encoding/encoding_dsv4.py
| 1 | """ |
| 2 | DeepSeek-V4 Encoding |
| 3 | |
| 4 | A self-contained implementation for encoding/decoding DeepSeek-V4 chat messages |
| 5 | with tool calling, thinking mode, and quick instruction task support. |
| 6 | """ |
| 7 | |
| 8 | from typing import Any, Dict, List, Union, Optional, Tuple |
| 9 | import copy |
| 10 | import json |
| 11 | import re |
| 12 | |
| 13 | # ============================================================ |
| 14 | # Special Tokens |
| 15 | # ============================================================ |
| 16 | |
| 17 | bos_token: str = "<|begin▁of▁sentence|>" |
| 18 | eos_token: str = "<|end▁of▁sentence|>" |
| 19 | thinking_start_token: str = "<think>" |
| 20 | thinking_end_token: str = "</think>" |
| 21 | dsml_token: str = "|DSML|" |
| 22 | |
| 23 | USER_SP_TOKEN = "<|User|>" |
| 24 | ASSISTANT_SP_TOKEN = "<|Assistant|>" |
| 25 | LATEST_REMINDER_SP_TOKEN = "<|latest_reminder|>" |
| 26 | |
| 27 | # Task special tokens for internal classification tasks |
| 28 | DS_TASK_SP_TOKENS = { |
| 29 | "action": "<|action|>", |
| 30 | "query": "<|query|>", |
| 31 | "authority": "<|authority|>", |
| 32 | "domain": "<|domain|>", |
| 33 | "title": "<|title|>", |
| 34 | "read_url": "<|read_url|>", |
| 35 | } |
| 36 | VALID_TASKS = set(DS_TASK_SP_TOKENS.keys()) |
| 37 | |
| 38 | # ============================================================ |
| 39 | # Templates |
| 40 | # ============================================================ |
| 41 | |
| 42 | system_msg_template: str = "{content}" |
| 43 | user_msg_template: str = "{content}" |
| 44 | latest_reminder_msg_template: str = "{content}" |
| 45 | assistant_msg_template: str = "{reasoning}{content}{tool_calls}" + eos_token |
| 46 | assistant_msg_wo_eos_template: str = "{reasoning}{content}{tool_calls}" |
| 47 | thinking_template: str = "{reasoning_content}" |
| 48 | |
| 49 | response_format_template: str = ( |
| 50 | "## Response Format:\n\nYou MUST strictly adhere to the following schema to reply:\n{schema}" |
| 51 | ) |
| 52 | tool_call_template: str = ( |
| 53 | "<{dsml_token}invoke name=\"{name}\">\n{arguments}\n</{dsml_token}invoke>" |
| 54 | ) |
| 55 | tool_calls_template = ( |
| 56 | "<{dsml_token}{tc_block_name}>\n{tool_calls}\n</{dsml_token}{tc_block_name}>" |
| 57 | ) |
| 58 | tool_calls_block_name: str = "tool_calls" |
| 59 | |
| 60 | tool_output_template: str = ( |
| 61 | "<tool_result>{content}</tool_result>" |
| 62 | ) |
| 63 | |
| 64 | # Reasoning effort levels. In thinking mode, the prompt for the selected level is |
| 65 | # prepended at the very beginning of the conversation. `low` is the default and |
| 66 | # adds nothing. |
| 67 | REASONING_EFFORT_PROMPTS: Dict[str, str] = { |
| 68 | "low": "", |
| 69 | "high": ( |
| 70 | "Reasoning Effort: Absolute maximum with no shortcuts permitted.\n" |
| 71 | "You MUST be very thorough in your thinking and comprehensively decompose the problem to resolve the root cause, rigorously stress-testing your logic against all potential paths, edge cases, and adversarial scenarios.\n" |
| 72 | "Explicitly write out your entire deliberation process, documenting every intermediate step, considered alternative, and rejected hypothesis to ensure absolutely no assumption is left unchecked.\n\n" |
| 73 | ), |
| 74 | "max": ( |
| 75 | "Reasoning Effort: Beyond maximum — exhaustive, relentless, and uncompromising.\n" |
| 76 | "You MUST reason with the utmost depth and rigor, leaving absolutely nothing to chance: exhaustively decompose the problem into its most fundamental components, trace every causal chain to its root, and resolve the underlying cause rather than any surface symptom.\n" |
| 77 | "Do not stop reasoning until you have independently verified the solution from multiple angles and are certain that no assumption remains unchecked and no error remains undiscovered.\n\n" |
| 78 | ), |
| 79 | } |
| 80 | DEFAULT_REASONING_EFFORT = "low" |
| 81 | |
| 82 | TOOLS_TEMPLATE = """## Tools |
