docs: simplify examples to cURL only

Remove TypeScript and Python code examples, keeping only cURL for cleaner documentation.

VAP-11219

Co-Authored-By: Claude <noreply@anthropic.com>

Author: vapi-tasker[bot]

fern/chat/variable-substitution.mdx

@@ -27,8 +27,7 @@ When you create a session with `assistantOverrides.variableValues`, the system:
 3. Stores the **pre-substituted assistant** in the session
 4. Saves the original variable values in `session.metadata.variableValues` for reference
 
-<CodeBlocks>
-```bash title="cURL"
+```bash title="Create session with variables"
 curl -X POST https://api.vapi.ai/session \
   -H "Authorization: Bearer $VAPI_API_KEY" \
   -H "Content-Type: application/json" \
@@ -42,29 +41,6 @@ curl -X POST https://api.vapi.ai/session \
     }
   }'
 ```
-```typescript title="TypeScript"
-const session = await vapi.sessions.create({
-  assistantId: "your-assistant-id",
-  assistantOverrides: {
-    variableValues: {
-      name: "John",
-      company: "Acme Corp"
-    }
-  }
-});
-```
-```python title="Python"
-session = vapi.sessions.create(
-    assistant_id="your-assistant-id",
-    assistant_overrides={
-        "variableValues": {
-            "name": "John",
-            "company": "Acme Corp"
-        }
-    }
-)
-```
-</CodeBlocks>
 
 If your assistant's system prompt was `"You are a helpful assistant for {{name}} at {{company}}"`, the session stores: `"You are a helpful assistant for John at Acme Corp"`.
 
@@ -84,9 +60,7 @@ When you send a chat request with a `sessionId`:
 
 Once you set variables at session creation, they persist for all chats in that session:
 
-<CodeBlocks>
-```bash title="cURL"
-# Chat using the session - variables already applied
+```bash title="Chat using the session"
 curl -X POST https://api.vapi.ai/chat \
   -H "Authorization: Bearer $VAPI_API_KEY" \
   -H "Content-Type: application/json" \
@@ -95,21 +69,6 @@ curl -X POST https://api.vapi.ai/chat \
     "input": "What is my name and company?"
   }'
 ```
-```typescript title="TypeScript"
-const chat = await vapi.chat.create({
-  sessionId: "session_xyz789",
-  input: "What is my name and company?"
-});
-// Response will reference "John" and "Acme Corp"
-```
-```python title="Python"
-chat = vapi.chat.create(
-    session_id="session_xyz789",
-    input="What is my name and company?"
-)
-# Response will reference "John" and "Acme Corp"
-```
-</CodeBlocks>
 
 The assistant will respond with the values set at session creation (John, Acme Corp).
 
@@ -119,9 +78,7 @@ The assistant will respond with the values set at session creation (John, Acme C
 Passing new `variableValues` in a chat request **will not** change the session's pre-substituted assistant. The template placeholders no longer exist.
 </Warning>
 
-<CodeBlocks>
-```bash title="cURL"
-# This will NOT change the assistant's context
+```bash title="This will NOT change the assistant's context"
 curl -X POST https://api.vapi.ai/chat \
   -H "Authorization: Bearer $VAPI_API_KEY" \
   -H "Content-Type: application/json" \
@@ -136,44 +93,14 @@ curl -X POST https://api.vapi.ai/chat \
     }
   }'
 ```
-```typescript title="TypeScript"
-// This will NOT change the assistant's context
-const chat = await vapi.chat.create({
-  sessionId: "session_xyz789",
-  input: "What is my name and company?",
-  assistantOverrides: {
-    variableValues: {
-      name: "Jane",
-      company: "Wayne Enterprises"
-    }
-  }
-});
-// Response will STILL reference "John" and "Acme Corp"
-```
-```python title="Python"
-# This will NOT change the assistant's context
-chat = vapi.chat.create(
-    session_id="session_xyz789",
-    input="What is my name and company?",
-    assistant_overrides={
-        "variableValues": {
-            "name": "Jane",
-            "company": "Wayne Enterprises"
-        }
-    }
-)
-# Response will STILL reference "John" and "Acme Corp"
-```
-</CodeBlocks>
 
 The assistant still responds with "John" and "Acme Corp" because the original templates were already replaced.
 
 ### Provide fresh templates to use new values
 
 To use different variable values mid-session, provide a new template with `{{ }}` placeholders along with the new values:
 
-<CodeBlocks>
-```bash title="cURL"
+```bash title="Override with fresh template"
 curl -X POST https://api.vapi.ai/chat \
   -H "Authorization: Bearer $VAPI_API_KEY" \
   -H "Content-Type: application/json" \
@@ -193,43 +120,6 @@ curl -X POST https://api.vapi.ai/chat \
     }
   }'
 ```
-```typescript title="TypeScript"
-const chat = await vapi.chat.create({
-  sessionId: "session_xyz789",
-  input: "What is my name and company?",
-  assistantOverrides: {
-    model: {
-      provider: "openai",
-      model: "gpt-4.1",
-      systemPrompt: "You are a helpful assistant for {{name}} at {{company}}. Be very formal."
-    },
-    variableValues: {
-      name: "Jane",
-      company: "Wayne Enterprises"
-    }
-  }
-});
-// Response will now reference "Jane" and "Wayne Enterprises"
-```
-```python title="Python"
-chat = vapi.chat.create(
-    session_id="session_xyz789",
-    input="What is my name and company?",
-    assistant_overrides={
-        "model": {
-            "provider": "openai",
-            "model": "gpt-4.1",
-            "systemPrompt": "You are a helpful assistant for {{name}} at {{company}}. Be very formal."
-        },
-        "variableValues": {
-            "name": "Jane",
-            "company": "Wayne Enterprises"
-        }
-    }
-)
-# Response will now reference "Jane" and "Wayne Enterprises"
-```
-</CodeBlocks>
 
