[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_server.c

```c
if (**p != '}') {
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            goto fail;
        }
        (*p)++;

        const char *t = type ? type : "message";
        /* Replayed items must be in a terminal "completed" state. in_progress,
         * incomplete, and failed all represent partial model state the client
         * never confirmed — feeding them back as history would let DS4 continue
         * from a tool action that never finished. Reject explicitly. */
        if (status_str && status_str[0] &&
            strcmp(status_str, "completed") != 0)
        {
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            buf_free(&pending_reasoning);
            return false;
        }
        /* Three classes of items:
         *   1. consumes_reasoning: assistant message / function_call / hosted-tool
         *      call. Attaches pending reasoning to its own assistant message.
         *   2. is_bookkeeping: compaction / context_compaction etc. Semantically
         *      transparent — passes through without touching pending_reasoning.
         *   3. everything else (user message, tool output): forces pending
         *      reasoning to flush in-position as an empty assistant message so it
         *      stays before this item in the rendered history. */
        bool consumes_reasoning =
            (!strcmp(t, "message") && role && !strcmp(role, "assistant")) ||
            !strcmp(t, "function_call") || !strcmp(t, "custom_tool_call") ||
            !strcmp(t, "local_shell_call") || !strcmp(t, "web_search_call") ||
            !strcmp(t, "tool_search_call") || !strcmp(t, "image_generation_call");
        bool is_bookkeeping =
            !strcmp(t, "compaction") || !strcmp(t, "context_compaction");
        if (!consumes_reasoning && !is_bookkeeping && pending_reasoning.len) {
            chat_msg flush_msg = {0};
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_server.c

```c
if (**p != '}') {
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            goto fail;
        }
        (*p)++;

        const char *t = type ? type : "message";
        /* Replayed items must be in a terminal "completed" state. in_progress,
         * incomplete, and failed all represent partial model state the client
         * never confirmed — feeding them back as history would let DS4 continue
         * from a tool action that never finished. Reject explicitly. */
        if (status_str && status_str[0] &&
            strcmp(status_str, "completed") != 0)
        {
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            buf_free(&pending_reasoning);
            return false;
        }
        /* Three classes of items:
         *   1. consumes_reasoning: assistant message / function_call / hosted-tool
         *      call. Attaches pending reasoning to its own assistant message.
         *   2. is_bookkeeping: compaction / context_compaction etc. Semantically
         *      transparent — passes through without touching pending_reasoning.
         *   3. everything else (user message, tool output): forces pending
         *      reasoning to flush in-position as an empty assistant message so it
         *      stays before this item in the rendered history. */
        bool consumes_reasoning =
            (!strcmp(t, "message") && role && !strcmp(role, "assistant")) ||
            !strcmp(t, "function_call") || !strcmp(t, "custom_tool_call") ||
            !strcmp(t, "local_shell_call") || !strcmp(t, "web_search_call") ||
            !strcmp(t, "tool_search_call") || !strcmp(t, "image_generation_call");
        bool is_bookkeeping =
            !strcmp(t, "compaction") || !strcmp(t, "context_compaction");
        if (!consumes_reasoning && !is_bookkeeping && pending_reasoning.len) {
            chat_msg flush_msg = {0};
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
!strcmp(t, "compaction") || !strcmp(t, "context_compaction");
        if (!consumes_reasoning && !is_bookkeeping && pending_reasoning.len) {
            chat_msg flush_msg = {0};
            flush_msg.role = xstrdup("assistant");
            flush_msg.content = xstrdup("");
            flush_msg.reasoning = buf_take(&pending_reasoning);
            chat_msgs_push(msgs, flush_msg);
        }
        if (!strcmp(t, "message")) {
            chat_msg msg = {0};
            msg.role = xstrdup(role ? role : "user");
            msg.content = content ? content : xstrdup("");
            content = NULL;
            if (!strcmp(msg.role, "assistant") && pending_reasoning.len) {
                msg.reasoning = buf_take(&pending_reasoning);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "function_call") || !strcmp(t, "custom_tool_call")) {
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            /* function_call uses `arguments` (JSON string); custom_tool_call uses
             * `input` (free text). Treat both as the same on-wire argument blob —
             * append_dsml_arguments_from_json will fall back to a single text param
             * if the value isn't a JSON object. */
            const char *args_src = arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            if (strcmp(t, "custom_tool_call") && namespace && namespace[0] &&
                name && name[0])
            {
                buf qualified = {0};
