Function pruneStringFromTop

core/llm/countTokens.ts:353–366

(
  modelName: string,
  maxTokens: number,
  prompt: string,
)

}

function pruneStringFromTop(
  modelName: string,
  maxTokens: number,
  prompt: string,
): string {
  const encoding = encodingForModel(modelName);

  const tokens = encoding.encode(prompt, "all", []);
  if (tokens.length <= maxTokens) {
    return prompt;
  }

  return encoding.decode(tokens.slice(tokens.length - maxTokens));
}

const MAX_TOKEN_SAFETY_BUFFER = 1000;
const TOKEN_SAFETY_PROPORTION = 0.02;