| 83 | |
| 84 | You have access to a set of tools to help answer the user's question. You can invoke tools by writing a "<{dsml_token}tool_calls>" block like the following: |
| 85 | |
| 86 | <{dsml_token}tool_calls> |
| 87 | <{dsml_token}invoke name="$TOOL_NAME"> |
| 88 | <{dsml_token}parameter name="$PARAMETER_NAME" string="true|false">$PARAMETER_VALUE</{dsml_token}parameter> |
| 89 | ... |
| 90 | </{dsml_token}invoke> |
| 91 | <{dsml_token}invoke name="$TOOL_NAME2"> |
| 92 | ... |
| 93 | </{dsml_token}invoke> |
| 94 | </{dsml_token}tool_calls> |
| 95 | |
| 96 | String parameters should be specified as is and set `string="true"`. For all other types (numbers, booleans, arrays, objects), pass the value in JSON format and set `string="false"`. |
| 97 | |
| 98 | If thinking_mode is enabled (triggered by {thinking_start_token}), you MUST output your complete reasoning inside {thinking_start_token}...{thinking_end_token} BEFORE any tool calls or final response. |
| 99 | |
| 100 | Otherwise, output directly after {thinking_end_token} with tool calls or final response. |
| 101 | |
| 102 | ### Available Tool Schemas |
| 103 | |
| 104 | {tool_schemas} |
| 105 | |
| 106 | You MUST strictly follow the above defined tool name and parameter schemas to invoke tool calls. |
| 107 | """ |
| 108 | |
| 109 | # ============================================================ |
| 110 | # Utility Functions |
| 111 | # ============================================================ |
| 112 | |
| 113 | def to_json(value: Any) -> str: |
| 114 | """Serialize a value to JSON string.""" |
| 115 | try: |
| 116 | return json.dumps(value, ensure_ascii=False) |
| 117 | except: |
| 118 | return json.dumps(value, ensure_ascii=True) |
| 119 | |
| 120 | |
| 121 | def tools_from_openai_format(tools): |
| 122 | """Extract function definitions from OpenAI-format tool list.""" |
| 123 | return [tool["function"] for tool in tools] |
| 124 | |
| 125 | |
| 126 | def tool_calls_from_openai_format(tool_calls): |
| 127 | """Convert OpenAI-format tool calls to internal format.""" |
| 128 | return [ |
| 129 | { |
| 130 | "name": tool_call["function"]["name"], |
| 131 | "arguments": tool_call["function"]["arguments"], |
| 132 | } |
| 133 | for tool_call in tool_calls |
| 134 | ] |
| 135 | |
| 136 | |
| 137 | def tool_calls_to_openai_format(tool_calls): |
| 138 | """Convert internal tool calls to OpenAI format.""" |
| 139 | return [ |
| 140 | { |
| 141 | "type": "function", |
| 142 | "function": { |
| 143 | "name": tool_call["name"], |
| 144 | "arguments": tool_call["arguments"], |
| 145 | } |
| 146 | } |
| 147 | for tool_call in tool_calls |
| 148 | ] |
| 149 | |
| 150 | |
| 151 | def encode_arguments_to_dsml(tool_call: Dict[str, str]) -> str: |
| 152 | """ |
| 153 | Encode tool call arguments into DSML parameter format. |
| 154 | |
| 155 | Args: |
| 156 | tool_call: Dict with "name" and "arguments" (JSON string) keys. |
| 157 | |
| 158 | Returns: |
| 159 | DSML-formatted parameter string. |
| 160 | """ |
| 161 | p_dsml_template = '<{dsml_token}parameter name="{key}" string="{is_str}">{value}</{dsml_token}parameter>' |
| 162 | P_dsml_strs = [] |
| 163 | |
| 164 | try: |
| 165 | arguments = json.loads(tool_call["arguments"]) |
| 166 | except Exception as err: |
| 167 | arguments = {"arguments": tool_call["arguments"]} |
| 168 | |
| 169 | for k, v in arguments.items(): |
| 170 | p_dsml_str = p_dsml_template.format( |
| 171 | dsml_token=dsml_token, |
| 172 | key=k, |
| 173 | is_str="true" if isinstance(v, str) else "false", |
| 174 | value=v if isinstance(v, str) else to_json(v), |
| 175 | ) |
| 176 | P_dsml_strs.append(p_dsml_str) |
| 177 | |
| 178 | return "\n".join(P_dsml_strs) |
| 179 | |
| 180 | |
| 181 | def decode_dsml_to_arguments(tool_name: str, tool_args: Dict[str, Tuple[str, str]]) -> Dict[str, str]: |
| 182 | """ |
| 183 | Decode DSML parameters back to a tool call dict. |
| 184 | |
| 185 | Args: |
| 186 | tool_name: Name of the tool. |
