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Shared utility functions used across formatter-based backend implementations. Provides to_chat, which converts a [Context](../core/base#class-context) and a [Component](../core/base#class-component) action into the list of role/content dicts expected by apply_chat_template; and to_tool_calls, which parses a raw model output string into validated [ModelToolCall](../core/base#class-modeltoolcall) objects. These helpers are consumed internally by all [FormatterBackend](backend#class-formatterbackend) subclasses.

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Functions

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FUNC get_value 

get_value(obj: Any, key: str) -> Any
Get value from dict or object attribute. Args:
  • obj: Dict or object
  • key: Key or attribute name
Returns:
  • Value if found, None otherwise

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FUNC to_chat 

to_chat(action: Component | CBlock, ctx: Context, formatter: ChatFormatter, system_prompt: str | None) -> list[Chat]
Converts a context and an action into a series of dicts to be passed to apply_chat_template. This function is used by local inference backends. Args:
  • action: The next component or CBlock to generate output for.
  • ctx: The current conversation context.
  • formatter: The chat formatter used to convert context and action to messages.
  • system_prompt: Optional system prompt to prepend; overrides any system message in the context.
Returns:
  • List of role/content dicts suitable for apply_chat_template.

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FUNC to_tool_calls 

to_tool_calls(tools: dict[str, AbstractMelleaTool], decoded_result: str) -> dict[str, ModelToolCall] | None
Parse a tool call string. Args:
  • tools: Mapping of tool name to the corresponding AbstractMelleaTool object.
  • decoded_result: Raw model output string that may contain tool call markup.
Returns:
  • Dict mapping tool name to validated [ModelToolCall](../core/base#class-modeltoolcall), or None if no tool calls were found.