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Common ModelOptions for Backend Generation.

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Classes

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CLASS ModelOption

A type that wraps around model options. Uses sentinel values (wrapped by @@@) to provide backend and model-agnostic keys for common model options. Create a dictionary containing model options like this: 
from mellea.backends import ModelOption
model_options = {{
    ModelOption.TEMPERATURE : 0.0,
    ModelOption.SYSTEM_PROMPT : "You are a helpful assistant"
}}
Attributes:
  • TOOLS: Sentinel key for a list or dict of tools to expose for tool calling.
  • MAX_NEW_TOKENS: Sentinel key for the maximum number of new tokens to generate.
  • SYSTEM_PROMPT: Sentinel key for the system prompt string.
  • TEMPERATURE: Key for the sampling temperature (passed through to the backend).
  • CONTEXT_WINDOW: Sentinel key for the context window size.
  • THINKING: Sentinel key for enabling/configuring reasoning/thinking mode.
  • SEED: Sentinel key for the random seed for reproducible generation.
  • STREAM: Sentinel key for enabling streaming responses.
Methods:

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FUNC replace_keys 

replace_keys(options: dict, from_to: dict[str, str]) -> dict[str, Any]
Return a new dict with selected keys in options renamed according to from_to. Returns a new dict with the keys in options replaced with the corresponding value for that key in from_to.
  • Any key with value == None is treated the same as the key missing.
  • If the destination key already exists in options, the original value is kept in the output.
  • Regardless of the presence of the destination key in options, the source key is always absent in the output.
Example: 
>>> options = {{"k1": "v1", "k2": "v2", "M1": "m1"}}
>>> from_to = {{"k1": "M1", "k2": "M2"}}

>>> new_options = replace_keys(options, from_to)
>>> print(new_options)
... {{"M1": "m1", "M2": "v2"}}
  • Notice that “M1” keeps the original value “m1”, rather than “v1”.
  • Notice that both “k1” and “k2” are absent in the output.
Args:
  • options: The source dictionary whose keys may be renamed.
  • from_to: Mapping of old key names to new key names.
Returns:
  • dict[str, Any]: A new dictionary with the specified keys renamed.

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FUNC remove_special_keys 

remove_special_keys(model_options: dict[str, Any]) -> dict[str, Any]
Return a copy of model_options with all sentinel-valued keys removed. Sentinel keys are those whose names start with @@@ (e.g. ModelOption.TOOLS). These are Mellea-internal keys that must not be forwarded to backend APIs. Args:
  • model_options: A model options dictionary that may contain sentinel keys.
Returns:
  • dict[str, Any]: A new dictionary with all @@@-prefixed keys omitted.

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FUNC merge_model_options 

merge_model_options(persistent_opts: dict[str, Any], overwrite_opts: dict[str, Any] | None) -> dict[str, Any]
Merge two model-options dicts, with overwrite_opts taking precedence on conflicts. Creates a new dict that contains all keys and values from persistent opts and overwrite opts. If there are duplicate keys, overwrite opts key value pairs will be used. Args:
  • persistent_opts: Base model options (lower precedence).
  • overwrite_opts: Per-call model options that override persistent_opts on key conflicts; None is treated as empty.
Returns:
  • dict[str, Any]: A new merged dictionary.