| 187 | tool_args: Dict mapping param_name -> (value, is_string_flag). |
| 188 | |
| 189 | Returns: |
| 190 | Dict with "name" and "arguments" (JSON string) keys. |
| 191 | """ |
| 192 | def _decode_value(key: str, value: str, string: str): |
| 193 | if string == "true": |
| 194 | value = to_json(value) |
| 195 | return f"{to_json(key)}: {value}" |
| 196 | |
| 197 | tool_args_json = "{" + ", ".join([_decode_value(k, v, string=is_str) for k, (v, is_str) in tool_args.items()]) + "}" |
| 198 | return dict(name=tool_name, arguments=tool_args_json) |
| 199 | |
| 200 | |
| 201 | def render_tools(tools: List[Dict[str, Union[str, Dict[str, Any]]]]) -> str: |
| 202 | """ |
| 203 | Render tool schemas into the system prompt format. |
| 204 | |
| 205 | Args: |
| 206 | tools: List of tool schema dicts (each with name, description, parameters). |
| 207 | |
| 208 | Returns: |
| 209 | Formatted tools section string. |
| 210 | """ |
| 211 | tools_json = [to_json(t) for t in tools] |
| 212 | |
| 213 | return TOOLS_TEMPLATE.format( |
| 214 | tool_schemas="\n".join(tools_json), |
| 215 | dsml_token=dsml_token, |
| 216 | thinking_start_token=thinking_start_token, |
| 217 | thinking_end_token=thinking_end_token, |
| 218 | ) |
| 219 | |
| 220 | |
| 221 | def find_last_user_index(messages: List[Dict[str, Any]]) -> int: |
| 222 | """Find the index of the last user/developer message.""" |
| 223 | last_user_index = -1 |
| 224 | for idx in range(len(messages) - 1, -1, -1): |
| 225 | if messages[idx].get("role") in ["user", "developer"]: |
| 226 | last_user_index = idx |
| 227 | break |
| 228 | return last_user_index |
| 229 | |
| 230 | |
| 231 | # ============================================================ |
| 232 | # Message Rendering |
| 233 | # ============================================================ |
| 234 | |
| 235 | def render_message(index: int, messages: List[Dict[str, Any]], thinking_mode: str, drop_thinking: bool = True, reasoning_effort: Optional[str] = None) -> str: |
| 236 | """ |
| 237 | Render a single message at the given index into its encoded string form. |
| 238 | |
| 239 | This is the core function that converts each message in the conversation |
| 240 | into the DeepSeek-V4 format. |
| 241 | |
| 242 | Args: |
| 243 | index: Index of the message to render. |
| 244 | messages: Full list of messages in the conversation. |
| 245 | thinking_mode: Either "chat" or "thinking". |
| 246 | drop_thinking: Whether to drop reasoning content from earlier turns. |
| 247 | reasoning_effort: Reasoning effort level, one of "low", "high", "max". |
| 248 | None is treated as "low". |
| 249 | |
| 250 | Returns: |
| 251 | Encoded string for this message. |
| 252 | """ |
| 253 | assert 0 <= index < len(messages) |
| 254 | assert thinking_mode in ["chat", "thinking"], f"Invalid thinking_mode `{thinking_mode}`" |
| 255 | |
| 256 | prompt = "" |
| 257 | msg = messages[index] |
| 258 | last_user_idx = find_last_user_index(messages) |
| 259 | |
| 260 | role = msg.get("role") |
| 261 | content = msg.get("content") |
| 262 | tools = msg.get("tools") |
| 263 | response_format = msg.get("response_format") |
| 264 | tool_calls = msg.get("tool_calls") |
| 265 | reasoning_content = msg.get("reasoning_content") |
| 266 | wo_eos = msg.get("wo_eos", False) |
| 267 | |
| 268 | if tools: |
| 269 | tools = tools_from_openai_format(tools) |
| 270 | if tool_calls: |
| 271 | tool_calls = tool_calls_from_openai_format(tool_calls) |
| 272 | |
| 273 | # Reasoning effort prefix (only at index 0 in thinking mode; "low" adds nothing) |
| 274 | reasoning_effort = reasoning_effort or DEFAULT_REASONING_EFFORT |
| 275 | assert reasoning_effort in REASONING_EFFORT_PROMPTS, \ |
| 276 | f"Invalid reasoning effort: {reasoning_effort}, expected one of {list(REASONING_EFFORT_PROMPTS)}" |
| 277 | if index == 0 and thinking_mode == "thinking": |
| 278 | prompt += REASONING_EFFORT_PROMPTS[reasoning_effort] |
| 279 | |
| 280 | if role == "system": |
| 281 | prompt += system_msg_template.format(content=content or "") |
