mellea.stdlib.sampling.budget_forcing

Sampling Strategies for budget forcing generation.

Classes

CLASS BudgetForcingSamplingStrategy

Sampling strategy that enforces a token budget for chain-of-thought reasoning.

Extends RejectionSamplingStrategy with explicit control over the <think> block size and the answer block size. On each loop iteration, think_budget_forcing interleaves forced-thinking and final-answer generation, after which the standard rejection-sampling validation pass determines whether to accept or retry.

Currently only supports the OllamaModelBackend.

Args:

• think_max_tokens: Tokens allocated for the thinking block. Defaults to 4096.
• answer_max_tokens: Tokens allocated for the answer block. None means unbounded.
• start_think_token: Token opening the thinking block. Defaults to "<think>".
• end_think_token: Token closing the thinking block. Defaults to "</think>".
• begin_response_token: Optional token opening the response block. Defaults to "".
• end_response_token: Token closing the response block.
• think_more_suffix: Suffix to force continued thinking. Empty string disables forcing.
• answer_suffix: Suffix to elicit a final answer.
• loop_budget: Rejection-sampling loop count. Must be > 0.
• requirements: Requirements to validate against.