 Now the assistant responds with "Jane" and "Wayne Enterprises" because fresh template placeholders were provided.
 
@@ -250,24 +140,7 @@ Now the assistant responds with "Jane" and "Wayne Enterprises" because fresh tem
 
 ### For consistent variables across a session
 
-Pass `assistantOverrides.variableValues` once when creating the session. Subsequent chat requests only need the `sessionId` and `input`:
-
-```typescript title="Recommended pattern"
-// 1. Create session with variables
-const session = await vapi.sessions.create({
-  assistantId: "your-assistant-id",
-  assistantOverrides: {
-    variableValues: {
-      customerName: "Sarah",
-      accountType: "Premium"
-    }
-  }
-});
-
-// 2. All chats use the session - variables persist
-await vapi.chat.create({ sessionId: session.id, input: "Hello!" });
-await vapi.chat.create({ sessionId: session.id, input: "What's my account type?" });
-```
+Pass `assistantOverrides.variableValues` once when creating the session. Subsequent chat requests only need the `sessionId` and `input`.
 
 ### For different variables per conversation
 
@@ -276,61 +149,12 @@ Choose one of these approaches:
 <AccordionGroup>
   <Accordion title="Option A: Don't use sessions">
     Pass the full assistant configuration in each chat request. This gives you complete control over variables per request.
-    
-    ```typescript
-    const chat = await vapi.chat.create({
-      assistantId: "your-assistant-id",
-      assistantOverrides: {
-        variableValues: {
-          customerName: "Different Customer",
-          accountType: "Basic"
-        }
-      },
-      input: "Hello!"
-    });
-    ```
   </Accordion>
   <Accordion title="Option B: Override with fresh templates">
     Include a new system prompt (or other text field) with `{{ }}` placeholders plus new `variableValues` in your chat request.
-    
-    ```typescript
-    const chat = await vapi.chat.create({
-      sessionId: "existing-session-id",
-      assistantOverrides: {
-        model: {
-          provider: "openai",
-          model: "gpt-4.1",
-          systemPrompt: "You assist {{customerName}} with their {{accountType}} account."
-        },
-        variableValues: {
-          customerName: "New Customer",
-          accountType: "Enterprise"
-        }
-      },
-      input: "Hello!"
-    });
-    ```
   </Accordion>
   <Accordion title="Option C: Create separate sessions">
     Create a new session for each unique variable context. This keeps conversations cleanly separated.
-    
-    ```typescript
-    // Session for Customer A
-    const sessionA = await vapi.sessions.create({
-      assistantId: "your-assistant-id",
-      assistantOverrides: {
-        variableValues: { customerName: "Customer A" }
-      }
-    });
-    
-    // Session for Customer B
-    const sessionB = await vapi.sessions.create({
-      assistantId: "your-assistant-id",
-      assistantOverrides: {
-        variableValues: { customerName: "Customer B" }
-      }
-    });
-    ```
   </Accordion>
 </AccordionGroup>