feat: Support toolcall parser for DeepSeek V3 and R1 (#4253)

Signed-off-by: zhangzhang <tangchenyu@xiaohongshu.com>
Co-authored-by: zhangzhang <tangchenyu@xiaohongshu.com>
Co-authored-by: Ayush Agarwal <ayushag@nvidia.com>

docs/agents/tool-calling.md

@@ -35,6 +35,7 @@ Parser to Model Mapping
 | harmony | openai/gpt-oss-* |
 | nemotron_deci | nvidia/nemotron-* |
 | phi4 | Phi-4-* |
+| deepseek_v3 | deepseek-ai/DeepSeek-V3, deepseek-ai/DeepSeek-R1, deepseek-ai/DeepSeek-R1-0528 |
 | deepseek_v3_1 | deepseek-ai/DeepSeek-V3.1 |
 | pythonic |  meta-llama/Llama-4-* |
 

lib/llm/tests/data/vllm/deepseek-v3.1/chat_completion_stream_no_tool.json

+{
+  "request_id": "deepseek-v3.1-no-tool-test",
+  "expected_output": {
+    "normal_content": "The weather in Beijing today is sunny with temperatures between 15 and 22 degrees Celsius. It's suitable for outdoor activities.",
+    "reasoning_content": "The user asked about the weather in Beijing, I will provide relevant weather information.",
+    "tool_calls": []
+  },
+  "input_stream": [
+    {"data":{"id":"chatcmpl-deepseek-v3.1-no-tool","choices":[{"index":0,"delta":{"content":"<think>The user asked about the weather in Beijing, I will provide relevant weather information.</think>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":"The user asked about the weather in Beijing, I will provide relevant weather information."}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-no-tool","choices":[{"index":0,"delta":{"content":"The weather in Beijing today is sunny with temperatures between 15 and 22 degrees Celsius. It's suitable for outdoor activities.","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-no-tool","choices":[{"index":0,"delta":{"content":null,"function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null},"finish_reason":"stop"}]}}
+  ]
+}
\ No newline at end of file

lib/llm/tests/data/vllm/deepseek-v3.1/chat_completion_stream_tool.json

+{
+  "request_id": "deepseek-v3.1-tool-call-test",
+  "expected_output": {
+    "normal_content": "",
+    "reasoning_content": "The user wants to check the weather in Beijing and Shanghai, I need to call the get_current_weather tool to get this information.",
+    "tool_calls": [
+      {
+        "id": "call_1",
+        "type": "function",
+        "function": {
+          "name": "get_current_weather",
+          "arguments": "{\"location\": \"Beijing\", \"format\": \"celsius\"}"
+        }
+      },
+      {
+        "id": "call_2",
+        "type": "function",
+        "function": {
+          "name": "get_current_weather",
+          "arguments": "{\"location\": \"Shanghai\", \"format\": \"celsius\"}"
+        }
+      }
+    ]
+  },
+  "input_stream": [
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<think>The user wants to check the weather in Beijing and Shanghai, I need to call the get_current_weather tool to get this information.</think>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":"The user wants to check the weather in Beijing and Shanghai, I need to call the get_current_weather tool to get this information."}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁calls▁begin｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁begin｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"get_current_weather","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁sep｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"{\"location\": \"Beijing\", \"format\": \"celsius\"}","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁end｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁begin｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"get_current_weather","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁sep｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"{\"location\": \"Shanghai\", \"format\": \"celsius\"}","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁end｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁calls▁end｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3.1-tool","choices":[{"index":0,"delta":{"content":null,"function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null},"finish_reason":"tool_calls"}]}}
+  ]
+}
\ No newline at end of file

lib/llm/tests/data/vllm/deepseek-v3/chat_completion_stream_no_tool.json

+{
+  "request_id": "deepseek-v3-no-tool-test",
+  "expected_output": {
+    "normal_content": "The weather in Beijing today is sunny with temperatures between 15 and 22 degrees Celsius. It's suitable for outdoor activities.",
+    "reasoning_content": "The user asked about the weather in Beijing, I will provide relevant weather information.",
+    "tool_calls": []
+  },
+  "input_stream": [
+    {"data":{"id":"chatcmpl-deepseek-v3-no-tool","choices":[{"index":0,"delta":{"content":"<think>The user asked about the weather in Beijing, I will provide relevant weather information.</think>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":"The user asked about the weather in Beijing, I will provide relevant weather information."}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-no-tool","choices":[{"index":0,"delta":{"content":"The weather in Beijing today is sunny with temperatures between 15 and 22 degrees Celsius. It's suitable for outdoor activities.","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-no-tool","choices":[{"index":0,"delta":{"content":null,"function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null},"finish_reason":"stop"}]}}
+  ]
+}
\ No newline at end of file