| 282 | if tools: |
| 283 | prompt += "\n\n" + render_tools(tools) |
| 284 | if response_format: |
| 285 | prompt += "\n\n" + response_format_template.format(schema=to_json(response_format)) |
| 286 | |
| 287 | elif role == "developer": |
| 288 | assert content, f"Invalid message for role `{role}`: {msg}" |
| 289 | |
| 290 | content_developer = USER_SP_TOKEN |
| 291 | content_developer += content |
| 292 | |
| 293 | if tools: |
| 294 | content_developer += "\n\n" + render_tools(tools) |
| 295 | if response_format: |
| 296 | content_developer += "\n\n" + response_format_template.format(schema=to_json(response_format)) |
| 297 | |
| 298 | prompt += user_msg_template.format(content=content_developer) |
| 299 | |
| 300 | elif role == "user": |
| 301 | prompt += USER_SP_TOKEN |
| 302 | |
| 303 | # Handle content blocks (tool results mixed with text) |
| 304 | content_blocks = msg.get("content_blocks") |
| 305 | if content_blocks: |
| 306 | parts = [] |
| 307 | for block in content_blocks: |
| 308 | block_type = block.get("type") |
| 309 | if block_type == "text": |
| 310 | parts.append(block.get("text", "")) |
| 311 | elif block_type == "tool_result": |
| 312 | tool_content = block.get("content", "") |
| 313 | if isinstance(tool_content, list): |
| 314 | text_parts = [] |
| 315 | for b in tool_content: |
| 316 | if b.get("type") == "text": |
| 317 | text_parts.append(b.get("text", "")) |
| 318 | else: |
| 319 | text_parts.append(f"[Unsupported {b.get('type')}]") |
| 320 | tool_content = "\n\n".join(text_parts) |
| 321 | parts.append(tool_output_template.format(content=tool_content)) |
| 322 | else: |
| 323 | parts.append(f"[Unsupported {block_type}]") |
| 324 | prompt += "\n\n".join(parts) |
| 325 | else: |
| 326 | prompt += content or "" |
| 327 | |
| 328 | elif role == "latest_reminder": |
| 329 | prompt += LATEST_REMINDER_SP_TOKEN + latest_reminder_msg_template.format(content=content) |
| 330 | |
| 331 | elif role == "tool": |
| 332 | raise NotImplementedError("deepseek_v4 merges tool messages into user; please preprocess with merge_tool_messages()") |
| 333 | |
| 334 | elif role == "assistant": |
| 335 | thinking_part = "" |
| 336 | tc_content = "" |
| 337 | |
| 338 | if tool_calls: |
| 339 | tc_list = [ |
| 340 | tool_call_template.format( |
| 341 | dsml_token=dsml_token, |
| 342 | name=tc.get("name"), |
| 343 | arguments=encode_arguments_to_dsml(tc) |
| 344 | ) |
| 345 | for tc in tool_calls |
| 346 | ] |
| 347 | tc_content += '\n\n' + tool_calls_template.format( |
| 348 | dsml_token=dsml_token, |
| 349 | tool_calls="\n".join(tc_list), |
| 350 | tc_block_name=tool_calls_block_name, |
| 351 | ) |
| 352 | |
| 353 | summary_content = content or "" |
| 354 | rc = reasoning_content or "" |
| 355 | |
| 356 | # Check if previous message has a task - if so, this is a task output (no thinking) |
| 357 | prev_has_task = index - 1 >= 0 and messages[index - 1].get("task") is not None |
| 358 | |
| 359 | if thinking_mode == "thinking" and not prev_has_task: |
| 360 | if not drop_thinking or index > last_user_idx: |
| 361 | thinking_part = thinking_template.format(reasoning_content=rc) + thinking_end_token |
| 362 | else: |
| 363 | thinking_part = "" |
| 364 | |
| 365 | if wo_eos: |
| 366 | prompt += assistant_msg_wo_eos_template.format( |
| 367 | reasoning=thinking_part, |
| 368 | content=summary_content, |
| 369 | tool_calls=tc_content, |
| 370 | ) |
| 371 | else: |
| 372 | prompt += assistant_msg_template.format( |
| 373 | reasoning=thinking_part, |
| 374 | content=summary_content, |
| 375 | tool_calls=tc_content, |
| 376 | ) |
| 377 | else: |
| 378 | raise NotImplementedError(f"Unknown role: {role}") |
| 379 | |
| 380 | # Append transition tokens based on what follows |
| 381 | if index + 1 < len(messages) and messages[index + 1].get("role") not in ["assistant", "latest_reminder"]: |
| 382 | return prompt |
| 383 | |
| 384 | task = messages[index].get("task") |
| 385 | if task is not None: |
