🧠 feat: Reasoning UI for Agents (#5904)

* chore: bump https-proxy-agent and @librechat/agents

* refactor: Improve error logging in OllamaClient for API fetch failures

* feat: Add DeepSeek provider support and enhance provider name handling

* refactor: Use Providers.OLLAMA constant for model name check in fetchModels function

* feat: Enhance formatAgentMessages to handle reasoning content type

* feat: OpenRouter Agent Reasoning

* hard work and dedicationgit add .env.example :)

* fix: Handle Google social login with missing last name

Social login with Google was previously displaying 'undefined' when
a user's last name was empty or not provided.

Changes:
- Conditionally render last name only if it exists
- Prevent displaying 'undefined' when last name is missing

* fix: add missing file endings for developers yml,yaml and log

---------

Co-authored-by: Mohamed Al-Duraji <mbalduraji@college.harvard.edu>
Co-authored-by: Deepak Kendole <deepakdpk101@gmail.com>
Co-authored-by: Peter Rothlaender <peter.rothlaender@ginkgo.com>

api/app/clients/OllamaClient.js

@@ -2,7 +2,7 @@ const { z } = require('zod');
 const axios = require('axios');
 const { Ollama } = require('ollama');
 const { Constants } = require('librechat-data-provider');
-const { deriveBaseURL } = require('~/utils');
+const { deriveBaseURL, logAxiosError } = require('~/utils');
 const { sleep } = require('~/server/utils');
 const { logger } = require('~/config');
 
@@ -68,7 +68,7 @@ class OllamaClient {
     } catch (error) {
       const logMessage =
         'Failed to fetch models from Ollama API. If you are not using Ollama directly, and instead, through some aggregator or reverse proxy that handles fetching via OpenAI spec, ensure the name of the endpoint doesn\'t start with `ollama` (case-insensitive).';
-      logger.error(logMessage, error);
+      logAxiosError({ message: logMessage, error });
       return [];
     }
   }

api/app/clients/OpenAIClient.js

@@ -7,6 +7,7 @@ const {
   ImageDetail,
   EModelEndpoint,
   resolveHeaders,
+  KnownEndpoints,
   openAISettings,
   ImageDetailCost,
   CohereConstants,
@@ -116,11 +117,7 @@ class OpenAIClient extends BaseClient {
 
     const { reverseProxyUrl: reverseProxy } = this.options;
 
-    if (
-      !this.useOpenRouter &&
-      reverseProxy &&
-      reverseProxy.includes('https://openrouter.ai/api/v1')
-    ) {
+    if (!this.useOpenRouter && reverseProxy && reverseProxy.includes(KnownEndpoints.openrouter)) {
       this.useOpenRouter = true;
     }
 

api/app/clients/prompts/formatAgentMessages.spec.js

@@ -282,4 +282,47 @@ describe('formatAgentMessages', () => {
     // Additional check to ensure the consecutive assistant messages were combined
     expect(result[1].content).toHaveLength(2);
   });
+
+  it('should skip THINK type content parts', () => {
+    const payload = [
+      {
+        role: 'assistant',
+        content: [
+          { type: ContentTypes.TEXT, [ContentTypes.TEXT]: 'Initial response' },
+          { type: ContentTypes.THINK, [ContentTypes.THINK]: 'Reasoning about the problem...' },
+          { type: ContentTypes.TEXT, [ContentTypes.TEXT]: 'Final answer' },
+        ],
+      },
+    ];
+
+    const result = formatAgentMessages(payload);
+
+    expect(result).toHaveLength(1);
+    expect(result[0]).toBeInstanceOf(AIMessage);
+    expect(result[0].content).toEqual('Initial response\nFinal answer');
+  });
+
+  it('should join TEXT content as string when THINK content type is present', () => {
+    const payload = [
+      {
+        role: 'assistant',
+        content: [
+          { type: ContentTypes.THINK, [ContentTypes.THINK]: 'Analyzing the problem...' },
+          { type: ContentTypes.TEXT, [ContentTypes.TEXT]: 'First part of response' },
+          { type: ContentTypes.TEXT, [ContentTypes.TEXT]: 'Second part of response' },
+          { type: ContentTypes.TEXT, [ContentTypes.TEXT]: 'Final part of response' },
+        ],
+      },
+    ];
+
+    const result = formatAgentMessages(payload);
+
+    expect(result).toHaveLength(1);
+    expect(result[0]).toBeInstanceOf(AIMessage);
+    expect(typeof result[0].content).toBe('string');
+    expect(result[0].content).toBe(
+      'First part of response\nSecond part of response\nFinal part of response',
+    );
+    expect(result[0].content).not.toContain('Analyzing the problem...');
+  });
 });

api/app/clients/prompts/formatMessages.js

@@ -153,6 +153,7 @@ const formatAgentMessages = (payload) => {
     let currentContent = [];
     let lastAIMessage = null;
 
+    let hasReasoning = false;
     for (const part of message.content) {
       if (part.type === ContentTypes.TEXT && part.tool_call_ids) {
         /*
@@ -207,11 +208,25 @@ const formatAgentMessages = (payload) => {
             content: output || '',
           }),
         );
+      } else if (part.type === ContentTypes.THINK) {
+        hasReasoning = true;
+        continue;
       } else {
         currentContent.push(part);
       }
     }
 
+    if (hasReasoning) {
+      currentContent = currentContent
+        .reduce((acc, curr) => {
+          if (curr.type === ContentTypes.TEXT) {
+            return `${acc}${curr[ContentTypes.TEXT]}\n`;
+          }
+          return acc;
+        }, '')
+        .trim();
+    }
+
     if (currentContent.length > 0) {
       messages.push(new AIMessage({ content: currentContent }));
     }