lib/llm/tests/data/vllm/deepseek-v3/chat_completion_stream_tool.json

+{
+  "request_id": "deepseek-v3-tool-call-test",
+  "expected_output": {
+    "normal_content": "",
+    "reasoning_content": "The user wants to check the weather in Beijing and Shanghai, I need to call the get_current_weather tool to get this information.",
+    "tool_calls": [
+      {
+        "id": "call_1",
+        "type": "function",
+        "function": {
+          "name": "get_current_weather",
+          "arguments": "{\"location\": \"Beijing\", \"format\": \"celsius\"}"
+        }
+      },
+      {
+        "id": "call_2",
+        "type": "function",
+        "function": {
+          "name": "get_current_weather",
+          "arguments": "{\"location\": \"Shanghai\", \"format\": \"celsius\"}"
+        }
+      }
+    ]
+  },
+  "input_stream": [
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<think>The user wants to check the weather in Beijing and Shanghai, I need to call the get_current_weather tool to get this information.</think>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":"The user wants to check the weather in Beijing and Shanghai, I need to call the get_current_weather tool to get this information."}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁calls▁begin｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁begin｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"function","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁sep｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"get_current_weather","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"\n```json\n","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"{\"location\": \"Beijing\", \"format\": \"celsius\"}\n","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"```","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁end｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁begin｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"function","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁sep｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"get_current_weather","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"\n```json\n","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"{\"location\": \"Shanghai\", \"format\": \"celsius\"}\n","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"```","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁call▁end｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":"<｜tool▁calls▁end｜>","function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null}}]}},
+    {"data":{"id":"chatcmpl-deepseek-v3-tool","choices":[{"index":0,"delta":{"content":null,"function_call":null,"tool_calls":null,"role":"assistant","refusal":null,"reasoning_content":null},"finish_reason":"tool_calls"}]}}
+  ]
+}
\ No newline at end of file