| 386 | # Task special token for internal classification tasks |
| 387 | assert task in VALID_TASKS, f"Invalid task: '{task}'. Valid tasks are: {list(VALID_TASKS)}" |
| 388 | task_sp_token = DS_TASK_SP_TOKENS[task] |
| 389 | |
| 390 | if task != "action": |
| 391 | # Non-action tasks: append task sp token directly after the message |
| 392 | prompt += task_sp_token |
| 393 | else: |
| 394 | # Action task: append Assistant + thinking token + action sp token |
| 395 | prompt += ASSISTANT_SP_TOKEN |
| 396 | prompt += thinking_end_token if thinking_mode != "thinking" else thinking_start_token |
| 397 | prompt += task_sp_token |
| 398 | |
| 399 | elif messages[index].get("role") in ["user", "developer"]: |
| 400 | # Normal generation: append Assistant + thinking token |
| 401 | prompt += ASSISTANT_SP_TOKEN |
| 402 | if not drop_thinking and thinking_mode == "thinking": |
| 403 | prompt += thinking_start_token |
| 404 | elif drop_thinking and thinking_mode == "thinking" and index >= last_user_idx: |
| 405 | prompt += thinking_start_token |
| 406 | else: |
| 407 | prompt += thinking_end_token |
| 408 | |
| 409 | return prompt |
| 410 | |
| 411 | |
| 412 | # ============================================================ |
| 413 | # Preprocessing |
| 414 | # ============================================================ |
| 415 | |
| 416 | def merge_tool_messages(messages: List[Dict[str, Any]]) -> List[Dict[str, Any]]: |
| 417 | """ |
| 418 | Merge tool messages into the preceding user message using content_blocks format. |
| 419 | |
| 420 | DeepSeek-V4 does not have a standalone "tool" role; instead, tool results |
| 421 | are encoded as <tool_result> blocks within user messages. |
| 422 | |
| 423 | This function converts a standard OpenAI-format conversation (with separate |
| 424 | "tool" role messages) into V4 format where tool results are merged into |
| 425 | user messages. |
| 426 | |
| 427 | Args: |
| 428 | messages: List of message dicts in OpenAI format. |
| 429 | |
| 430 | Returns: |
| 431 | Processed message list with tool messages merged into user messages. |
| 432 | """ |
| 433 | merged: List[Dict[str, Any]] = [] |
| 434 | |
| 435 | for msg in messages: |
| 436 | msg = copy.deepcopy(msg) |
| 437 | role = msg.get("role") |
| 438 | |
| 439 | if role == "tool": |
| 440 | # Convert tool message to a user message with tool_result block |
| 441 | tool_block = { |
| 442 | "type": "tool_result", |
| 443 | "tool_use_id": msg.get("tool_call_id", ""), |
| 444 | "content": msg.get("content", ""), |
| 445 | } |
| 446 | # Merge into previous message if it's already a user (merged tool) |
| 447 | if merged and merged[-1].get("role") == "user" and "content_blocks" in merged[-1]: |
| 448 | merged[-1]["content_blocks"].append(tool_block) |
| 449 | else: |
| 450 | merged.append({ |
| 451 | "role": "user", |
| 452 | "content_blocks": [tool_block], |
| 453 | }) |
| 454 | elif role == "user": |
| 455 | text_block = {"type": "text", "text": msg.get("content", "")} |
| 456 | if merged and merged[-1].get("role") == "user" and "content_blocks" in merged[-1] and merged[-1].get("task") is None: |
| 457 | merged[-1]["content_blocks"].append(text_block) |
| 458 | else: |
| 459 | new_msg = { |
| 460 | "role": "user", |
| 461 | "content": msg.get("content", ""), |
| 462 | "content_blocks": [text_block], |
| 463 | } |
| 464 | # Preserve extra fields (task, wo_eos, mask, etc.) |
| 465 | for key in ("task", "wo_eos", "mask"): |
| 466 | if key in msg: |
| 467 | new_msg[key] = msg[key] |
| 468 | merged.append(new_msg) |
| 469 | else: |
| 470 | merged.append(msg) |
| 471 | |
| 472 | return merged |
| 473 | |
| 474 | |
| 475 | def sort_tool_results_by_call_order(messages: List[Dict[str, Any]]) -> List[Dict[str, Any]]: |
| 476 | """ |
| 477 | Sort tool_result blocks within user messages by the order of tool_calls |
| 478 | in the preceding assistant message. |
| 479 | |
| 480 | Args: |
| 481 | messages: Preprocessed message list (after merge_tool_messages). |
| 482 | |
