Source code for protomotions.agents.base_agent.model

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"""Base model interface for agent neural networks.

This module defines the abstract base class that all agent models must implement.
It provides a TensorDictModule interface for clean, compilable models.

Key Classes:
    - BaseModel: Abstract base class for all agent models (TensorDictModule)
"""

from tensordict import TensorDict
from tensordict.nn import TensorDictModuleBase
from protomotions.agents.base_agent.config import BaseModelConfig
from abc import abstractmethod




class BaseModel(TensorDictModuleBase):
    """Base class for all agent models.

    All models are TensorDictModules with a single forward method that
    processes observations and returns all model outputs in a TensorDict.

    Args:
        config: Model configuration with architecture parameters.

    Attributes:
        config: Stored configuration for the model.
        in_keys: Input keys for TensorDict (set by subclasses).
        out_keys: Output keys for TensorDict (default: ["action"]).
    """



    def __init__(self, config: BaseModelConfig):
        super().__init__()
        self.config = config

        # Default output keys (subclasses can override)
        self.out_keys = ["action"]
        # in_keys will be set by subclasses based on their architecture
        self.in_keys = []




    @abstractmethod
    def forward(self, tensordict: TensorDict) -> TensorDict:
        """Forward pass through the model.

        Args:
            tensordict: TensorDict containing observations.

        Returns:
            TensorDict with model outputs added.
        """
        pass