lib/llm/tests/test_streaming_tool_parsers.rs

@@ -881,4 +881,214 @@ mod tests {
             );
         }
     }
+
+    #[tokio::test]
+    async fn test_deepseek_v3_e2e_with_tools_vllm() {
+        // E2E Parsing test for DeepSeek V3 with tools.
+        let file_path = format!(
+            "{}/vllm/deepseek-v3/chat_completion_stream_tool.json",
+            DATA_ROOT_PATH
+        );
+        let test_data = load_test_data(&file_path);
+
+        // Create a stream from the mock chunks
+        let input_stream = stream::iter(test_data.stream_chunks);
+
+        // Parse the response stream with reasoning and tool parsing enabled
+        let output_chunks = parse_response_stream(
+            input_stream,
+            true,
+            true,
+            Some("deepseek_v3".to_string()),
+            Some("deepseek_v3".to_string()),
+        )
+        .await;
+
+        // Verify we got output chunks
+        assert!(!output_chunks.is_empty(), "Should have output chunks");
+
+        // Aggregate content from output chunks
+        let aggregated = aggregate_content_from_chunks(&output_chunks);
+
+        // Assert reasoning content was parsed
+        assert_eq!(
+            aggregated.reasoning_content, test_data.expected_reasoning_content,
+            "Should have extracted reasoning content.",
+        );
+
+        assert_eq!(
+            aggregated.normal_content, test_data.expected_normal_content,
+            "Normal content should match expected value.",
+        );
+
+        // Verify tool calls match expectations
+        let expected_has_tool_calls = !test_data.expected_tool_calls.is_empty();
+        assert_eq!(
+            aggregated.has_tool_calls, expected_has_tool_calls,
+            "Tool calls presence should match expected value"
+        );
+
+        // Verify tool calls
+        assert_tool_calls(&aggregated.tool_calls, &test_data.expected_tool_calls);
+
+        // Verify finish_reason is valid: exactly one occurrence, in last chunk, and is ToolCalls
+        assert!(
+            validate_finish_reason(&output_chunks, FinishReason::ToolCalls),
+            "finish_reason validation failed for tool call case"
+        );
+    }
+
+    #[tokio::test]
+    async fn test_deepseek_v3_1_e2e_with_tools_vllm() {
+        // E2E Parsing test for DeepSeek V3.1 with tools.
+        let file_path = format!(
+            "{}/vllm/deepseek-v3.1/chat_completion_stream_tool.json",
+            DATA_ROOT_PATH
+        );
+        let test_data = load_test_data(&file_path);
+
+        // Create a stream from the mock chunks
+        let input_stream = stream::iter(test_data.stream_chunks);
+
+        // Parse the response stream with reasoning and tool parsing enabled
+        let output_chunks = parse_response_stream(
+            input_stream,
+            true,
+            true,
+            Some("deepseek_v3_1".to_string()),
+            Some("deepseek_v3_1".to_string()),
+        )
+        .await;
+
+        // Verify we got output chunks
+        assert!(!output_chunks.is_empty(), "Should have output chunks");
+
+        // Aggregate content from output chunks
+        let aggregated = aggregate_content_from_chunks(&output_chunks);
+
+        // Assert reasoning content was parsed
+        assert_eq!(
+            aggregated.reasoning_content, test_data.expected_reasoning_content,
+            "Should have extracted reasoning content.",
+        );
+
+        assert_eq!(
+            aggregated.normal_content, test_data.expected_normal_content,
+            "Normal content should match expected value.",
+        );
+
+        // Verify tool calls match expectations
+        let expected_has_tool_calls = !test_data.expected_tool_calls.is_empty();
+        assert_eq!(
+            aggregated.has_tool_calls, expected_has_tool_calls,
+            "Tool calls presence should match expected value"
+        );
+
+        // Verify tool calls
+        assert_tool_calls(&aggregated.tool_calls, &test_data.expected_tool_calls);
+
+        // Verify finish_reason is valid: exactly one occurrence, in last chunk, and is ToolCalls
+        assert!(
+            validate_finish_reason(&output_chunks, FinishReason::ToolCalls),
+            "finish_reason validation failed for tool call case"
+        );
+    }
+
+    #[tokio::test]
+    async fn test_deepseek_v3_e2e_with_no_tools_vllm() {
+        // E2E Parsing test for DeepSeek V3 without tools.
+        let file_path = format!(
+            "{}/vllm/deepseek-v3/chat_completion_stream_no_tool.json",
+            DATA_ROOT_PATH
+        );
+        let test_data = load_test_data(&file_path);
+
+        // Create a stream from the mock chunks
+        let input_stream = stream::iter(test_data.stream_chunks);
+
+        // Parse the response stream with reasoning and tool parsing enabled
+        let output_chunks = parse_response_stream(
+            input_stream,
+            true,
+            true,
+            Some("deepseek_v3".to_string()),
+            Some("deepseek_v3".to_string()),
+        )
+        .await;
+
+        // Verify we got output chunks
+        assert!(!output_chunks.is_empty(), "Should have output chunks");
+
+        // Aggregate content from output chunks
+        let aggregated = aggregate_content_from_chunks(&output_chunks);
+
+        // Assert reasoning content was parsed
+        assert_eq!(
+            aggregated.reasoning_content, test_data.expected_reasoning_content,
+            "Should have extracted reasoning content.",
+        );
+
+        assert_eq!(
+            aggregated.normal_content, test_data.expected_normal_content,
+            "Normal content should match expected value.",
+        );
+
+        // Verify no tool calls
+        assert!(!aggregated.has_tool_calls, "Should not have any tool calls");
+
+        // Verify finish_reason is valid: exactly one occurrence, in last chunk, and is Stop
+        assert!(
+            validate_finish_reason(&output_chunks, FinishReason::Stop),
+            "finish_reason validation failed for non-tool call case"
+        );
+    }
+
+    #[tokio::test]
+    async fn test_deepseek_v3_1_e2e_with_no_tools_vllm() {
+        // E2E Parsing test for DeepSeek V3.1 without tools.
+        let file_path = format!(
+            "{}/vllm/deepseek-v3.1/chat_completion_stream_no_tool.json",
+            DATA_ROOT_PATH
+        );
+        let test_data = load_test_data(&file_path);
+
+        // Create a stream from the mock chunks
+        let input_stream = stream::iter(test_data.stream_chunks);
+
+        // Parse the response stream with reasoning and tool parsing enabled
+        let output_chunks = parse_response_stream(
+            input_stream,
+            true,
+            true,
+            Some("deepseek_v3_1".to_string()),
+            Some("deepseek_v3_1".to_string()),
+        )
+        .await;
+
+        // Verify we got output chunks
+        assert!(!output_chunks.is_empty(), "Should have output chunks");
+
+        // Aggregate content from output chunks
+        let aggregated = aggregate_content_from_chunks(&output_chunks);
+
+        // Assert reasoning content was parsed
+        assert_eq!(
+            aggregated.reasoning_content, test_data.expected_reasoning_content,
+            "Should have extracted reasoning content.",
+        );
+
+        assert_eq!(
+            aggregated.normal_content, test_data.expected_normal_content,
+            "Normal content should match expected value.",
+        );
+
+        // Verify no tool calls
+        assert!(!aggregated.has_tool_calls, "Should not have any tool calls");
+
+        // Verify finish_reason is valid: exactly one occurrence, in last chunk, and is Stop
+        assert!(
+            validate_finish_reason(&output_chunks, FinishReason::Stop),
+            "finish_reason validation failed for non-tool call case"
+        );
+    }
 }