| 483 | Returns: |
| 484 | Message list with sorted tool result blocks. |
| 485 | """ |
| 486 | last_tool_call_order: Dict[str, int] = {} |
| 487 | |
| 488 | for msg in messages: |
| 489 | role = msg.get("role") |
| 490 | if role == "assistant" and msg.get("tool_calls"): |
| 491 | last_tool_call_order = {} |
| 492 | for idx, tc in enumerate(msg["tool_calls"]): |
| 493 | tc_id = tc.get("id") or tc.get("function", {}).get("id", "") |
| 494 | if tc_id: |
| 495 | last_tool_call_order[tc_id] = idx |
| 496 | |
| 497 | elif role == "user" and msg.get("content_blocks"): |
| 498 | tool_blocks = [b for b in msg["content_blocks"] if b.get("type") == "tool_result"] |
| 499 | if len(tool_blocks) > 1 and last_tool_call_order: |
| 500 | sorted_blocks = sorted( |
| 501 | tool_blocks, |
| 502 | key=lambda b: last_tool_call_order.get(b.get("tool_use_id", ""), 0) |
| 503 | ) |
| 504 | sorted_idx = 0 |
| 505 | new_blocks = [] |
| 506 | for block in msg["content_blocks"]: |
| 507 | if block.get("type") == "tool_result": |
| 508 | new_blocks.append(sorted_blocks[sorted_idx]) |
| 509 | sorted_idx += 1 |
| 510 | else: |
| 511 | new_blocks.append(block) |
| 512 | msg["content_blocks"] = new_blocks |
| 513 | |
| 514 | return messages |
| 515 | |
| 516 | |
| 517 | # ============================================================ |
| 518 | # Main Encoding Function |
| 519 | # ============================================================ |
| 520 | |
| 521 | def encode_messages( |
| 522 | messages: List[Dict[str, Any]], |
| 523 | thinking_mode: str, |
| 524 | context: Optional[List[Dict[str, Any]]] = None, |
| 525 | drop_thinking: bool = True, |
| 526 | add_default_bos_token: bool = True, |
| 527 | reasoning_effort: Optional[str] = None, |
| 528 | ) -> str: |
| 529 | """ |
| 530 | Encode a list of messages into the DeepSeek-V4 prompt format. |
| 531 | |
| 532 | This is the main entry point for encoding conversations. It handles: |
| 533 | - BOS token insertion |
| 534 | - Thinking mode with optional reasoning content dropping |
| 535 | - Tool message merging into user messages |
| 536 | - Multi-turn conversation context |
| 537 | |
| 538 | Args: |
| 539 | messages: List of message dicts to encode. |
| 540 | thinking_mode: Either "chat" or "thinking". |
| 541 | context: Optional preceding context messages (already encoded prefix). |
| 542 | drop_thinking: If True, drop reasoning_content from earlier assistant turns |
| 543 | (only keep reasoning for messages after the last user message). |
| 544 | add_default_bos_token: Whether to prepend BOS token at conversation start. |
| 545 | reasoning_effort: Reasoning effort level, one of "low", "high", "max". |
| 546 | Only takes effect in thinking mode. None is treated as "low". |
| 547 | |
| 548 | Returns: |
| 549 | The encoded prompt string. |
| 550 | """ |
| 551 | context = context if context else [] |
| 552 | |
| 553 | # Preprocess: merge tool messages and sort tool results |
| 554 | messages = merge_tool_messages(messages) |
| 555 | messages = sort_tool_results_by_call_order(context + messages)[len(context):] |
| 556 | if context: |
| 557 | context = merge_tool_messages(context) |
| 558 | context = sort_tool_results_by_call_order(context) |
| 559 | |
| 560 | full_messages = context + messages |
| 561 | |
| 562 | prompt = bos_token if add_default_bos_token and len(context) == 0 else "" |
| 563 | |
| 564 | # Resolve drop_thinking: if any message has tools defined, don't drop thinking |
| 565 | effective_drop_thinking = drop_thinking |
| 566 | if any(m.get("tools") for m in full_messages): |
| 567 | effective_drop_thinking = False |
| 568 | |
| 569 | if thinking_mode == "thinking" and effective_drop_thinking: |
| 570 | full_messages = _drop_thinking_messages(full_messages) |
| 571 | # After dropping, recalculate how many messages to render |
| 572 | # (context may have shrunk too) |
| 573 | num_to_render = len(full_messages) - len(_drop_thinking_messages(context)) |
| 574 | context_len = len(full_messages) - num_to_render |