                buf_puts(&qualified, namespace);
                buf_puts(&qualified, name);
                tc.name = buf_take(&qualified);
            } else {
                tc.name = xstrdup(name ? name : "");
            }
            /* A Responses turn that has both message text and tool calls splits
             * them across separate output items; the chat template renders the
             * second assistant record without an `<|Assistant|>` prefix, leaving
             * the tool call bare. Merge into the previous assistant message
             * when nothing user-like / tool-output-like came between them. */
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
!strcmp(t, "compaction") || !strcmp(t, "context_compaction");
        if (!consumes_reasoning && !is_bookkeeping && pending_reasoning.len) {
            chat_msg flush_msg = {0};
            flush_msg.role = xstrdup("assistant");
            flush_msg.content = xstrdup("");
            flush_msg.reasoning = buf_take(&pending_reasoning);
            chat_msgs_push(msgs, flush_msg);
        }
        if (!strcmp(t, "message")) {
            chat_msg msg = {0};
            msg.role = xstrdup(role ? role : "user");
            msg.content = content ? content : xstrdup("");
            content = NULL;
            if (!strcmp(msg.role, "assistant") && pending_reasoning.len) {
                msg.reasoning = buf_take(&pending_reasoning);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "function_call") || !strcmp(t, "custom_tool_call")) {
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            /* function_call uses `arguments` (JSON string); custom_tool_call uses
             * `input` (free text). Treat both as the same on-wire argument blob —
             * append_dsml_arguments_from_json will fall back to a single text param
             * if the value isn't a JSON object. */
            const char *args_src = arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            if (strcmp(t, "custom_tool_call") && namespace && namespace[0] &&
                name && name[0])
            {
                buf qualified = {0};
                buf_puts(&qualified, namespace);
                buf_puts(&qualified, name);
                tc.name = buf_take(&qualified);
            } else {
                tc.name = xstrdup(name ? name : "");
            }
            /* A Responses turn that has both message text and tool calls splits
             * them across separate output items; the chat template renders the
             * second assistant record without an `<|Assistant|>` prefix, leaving
             * the tool call bare. Merge into the previous assistant message
             * when nothing user-like / tool-output-like came between them. */
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
!strcmp(t, "compaction") || !strcmp(t, "context_compaction");
        if (!consumes_reasoning && !is_bookkeeping && pending_reasoning.len) {
            chat_msg flush_msg = {0};
            flush_msg.role = xstrdup("assistant");
            flush_msg.content = xstrdup("");
            flush_msg.reasoning = buf_take(&pending_reasoning);
            chat_msgs_push(msgs, flush_msg);
        }
        if (!strcmp(t, "message")) {
            chat_msg msg = {0};
            msg.role = xstrdup(role ? role : "user");
            msg.content = content ? content : xstrdup("");
            content = NULL;
            if (!strcmp(msg.role, "assistant") && pending_reasoning.len) {
                msg.reasoning = buf_take(&pending_reasoning);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "function_call") || !strcmp(t, "custom_tool_call")) {
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            /* function_call uses `arguments` (JSON string); custom_tool_call uses
             * `input` (free text). Treat both as the same on-wire argument blob —
             * append_dsml_arguments_from_json will fall back to a single text param
             * if the value isn't a JSON object. */
            const char *args_src = arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            if (strcmp(t, "custom_tool_call") && namespace && namespace[0] &&
                name && name[0])
            {
                buf qualified = {0};
                buf_puts(&qualified, namespace);
                buf_puts(&qualified, name);
                tc.name = buf_take(&qualified);
            } else {
                tc.name = xstrdup(name ? name : "");
            }
            /* A Responses turn that has both message text and tool calls splits
             * them across separate output items; the chat template renders the
             * second assistant record without an `<|Assistant|>` prefix, leaving
             * the tool call bare. Merge into the previous assistant message
             * when nothing user-like / tool-output-like came between them. */
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
!strcmp(t, "compaction") || !strcmp(t, "context_compaction");
        if (!consumes_reasoning && !is_bookkeeping && pending_reasoning.len) {
            chat_msg flush_msg = {0};
            flush_msg.role = xstrdup("assistant");
            flush_msg.content = xstrdup("");
            flush_msg.reasoning = buf_take(&pending_reasoning);
            chat_msgs_push(msgs, flush_msg);
        }
        if (!strcmp(t, "message")) {
