🏗️ fix: Agents Token Spend Race Conditions, Add Auto-refill Tx, Add Relevant Tests (#6480)

* 🏗️ refactor: Improve spendTokens logic to handle zero completion tokens and enhance test coverage

* 🏗️ test: Add tests to ensure balance does not go below zero when spending tokens

* 🏗️ fix: Ensure proper continuation in AgentClient when handling errors

* fix: spend token race conditions

* 🏗️ test: Add test for handling multiple concurrent transactions with high balance

* fix: Handle Omni models prompt prefix handling for user messages with array content in OpenAIClient

* refactor: Update checkBalance import paths to use new balanceMethods module

* refactor: Update checkBalance imports and implement updateBalance function for atomic balance updates

* fix: import from replace method

* feat: Add createAutoRefillTransaction method to handle non-balance updating transactions

* refactor: Move auto-refill logic to balanceMethods and enhance checkBalance functionality

* feat: Implement logging for auto-refill transactions in balance checks

* refactor: Remove logRefill calls from multiple client and handler files

* refactor: Move balance checking and auto-refill logic to balanceMethods for improved structure

* refactor: Simplify balance check calls by removing unnecessary balanceRecord assignments

* fix: Prevent negative rawAmount in spendTokens when promptTokens is zero

* fix: Update balanceMethods to use Balance model for findOneAndUpdate

* chore: import order

* refactor: remove unused txMethods file to streamline codebase

* feat: enhance updateBalance and createAutoRefillTransaction methods to support additional parameters for improved balance management

api/app/clients/BaseClient.js

@@ -11,9 +11,9 @@ const {
   Constants,
 } = require('librechat-data-provider');
 const { getMessages, saveMessage, updateMessage, saveConvo, getConvo } = require('~/models');
+const { checkBalance } = require('~/models/balanceMethods');
 const { truncateToolCallOutputs } = require('./prompts');
 const { addSpaceIfNeeded } = require('~/server/utils');
-const checkBalance = require('~/models/checkBalance');
 const { getFiles } = require('~/models/File');
 const TextStream = require('./TextStream');
 const { logger } = require('~/config');

api/app/clients/OpenAIClient.js

@@ -5,6 +5,7 @@ const { SplitStreamHandler, GraphEvents } = require('@librechat/agents');
 const {
   Constants,
   ImageDetail,
+  ContentTypes,
   EModelEndpoint,
   resolveHeaders,
   KnownEndpoints,
@@ -505,8 +506,24 @@ class OpenAIClient extends BaseClient {
     if (promptPrefix && this.isOmni === true) {
       const lastUserMessageIndex = payload.findLastIndex((message) => message.role === 'user');
       if (lastUserMessageIndex !== -1) {
-        payload[lastUserMessageIndex].content =
-          `${promptPrefix}\n${payload[lastUserMessageIndex].content}`;
+        if (Array.isArray(payload[lastUserMessageIndex].content)) {
+          const firstTextPartIndex = payload[lastUserMessageIndex].content.findIndex(
+            (part) => part.type === ContentTypes.TEXT,
+          );
+          if (firstTextPartIndex !== -1) {
+            const firstTextPart = payload[lastUserMessageIndex].content[firstTextPartIndex];
+            payload[lastUserMessageIndex].content[firstTextPartIndex].text =
+              `${promptPrefix}\n${firstTextPart.text}`;
+          } else {
+            payload[lastUserMessageIndex].content.unshift({
+              type: ContentTypes.TEXT,
+              text: promptPrefix,
+            });
+          }
+        } else {
+          payload[lastUserMessageIndex].content =
+            `${promptPrefix}\n${payload[lastUserMessageIndex].content}`;
+        }
       }
     }
 

api/app/clients/PluginsClient.js

@@ -5,8 +5,8 @@ const { addImages, buildErrorInput, buildPromptPrefix } = require('./output_pars
 const { initializeCustomAgent, initializeFunctionsAgent } = require('./agents');
 const { processFileURL } = require('~/server/services/Files/process');
 const { EModelEndpoint } = require('librechat-data-provider');
+const { checkBalance } = require('~/models/balanceMethods');
 const { formatLangChainMessages } = require('./prompts');
-const checkBalance = require('~/models/checkBalance');
 const { extractBaseURL } = require('~/utils');
 const { loadTools } = require('./tools/util');
 const { logger } = require('~/config');

api/app/clients/callbacks/createStartHandler.js

@@ -2,7 +2,7 @@ const { promptTokensEstimate } = require('openai-chat-tokens');
 const { EModelEndpoint, supportsBalanceCheck } = require('librechat-data-provider');
 const { formatFromLangChain } = require('~/app/clients/prompts');
 const { getBalanceConfig } = require('~/server/services/Config');
-const checkBalance = require('~/models/checkBalance');
+const { checkBalance } = require('~/models/balanceMethods');
 const { logger } = require('~/config');
 
 const createStartHandler = ({