lib/parsers/src/tool_calling/config.rs

@@ -176,4 +176,20 @@ impl ToolCallConfig {
             },
         }
     }
+
+    pub fn deepseek_v3() -> Self {
+        // DeepSeek V3 format:
+        // <｜tool▁calls▁begin｜><｜tool▁call▁begin｜>{type}<｜tool▁sep｜>{function_name}\n```json\n{arguments}\n```<｜tool▁call▁end｜><｜tool▁calls▁end｜>
+        // There are some differences between DeepSeek V3 and DeepSeek V3.1
+        Self {
+            format: ToolCallParserType::Json,
+            json: JsonParserConfig {
+                tool_call_start_tokens: vec!["<｜tool▁calls▁begin｜>".to_string()],
+                tool_call_end_tokens: vec!["<｜tool▁calls▁end｜>".to_string()],
+                tool_call_separator_tokens: vec!["<｜tool▁sep｜>".to_string()],
+                parser_type: JsonParserType::DeepseekV3,
+                ..Default::default()
+            },
+        }
+    }
 }

lib/parsers/src/tool_calling/json/deepseek_parser.rs → lib/parsers/src/tool_calling/json/deepseek_v3_1_parser.rs

@@ -8,15 +8,15 @@ use uuid::Uuid;
 use super::config::JsonParserConfig;
 use super::response::{CalledFunction, ToolCallResponse, ToolCallType};
 
-/// Extract individual tool call blocks from the input string.
+/// Extract individual tool call blocks from the input string for DeepSeek V3.1 format.
 /// Returns a list of strings, each representing one tool call block.
 ///
-/// DeepSeek format: <｜tool▁call▁begin｜>{name}<｜tool▁sep｜>{args}<｜tool▁call▁end｜>
+/// DeepSeek V3.1 format: <｜tool▁call▁begin｜>{name}<｜tool▁sep｜>{args}<｜tool▁call▁end｜>
 ///
 /// DeepSeek uses nested tokens:
 /// - Wrapper tokens: <｜tool▁calls▁begin｜> ... <｜tool▁calls▁end｜> (wraps all tool calls)
 /// - Individual tokens: <｜tool▁call▁begin｜> ... <｜tool▁call▁end｜> (individual call)
-fn extract_tool_call_blocks(
+fn extract_tool_call_blocks_v3_1(
     input: &str,
     start_tokens: &[String],
     end_tokens: &[String],
@@ -74,7 +74,10 @@ fn extract_tool_call_blocks(
 /// Parse a single tool call block that contains function name and arguments separated by a separator token.
 ///
 /// Format: {function_name}<｜tool▁sep｜>{json_arguments}
-fn parse_single_tool_call(block: &str, separator_tokens: &[String]) -> Option<(String, Value)> {
+fn parse_single_tool_call_v3_1(
+    block: &str,
+    separator_tokens: &[String],
+) -> Option<(String, Value)> {
     // Try each separator token
     for sep_token in separator_tokens.iter() {
         if sep_token.is_empty() {
@@ -186,7 +189,8 @@ pub fn parse_tool_calls_deepseek_v3_1(
     };
 