| 575 | else: |
| 576 | num_to_render = len(messages) |
| 577 | context_len = len(context) |
| 578 | |
| 579 | for idx in range(num_to_render): |
| 580 | prompt += render_message( |
| 581 | idx + context_len, |
| 582 | full_messages, |
| 583 | thinking_mode=thinking_mode, |
| 584 | drop_thinking=effective_drop_thinking, |
| 585 | reasoning_effort=reasoning_effort, |
| 586 | ) |
| 587 | |
| 588 | return prompt |
| 589 | |
| 590 | |
| 591 | def _drop_thinking_messages(messages: List[Dict[str, Any]]) -> List[Dict[str, Any]]: |
| 592 | """ |
| 593 | Drop reasoning_content and non-essential messages before the last user message. |
| 594 | |
| 595 | Behavior: |
| 596 | - Messages with role in ["user", "system", "tool", "latest_reminder"] are always kept. |
| 597 | - Messages at or after the last user index are always kept. |
| 598 | - Assistant messages before the last user get reasoning_content removed. |
| 599 | - Developer messages before the last user are dropped entirely. |
| 600 | """ |
| 601 | last_user_idx = find_last_user_index(messages) |
| 602 | result = [] |
| 603 | keep_roles = {"user", "system", "tool", "latest_reminder", "direct_search_results"} |
| 604 | |
| 605 | for idx, msg in enumerate(messages): |
| 606 | role = msg.get("role") |
| 607 | if role in keep_roles or idx >= last_user_idx: |
| 608 | result.append(msg) |
| 609 | elif role == "assistant": |
| 610 | msg = copy.copy(msg) |
| 611 | msg.pop("reasoning_content", None) |
| 612 | result.append(msg) |
| 613 | # developer and other roles before last_user_idx are dropped |
| 614 | |
| 615 | return result |
| 616 | |
| 617 | |
| 618 | # ============================================================ |
| 619 | # Parsing (Decoding model output) |
| 620 | # ============================================================ |
| 621 | |
| 622 | def _read_until_stop(index: int, text: str, stop: List[str]) -> Tuple[int, str, Optional[str]]: |
| 623 | """ |
| 624 | Read text from index until one of the stop strings is found. |
| 625 | |
| 626 | Returns: |
| 627 | Tuple of (new_index, content_before_stop, matched_stop_string_or_None). |
| 628 | """ |
| 629 | min_pos = len(text) |
| 630 | matched_stop = None |
| 631 | |
| 632 | for s in stop: |
| 633 | pos = text.find(s, index) |
| 634 | if pos != -1 and pos < min_pos: |
| 635 | min_pos = pos |
| 636 | matched_stop = s |
| 637 | |
| 638 | if matched_stop: |
| 639 | content = text[index:min_pos] |
| 640 | return min_pos + len(matched_stop), content, matched_stop |
| 641 | else: |
| 642 | content = text[index:] |
| 643 | return len(text), content, None |
| 644 | |
| 645 | |
| 646 | def parse_tool_calls(index: int, text: str) -> Tuple[int, Optional[str], List[Dict[str, str]]]: |
| 647 | """ |
| 648 | Parse DSML tool calls from text starting at the given index. |
| 649 | |
| 650 | Args: |
| 651 | index: Starting position in text. |
| 652 | text: The full text to parse. |
| 653 | |
| 654 | Returns: |
| 655 | Tuple of (new_index, last_stop_token, list_of_tool_call_dicts). |
| 656 | Each tool call dict has "name" and "arguments" keys. |
| 657 | """ |
| 658 | tool_calls: List[Dict[str, Any]] = [] |
| 659 | stop_token = None |
| 660 | tool_calls_end_token = f"</{dsml_token}{tool_calls_block_name}>" |
| 661 | |
| 662 | while index < len(text): |
| 663 | index, _, stop_token = _read_until_stop(index, text, [f"<{dsml_token}invoke", tool_calls_end_token]) |
| 664 | if _ != ">\n": |
| 665 | raise ValueError(f"Tool call format error: expected '>\\n' but got '{_}'") |
| 666 | |
| 667 | if stop_token == tool_calls_end_token: |
| 668 | break |
| 669 | |
| 670 | if stop_token is None: |
| 671 | raise ValueError("Missing special token in tool calls") |
| 672 | |
| 673 | index, tool_name_content, stop_token = _read_until_stop(index, text, [f"<{dsml_token}parameter", f"</{dsml_token}invoke"]) |
| 674 | |
| 675 | p_tool_name = re.findall(r'^\s*name="(.*?)">\n$', tool_name_content, flags=re.DOTALL) |
| 676 | if len(p_tool_name) != 1: |
