Anthropic Claude Platform max_tokens requirement accommodation

Author: AvantMaker

library.properties

@@ -1,5 +1,5 @@
 name=ESP32_AI_Connect
-version=0.5.0.11
+version=0.5.0.12
 author=AvantMaker <admin@avantmaker.com> (and AI Assistant)
 maintainer=AvantMaker <admin@avantmaker.com>
 sentence=A library for ESP32 to interact with various AI APIs (OpenAI, Gemini, DeepSeek, etc.).

src/AI_API_Claude.cpp

@@ -58,9 +58,11 @@ String AI_API_Claude_Handler::buildRequestBody(const String& modelName, const St
             doc["temperature"] = temperature;
         }
 
-        if (maxTokens > 0) {
-            doc["max_tokens"] = maxTokens;
-        }
+        // IMPORTANT: Claude API requires 'max_tokens' field - it cannot be omitted
+        // According to Anthropic documentation: https://docs.anthropic.com/en/api/messages
+        // The 'max_tokens' field is required and cannot be left empty
+        // Use provided value if > 0, otherwise use default of 1024
+        doc["max_tokens"] = (maxTokens > 0) ? maxTokens : 1024;
 
         // Add system message if specified (only if user has set it with setTCChatSystemRole)
         if (systemRole.length() > 0) {
@@ -161,8 +163,10 @@ String AI_API_Claude_Handler::buildToolCallsRequestBody(const String& modelName,
         // Set the model
         doc["model"] = modelName;
 
-        // Add max_tokens parameter (required for Claude's tool calls API)
-        // Use default value of 1024 if not provided
+        // IMPORTANT: Claude API requires 'max_tokens' field - it cannot be omitted
+        // According to Anthropic documentation: https://docs.anthropic.com/en/api/messages
+        // The 'max_tokens' field is required and cannot be left empty
+        // Use provided value if > 0, otherwise use default of 1024
         doc["max_tokens"] = (maxTokens > 0) ? maxTokens : 1024;
 
         // Add system message if specified (only if user has set it with setTCChatSystemRole)
@@ -442,8 +446,10 @@ String AI_API_Claude_Handler::buildToolCallsFollowUpRequestBody(const String& mo
         // Set the model
         doc["model"] = modelName;
 
-        // Add max_tokens parameter (required for Claude's tool calls API)
-        // Use default value of 1024 if not provided
+        // IMPORTANT: Claude API requires 'max_tokens' field - it cannot be omitted
+        // According to Anthropic documentation: https://docs.anthropic.com/en/api/messages
+        // The 'max_tokens' field is required and cannot be left empty
+        // Use provided value if > 0, otherwise use default of 1024
         doc["max_tokens"] = (followUpMaxTokens > 0) ? followUpMaxTokens : 1024;
 
         // Add system message if specified (only if user has set it with setTCChatSystemRole)
@@ -759,9 +765,11 @@ String AI_API_Claude_Handler::buildStreamRequestBody(const String& modelName, co
             doc["temperature"] = temperature;
         }
 
-        if (maxTokens > 0) {
-            doc["max_tokens"] = maxTokens;
-        }
+        // IMPORTANT: Claude API requires 'max_tokens' field - it cannot be omitted
+        // According to Anthropic documentation: https://docs.anthropic.com/en/api/messages
+        // The 'max_tokens' field is required and cannot be left empty
+        // Use provided value if > 0, otherwise use default of 1024
+        doc["max_tokens"] = (maxTokens > 0) ? maxTokens : 1024;
 
         // Add system message if specified
         if (systemRole.length() > 0) {

src/AI_API_Claude.h

@@ -3,6 +3,22 @@
 
 #include "AI_API_Platform_Handler.h"
 
+/**
+ * AI_API_Claude_Handler - Handler for Anthropic Claude API
+ * 
+ * IMPORTANT CLAUDE API REQUIREMENTS:
+ * - The 'max_tokens' field is REQUIRED and cannot be omitted from requests
+ * - According to Anthropic documentation: https://docs.anthropic.com/en/api/messages
+ * - All request methods automatically include max_tokens with default value 1024
+ * - If user sets maxTokens > 0, that value is used instead of default
+ * 
+ * This handler supports:
+ * - Regular chat messages
+ * - Tool calling (function calling)
+ * - Streaming chat
+ * - System prompts
+ * - Custom parameters via setChatParameters()
+ */
 class AI_API_Claude_Handler : public AI_API_Platform_Handler {
 public:
     // Constructor and destructor