     // Extract individual tool call blocks
-    let blocks = extract_tool_call_blocks(trimmed, &tool_call_start_tokens, &tool_call_end_tokens);
+    let blocks =
+        extract_tool_call_blocks_v3_1(trimmed, &tool_call_start_tokens, &tool_call_end_tokens);
 
     if blocks.is_empty() {
         // Found start token but no valid blocks
@@ -196,7 +200,9 @@ pub fn parse_tool_calls_deepseek_v3_1(
     // Parse each block to extract function name and arguments
     let mut tool_calls: Vec<ToolCallResponse> = Vec::new();
     for block in blocks {
-        if let Some((function_name, arguments)) = parse_single_tool_call(&block, separator_tokens) {
+        if let Some((function_name, arguments)) =
+            parse_single_tool_call_v3_1(&block, separator_tokens)
+        {
             tool_calls.push(ToolCallResponse {
                 id: format!("call-{}", Uuid::new_v4()),
                 tp: ToolCallType::Function,

lib/parsers/src/tool_calling/json/mod.rs

@@ -2,11 +2,15 @@
 // SPDX-License-Identifier: Apache-2.0
 
 pub mod base_json_parser;
-pub mod deepseek_parser;
+pub mod deepseek_v3_1_parser;
+pub mod deepseek_v3_parser;
 
 pub use super::{config, response};
 pub use base_json_parser::{detect_tool_call_start_basic_json, try_tool_call_parse_basic_json};
-pub use deepseek_parser::{detect_tool_call_start_deepseek_v3_1, parse_tool_calls_deepseek_v3_1};
+pub use deepseek_v3_1_parser::{
+    detect_tool_call_start_deepseek_v3_1, parse_tool_calls_deepseek_v3_1,
+};
+pub use deepseek_v3_parser::{detect_tool_call_start_deepseek_v3, parse_tool_calls_deepseek_v3};
 
 pub use super::config::JsonParserConfig;
 pub use super::response::ToolCallResponse;
@@ -16,6 +20,7 @@ pub enum JsonParserType {
     // Basic is generic json parser which can handle most of the cases
     Basic,
     // Model Specific JSON Parsers
+    DeepseekV3,
     DeepseekV31,
 }
 
@@ -31,6 +36,7 @@ pub fn try_tool_call_parse_json(
 ) -> anyhow::Result<(Vec<ToolCallResponse>, Option<String>)> {
     match config.parser_type {
         JsonParserType::Basic => try_tool_call_parse_basic_json(message, config),
+        JsonParserType::DeepseekV3 => parse_tool_calls_deepseek_v3(message, config),
         JsonParserType::DeepseekV31 => parse_tool_calls_deepseek_v3_1(message, config),
     }
 }
@@ -38,6 +44,7 @@ pub fn try_tool_call_parse_json(
 pub fn detect_tool_call_start_json(chunk: &str, config: &JsonParserConfig) -> bool {
     match config.parser_type {
         JsonParserType::Basic => detect_tool_call_start_basic_json(chunk, config),
+        JsonParserType::DeepseekV3 => detect_tool_call_start_deepseek_v3(chunk, config),
         JsonParserType::DeepseekV31 => detect_tool_call_start_deepseek_v3_1(chunk, config),
     }
 }

lib/parsers/src/tool_calling/parsers.rs

@@ -30,6 +30,7 @@ pub fn get_tool_parser_map() -> &'static HashMap<&'static str, ToolCallConfig> {
         map.insert("phi4", ToolCallConfig::phi4());
         map.insert("pythonic", ToolCallConfig::pythonic());
         map.insert("harmony", ToolCallConfig::harmony());
+        map.insert("deepseek_v3", ToolCallConfig::deepseek_v3());
         map.insert("deepseek_v3_1", ToolCallConfig::deepseek_v3_1());
         map.insert("default", ToolCallConfig::default());
         map
@@ -185,6 +186,7 @@ mod tests {
             "phi4",
             "default",
             "pythonic",
+            "deepseek_v3",
             "deepseek_v3_1",
         ];
         for parser in available_parsers {
@@ -1509,6 +1511,28 @@ Remember, San Francisco weather can be quite unpredictable, particularly with it
         assert_eq!(args["unit"], "fahrenheit");
     }
 
