run-llama/llama_index · error · ValueError

Playground must have a non-empty list of indices.

Error message

Playground must have a non-empty list of indices.

What it means

Error "Playground must have a non-empty list of indices." thrown in run-llama/llama_index.

Source

Thrown at llama-index-core/llama_index/core/playground/base.py:87

        Args:
            documents: A List of Documents to experiment with.

        """
        if len(documents) == 0:
            raise ValueError(
                "Playground must be initialized with a nonempty list of Documents."
            )

        indices = [
            index_class.from_documents(documents, **kwargs)
            for index_class in index_classes
        ]
        return cls(indices, retriever_modes)

    def _validate_indices(self, indices: List[BaseIndex]) -> None:
        """Validate a list of indices."""
        if len(indices) == 0:
            raise ValueError("Playground must have a non-empty list of indices.")
        for index in indices:
            if not isinstance(index, BaseIndex):
                raise ValueError(
                    "Every index in Playground should be an instance of BaseIndex."
                )

    @property
    def indices(self) -> List[BaseIndex]:
        """Get Playground's indices."""
        return self._indices

    @indices.setter
    def indices(self, indices: List[BaseIndex]) -> None:
        """Set Playground's indices."""
        self._validate_indices(indices)
        self._indices = indices

    def _validate_modes(self, retriever_modes: INDEX_SPECIFIC_QUERY_MODES_TYPE) -> None:

View on GitHub (pinned to afd0fef371)

Solutions

1. Pass at least one index to Playground, or let it build default indices from the documents.
2. Remove the empty indices list and allow indices to be built from documents.

When it happens

Trigger: Thrown at llama-index-core/llama_index/core/playground/base.py:87 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of run-llama/llama_index@afd0fef371 (2026-08-15). Data as JSON: /api/errors/934d1c46877ce4af. Report an issue: GitHub.