| 677 | raise ValueError(f"Tool name format error: '{tool_name_content}'") |
| 678 | tool_name = p_tool_name[0] |
| 679 | |
| 680 | tool_args: Dict[str, Tuple[str, str]] = {} |
| 681 | while stop_token == f"<{dsml_token}parameter": |
| 682 | index, param_content, stop_token = _read_until_stop(index, text, [f"/{dsml_token}parameter"]) |
| 683 | |
| 684 | param_kv = re.findall(r'^ name="(.*?)" string="(true|false)">(.*?)<$', param_content, flags=re.DOTALL) |
| 685 | if len(param_kv) != 1: |
| 686 | raise ValueError(f"Parameter format error: '{param_content}'") |
| 687 | param_name, string, param_value = param_kv[0] |
| 688 | |
| 689 | if param_name in tool_args: |
| 690 | raise ValueError(f"Duplicate parameter name: '{param_name}'") |
| 691 | tool_args[param_name] = (param_value, string) |
| 692 | |
| 693 | index, content, stop_token = _read_until_stop(index, text, [f"<{dsml_token}parameter", f"</{dsml_token}invoke"]) |
| 694 | if content != ">\n": |
| 695 | raise ValueError(f"Parameter format error: expected '>\\n' but got '{content}'") |
| 696 | |
| 697 | tool_call = decode_dsml_to_arguments(tool_name=tool_name, tool_args=tool_args) |
| 698 | tool_calls.append(tool_call) |
| 699 | |
| 700 | return index, stop_token, tool_calls |
| 701 | |
| 702 | |
| 703 | def parse_message_from_completion_text(text: str, thinking_mode: str) -> Dict[str, Any]: |
| 704 | """ |
| 705 | Parse a model completion text into a structured assistant message. |
| 706 | |
| 707 | This function takes the raw text output from the model (a single assistant turn) |
| 708 | and extracts: |
| 709 | - reasoning_content (thinking block) |
| 710 | - content (summary/response) |
| 711 | - tool_calls (if any) |
| 712 | |
| 713 | NOTE: This function is designed to parse only correctly formatted strings and |
| 714 | will raise ValueError for malformed output. |
| 715 | |
| 716 | Args: |
| 717 | text: The raw completion text (including EOS token). |
| 718 | thinking_mode: Either "chat" or "thinking". |
| 719 | |
| 720 | Returns: |
| 721 | Dict with keys: "role", "content", "reasoning_content", "tool_calls". |
| 722 | tool_calls are in OpenAI format. |
| 723 | """ |
| 724 | summary_content, reasoning_content, tool_calls = "", "", [] |
| 725 | index, stop_token = 0, None |
| 726 | tool_calls_start_token = f"\n\n<{dsml_token}{tool_calls_block_name}" |
| 727 | |
| 728 | is_thinking = thinking_mode == "thinking" |
| 729 | is_tool_calling = False |
| 730 | |
| 731 | if is_thinking: |
| 732 | index, content_delta, stop_token = _read_until_stop(index, text, [thinking_end_token, tool_calls_start_token]) |
| 733 | reasoning_content = content_delta |
| 734 | assert stop_token == thinking_end_token, "Invalid thinking format: missing </think>" |
| 735 | |
| 736 | index, content_delta, stop_token = _read_until_stop(index, text, [eos_token, tool_calls_start_token]) |
| 737 | summary_content = content_delta |
| 738 | if stop_token == tool_calls_start_token: |
| 739 | is_tool_calling = True |
| 740 | else: |
| 741 | assert stop_token == eos_token, "Invalid format: missing EOS token" |
| 742 | |
| 743 | if is_tool_calling: |
| 744 | index, stop_token, tool_calls = parse_tool_calls(index, text) |
| 745 | |
| 746 | index, tool_ends_text, stop_token = _read_until_stop(index, text, [eos_token]) |
| 747 | assert not tool_ends_text, "Unexpected content after tool calls" |
| 748 | |
| 749 | assert len(text) == index and stop_token in [eos_token, None], "Unexpected content at end" |
| 750 | |
| 751 | for sp_token in [bos_token, eos_token, thinking_start_token, thinking_end_token, dsml_token]: |
| 752 | assert sp_token not in summary_content and sp_token not in reasoning_content, \ |
| 753 | f"Unexpected special token '{sp_token}' in content" |
| 754 | |
| 755 | return { |
| 756 | "role": "assistant", |
| 757 | "content": summary_content, |
| 758 | "reasoning_content": reasoning_content, |
| 759 | "tool_calls": tool_calls_to_openai_format(tool_calls) |
| 760 | } |
| 761 | |