@copilotkit/runtime/src/service-adapters/openai/utils.ts

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import { Message } from "../../graphql/types/converted";
import { ActionInput } from "../../graphql/inputs/action.input";
import {
  ChatCompletionAssistantMessageParam,
  ChatCompletionMessageParam,
  ChatCompletionSystemMessageParam,
  ChatCompletionTool,
  ChatCompletionUserMessageParam,
  ChatCompletionDeveloperMessageParam,
} from "openai/resources/chat";
import { parseJson } from "@copilotkit/shared";

export function limitMessagesToTokenCount(
  messages: any[],
  tools: any[],
  model: string,
  maxTokens?: number,
): any[] {
  maxTokens ||= maxTokensForOpenAIModel(model);

  const result: any[] = [];
  const toolsNumTokens = countToolsTokens(model, tools);
  if (toolsNumTokens > maxTokens) {
    throw new Error(`Too many tokens in function definitions: ${toolsNumTokens} > ${maxTokens}`);
  }
  maxTokens -= toolsNumTokens;

  for (const message of messages) {
    if (["system", "developer"].includes(message.role)) {
      const numTokens = countMessageTokens(model, message);
      maxTokens -= numTokens;

      if (maxTokens < 0) {
        throw new Error("Not enough tokens for system message.");
      }
    }
  }

  let cutoff: boolean = false;

  const reversedMessages = [...messages].reverse();
  for (const message of reversedMessages) {
    if (["system", "developer"].includes(message.role)) {
      result.unshift(message);
      continue;
    } else if (cutoff) {
      continue;
    }
    let numTokens = countMessageTokens(model, message);
    if (maxTokens < numTokens) {
      cutoff = true;
      continue;
    }
    result.unshift(message);
    maxTokens -= numTokens;
  }

  return result;
}

export function maxTokensForOpenAIModel(model: string): number {
  return maxTokensByModel[model] || DEFAULT_MAX_TOKENS;
}

const DEFAULT_MAX_TOKENS = 128000;

const maxTokensByModel: { [key: string]: number } = {
  // o1
  o1: 200000,
  "o1-2024-12-17": 200000,
  "o1-mini": 128000,
  "o1-mini-2024-09-12": 128000,
  "o1-preview": 128000,
  "o1-preview-2024-09-12": 128000,
  // o3-mini
  "o3-mini": 200000,
  "o3-mini-2025-01-31": 200000,
  // GPT-4
  "gpt-4o": 128000,
  "chatgpt-4o-latest": 128000,
  "gpt-4o-2024-08-06": 128000,
  "gpt-4o-2024-05-13": 128000,
  "gpt-4o-mini": 128000,
  "gpt-4o-mini-2024-07-18": 128000,
  "gpt-4-turbo": 128000,
  "gpt-4-turbo-2024-04-09": 128000,
  "gpt-4-0125-preview": 128000,
  "gpt-4-turbo-preview": 128000,
  "gpt-4-1106-preview": 128000,
  "gpt-4-vision-preview": 128000,
  "gpt-4-1106-vision-preview": 128000,
  "gpt-4-32k": 32768,
  "gpt-4-32k-0613": 32768,
  "gpt-4-32k-0314": 32768,
  "gpt-4": 8192,
  "gpt-4-0613": 8192,
  "gpt-4-0314": 8192,

  // GPT-3.5
  "gpt-3.5-turbo-0125": 16385,
  "gpt-3.5-turbo": 16385,
  "gpt-3.5-turbo-1106": 16385,
  "gpt-3.5-turbo-instruct": 4096,
  "gpt-3.5-turbo-16k": 16385,
  "gpt-3.5-turbo-0613": 4096,
  "gpt-3.5-turbo-16k-0613": 16385,
  "gpt-3.5-turbo-0301": 4097,
};

function countToolsTokens(model: string, tools: any[]): number {
  if (tools.length === 0) {
    return 0;
  }
  const json = JSON.stringify(tools);
  return countTokens(model, json);
}

function countMessageTokens(model: string, message: any): number {
  return countTokens(model, message.content || "");
}

function countTokens(model: string, text: string): number {
  return text.length / 3;
}

export function convertActionInputToOpenAITool(action: ActionInput): ChatCompletionTool {
  return {
    type: "function",
    function: {
      name: action.name,
      description: action.description,
      parameters: parseJson(action.jsonSchema, {}),
    },
  };
}

type UsedMessageParams =
  | ChatCompletionUserMessageParam
  | ChatCompletionAssistantMessageParam
  | ChatCompletionDeveloperMessageParam
  | ChatCompletionSystemMessageParam;
export function convertMessageToOpenAIMessage(
  message: Message,
  options?: { keepSystemRole: boolean },
): ChatCompletionMessageParam {
  const { keepSystemRole } = options || { keepSystemRole: false };
  if (message.isTextMessage()) {
    let role = message.role as UsedMessageParams["role"];
    if (message.role === "system" && !keepSystemRole) {
      role = "developer";
    }
    return {
      role,
      content: message.content,
    } satisfies UsedMessageParams;
  } else if (message.isImageMessage()) {
    return {
      role: "user",
      content: [
        {
          type: "image_url",
          image_url: {
            url: `data:image/${message.format};base64,${message.bytes}`,
          },
        },
      ],
    } satisfies UsedMessageParams;
  } else if (message.isActionExecutionMessage()) {
    return {
      role: "assistant",
      tool_calls: [
        {
          id: message.id,
          type: "function",
          function: {
            name: message.name,
            arguments: JSON.stringify(message.arguments),
          },
        },
      ],
    };
  } else if (message.isResultMessage()) {
    return {
      role: "tool",
      content: message.result,
      tool_call_id: message.actionExecutionId,
    };
  }
}

export function convertSystemMessageToAssistantAPI(message: ChatCompletionMessageParam) {
  return {
    ...message,
    ...(["system", "developer"].includes(message.role) && {
      role: "assistant",
      content: "THE FOLLOWING MESSAGE IS A SYSTEM MESSAGE: " + message.content,
    }),
  };
}