s in _PROVIDERS)}, got {strategy_name!r}")

def is_known_strategy(name: str) -> bool:
    from ...base_strategy import _PROVIDERS
    from ...base_strategy import CondenseStrategyType
    try:
        CondenseStrategyType.from_string(name)
        return True
    except Exception:
        return False

try:
    strategy = get_condense_memory_strategy(name, injector)
except ValueError as e:
    raise ValueError(f"Bad condense config: {e}. Available: condenser") from e

When it happens

Trigger: Configuring condense strategy settings with a typo or unregistered name (e.g. "summary", "rolling", "Condenser"); passing a custom strategy string without first calling register_condense_strategy; version drift where a renamed strategy no longer exists.

Common situations: settings.yaml condense blocks copied from other projects; upgrading private-gpt and strategy names changed; custom plugins whose registration runs after settings parsing.

Related errors

• Unknown memory type: {type}
• Token limit must be set and greater than 0.
• start_on can only be used with 'last' strategy
• include_system can only be used with 'last' strategy
• Invalid system item in list: {item}

AI-assisted analysis of zylon-ai/private-gpt@4a030776a3 (2026-08-15). Data as JSON: /api/errors/8659c37980aa6fa6. Report an issue: GitHub.