docs: add reasoning content to docs

docs/my-website/docs/providers/bedrock.md

@@ -443,7 +443,7 @@ curl http://0.0.0.0:4000/v1/chat/completions \
 
 **Expected Response**
 
-Same as Anthropic API response.
+Same as [Anthropic API response](../providers/anthropic#usage---thinking--reasoning_content).
 
 ```python
 {

docs/my-website/docs/reasoning_content.md

@@ -0,0 +1,105 @@
+import Tabs from '@theme/Tabs';
+import TabItem from '@theme/TabItem';
+
+# 'Thinking' / 'Reasoning Content'
+
+Supported Providers:
+- Deepseek (`deepseek/`)
+- Anthropic API (`anthropic/`)
+- Bedrock (Anthropic) (`bedrock/`)
+- Vertex AI (Anthropic) (`vertexai/`)
+
+```python
+"message": {
+    ...
+    "reasoning_content": "The capital of France is Paris.",
+    "thinking_blocks": [
+        {
+            "type": "thinking",
+            "thinking": "The capital of France is Paris.",
+            "signature_delta": "EqoBCkgIARABGAIiQL2UoU0b1OHYi+..."
+        }
+    ]
+}
+```
+
+## Quick Start 
+
+<Tabs>
+<TabItem value="sdk" label="SDK">
+
+```python
+from litellm import completion
+import os 
+
+os.environ["ANTHROPIC_API_KEY"] = ""
+
+response = completion(
+  model="anthropic/claude-3-7-sonnet-20250219",
+  messages=[
+    {"role": "user", "content": "What is the capital of France?"},
+  ],
+  thinking={"type": "enabled", "budget_tokens": 1024} # 👈 REQUIRED FOR ANTHROPIC models (on `anthropic/`, `bedrock/`, `vertexai/`)
+)
+print(response.choices[0].message.content)
+```
+
+</TabItem>
+<TabItem value="proxy" label="PROXY">
+
+```bash
+curl http://0.0.0.0:4000/v1/chat/completions \
+  -H "Content-Type: application/json" \
+  -H "Authorization: Bearer $LITELLM_KEY" \
+  -d '{
+    "model": "anthropic/claude-3-7-sonnet-20250219",
+    "messages": [
+      {
+        "role": "user",
+        "content": "What is the capital of France?"
+      }
+    ],
+    "thinking": {"type": "enabled", "budget_tokens": 1024}
+}'
+```
+</TabItem>
+</Tabs>
+
+**Expected Response**
+
+```bash
+{
+    "id": "3b66124d79a708e10c603496b363574c",
+    "choices": [
+        {
+            "finish_reason": "stop",
+            "index": 0,
+            "message": {
+                "content": " won the FIFA World Cup in 2022.",
+                "role": "assistant",
+                "tool_calls": null,
+                "function_call": null
+            }
+        }
+    ],
+    "created": 1723323084,
+    "model": "deepseek/deepseek-chat",
+    "object": "chat.completion",
+    "system_fingerprint": "fp_7e0991cad4",
+    "usage": {
+        "completion_tokens": 12,
+        "prompt_tokens": 16,
+        "total_tokens": 28,
+    },
+    "service_tier": null
+}
+```
+
+## Spec 
+
+- `reasoning_content` - str: The reasoning content from the model.
+- `thinking_blocks` - Optional[List[Dict[str, str]]]: A list of thinking blocks from the model. Only returned for Anthropic models.
+  - `type` - str: The type of thinking block.
+  - `thinking` - str: The thinking from the model.
+  - `signature_delta` - str: The signature delta from the model.
+

docs/my-website/sidebars.js

@@ -242,6 +242,7 @@ const sidebars = {
         "completion/document_understanding",
         "completion/vision",
         "completion/json_mode",
+        "reasoning_content",
         "completion/prompt_caching",
         "completion/predict_outputs",
         "completion/prefix",