+    #[tokio::test]
+    async fn test_deepseek_v3_parser_basic() {
+        let input = r#"<｜tool▁calls▁begin｜><｜tool▁call▁begin｜>function<｜tool▁sep｜>get_current_weather
+```json
+{"location": "Tokyo"}
+```<｜tool▁call▁end｜><｜tool▁call▁begin｜>function<｜tool▁sep｜>get_current_weather
+```json
+{"location": "Paris"}
+```<｜tool▁call▁end｜><｜tool▁calls▁end｜><｜end▁of▁sentence｜>"#;
+        let (result, content) = detect_and_parse_tool_call(input, Some("deepseek_v3"))
+            .await
+            .unwrap();
+        assert_eq!(content, Some("".to_string()));
+        assert_eq!(result.len(), 2);
+        let (name, args) = extract_name_and_args(result[0].clone());
+        assert_eq!(name, "get_current_weather");
+        assert_eq!(args["location"], "Tokyo");
+        let (name, args) = extract_name_and_args(result[1].clone());
+        assert_eq!(name, "get_current_weather");
+        assert_eq!(args["location"], "Paris");
+    }
+
     #[tokio::test]
     async fn test_deepseek_v3_1_parser_basic() {
         let input = r#"<｜tool▁calls▁begin｜><｜tool▁call▁begin｜>get_current_weather<｜tool▁sep｜>{"location": "Tokyo"}<｜tool▁call▁end｜><｜tool▁call▁begin｜>get_current_weather<｜tool▁sep｜>{"location": "Paris"}<｜tool▁call▁end｜><｜tool▁calls▁end｜><｜end▁of▁sentence｜>"#;
@@ -2412,17 +2436,38 @@ mod detect_parser_tests {
         assert!(result);
     }
 
+    // DeepSeek V3
+    #[test]
+    fn test_e2e_detect_incomplete_tool_call_start_deepseek_v3() {
+        let text = r#"<｜tool▁call▁begin｜>function<｜tool▁sep｜>get_current_weather
+```json
+{"location": "Tokyo"}
+```<｜tool▁call▁end｜>"#;
+        let result = detect_tool_call_start(text, Some("deepseek_v3")).unwrap();
+        assert!(!result);
+    }
+
+    #[test]
+    fn test_e2e_detect_tool_call_start_deepseek_v3() {
+        let text = r#"<｜tool▁calls▁begin｜><｜tool▁call▁begin｜>function<｜tool▁sep｜>get_current_weather
+```json
+{"location": "Tokyo"}
+```<｜tool▁call▁end｜>"#;
+        let result = detect_tool_call_start(text, Some("deepseek_v3")).unwrap();
+        assert!(result);
+    }
+
+    // DeepSeek V3.1
     #[test]
     fn test_e2e_detect_incomplete_tool_call_start_deepseek_v3_1() {
-        let text =
-            r#"<｜tool▁call▁begin｜>get_current_weather{"location": "Tokyo"}<｜tool▁call▁end｜>"#;
+        let text = r#"<｜tool▁call▁begin｜>get_current_weather<｜tool▁sep｜>{"location": "Tokyo"}<｜tool▁call▁end｜>"#;
         let result = detect_tool_call_start(text, Some("deepseek_v3_1")).unwrap();
         assert!(!result);
     }
 
     #[test]
     fn test_e2e_detect_tool_call_start_deepseek_v3_1() {
-        let text = r#"<｜tool▁calls▁begin｜><｜tool▁call▁begin｜>get_current_weather{"location": "Tokyo"}<｜tool▁call▁end｜>"#;
+        let text = r#"<｜tool▁calls▁begin｜><｜tool▁call▁begin｜>get_current_weather<｜tool▁sep｜>{"location": "Tokyo"}<｜tool▁call▁end｜>"#;
         let result = detect_tool_call_start(text, Some("deepseek_v3_1")).unwrap();
         assert!(result);
     }