mem0ai/mem0 · error · ValueError

Extra fields not allowed: {', '.join(extra_fields)}. Please

Error message

Extra fields not allowed: {', '.join(extra_fields)}. Please provide only the following fields: {', '.join(allowed_fields)}.

What it means

Error "Extra fields not allowed: {', '.join(extra_fields)}. Please provide only the following fields: {', '.join(allowed_fields)}." thrown in mem0ai/mem0.

Source

Thrown at mem0/configs/vector_stores/mongodb.py:21

from pydantic import BaseModel, ConfigDict, Field, model_validator


class MongoDBConfig(BaseModel):
    """Configuration for MongoDB vector database."""

    db_name: str = Field("mem0_db", description="Name of the MongoDB database")
    collection_name: str = Field("mem0", description="Name of the MongoDB collection")
    embedding_model_dims: Optional[int] = Field(1536, description="Dimensions of the embedding vectors")
    mongo_uri: str = Field("mongodb://localhost:27017", description="MongoDB URI. Default is mongodb://localhost:27017")

    @model_validator(mode="before")
    @classmethod
    def validate_extra_fields(cls, values: Dict[str, Any]) -> Dict[str, Any]:
        allowed_fields = set(cls.model_fields.keys())
        input_fields = set(values.keys())
        extra_fields = input_fields - allowed_fields
        if extra_fields:
            raise ValueError(
                f"Extra fields not allowed: {', '.join(extra_fields)}. "
                f"Please provide only the following fields: {', '.join(allowed_fields)}."
            )
        return values

    model_config = ConfigDict(arbitrary_types_allowed=False)

View on GitHub (pinned to 001c235229)

Solutions

1. Remove the extra config fields listed and keep only the allowed MongoDB fields (db_name, collection_name, user, password, host, port).

When it happens

Trigger: Thrown at mem0/configs/vector_stores/mongodb.py:21 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of mem0ai/mem0@001c235229 (2026-08-15). Data as JSON: /api/errors/570c954447c55f2b. Report an issue: GitHub.