            chat_msg msg = {0};
            msg.role = xstrdup(role ? role : "user");
            msg.content = content ? content : xstrdup("");
            content = NULL;
            if (!strcmp(msg.role, "assistant") && pending_reasoning.len) {
                msg.reasoning = buf_take(&pending_reasoning);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "function_call") || !strcmp(t, "custom_tool_call")) {
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            /* function_call uses `arguments` (JSON string); custom_tool_call uses
             * `input` (free text). Treat both as the same on-wire argument blob —
             * append_dsml_arguments_from_json will fall back to a single text param
             * if the value isn't a JSON object. */
            const char *args_src = arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            if (strcmp(t, "custom_tool_call") && namespace && namespace[0] &&
                name && name[0])
            {
                buf qualified = {0};
                buf_puts(&qualified, namespace);
                buf_puts(&qualified, name);
                tc.name = buf_take(&qualified);
            } else {
                tc.name = xstrdup(name ? name : "");
            }
            /* A Responses turn that has both message text and tool calls splits
             * them across separate output items; the chat template renders the
             * second assistant record without an `<|Assistant|>` prefix, leaving
             * the tool call bare. Merge into the previous assistant message
             * when nothing user-like / tool-output-like came between them. */
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "function_call_output") || !strcmp(t, "custom_tool_call_output")) {
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            msg.content = output ? output : xstrdup("");
            output = NULL;
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "reasoning")) {
            /* Stash so it merges into the next assistant message. summary is the
             * short-form list, content is the verbose chain. Either can be empty. */
            if (summary && summary[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, summary);
            }
            if (content && content[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, content);
            }
        } else if (!strcmp(t, "local_shell_call") || !strcmp(t, "web_search_call") ||
                   !strcmp(t, "tool_search_call") || !strcmp(t, "image_generation_call"))
        {
            /* Hosted-tool history isn't natively supported (DS4 doesn't register
             * these tools), but a Codex client may still replay them when the
             * model used them in a prior turn. Surface them as function_call
             * shaped history so the next prompt retains the action that ran. */
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            if (!strcmp(t, "tool_search_call")) {
                tc.name = xstrdup("tool_search");
            } else if (!strcmp(t, "local_shell_call")) {
                tc.name = xstrdup("local_shell");
            } else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "function_call_output") || !strcmp(t, "custom_tool_call_output")) {
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            msg.content = output ? output : xstrdup("");
            output = NULL;
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "reasoning")) {
            /* Stash so it merges into the next assistant message. summary is the
             * short-form list, content is the verbose chain. Either can be empty. */
            if (summary && summary[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, summary);
            }
            if (content && content[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, content);
            }
        } else if (!strcmp(t, "local_shell_call") || !strcmp(t, "web_search_call") ||
                   !strcmp(t, "tool_search_call") || !strcmp(t, "image_generation_call"))
        {
            /* Hosted-tool history isn't natively supported (DS4 doesn't register
             * these tools), but a Codex client may still replay them when the
             * model used them in a prior turn. Surface them as function_call
             * shaped history so the next prompt retains the action that ran. */
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            if (!strcmp(t, "tool_search_call")) {
                tc.name = xstrdup("tool_search");
            } else if (!strcmp(t, "local_shell_call")) {
                tc.name = xstrdup("local_shell");
            } else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "function_call_output") || !strcmp(t, "custom_tool_call_output")) {
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            msg.content = output ? output : xstrdup("");
            output = NULL;
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "reasoning")) {
            /* Stash so it merges into the next assistant message. summary is the
             * short-form list, content is the verbose chain. Either can be empty. */
            if (summary && summary[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, summary);
            }
            if (content && content[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, content);
            }
        } else if (!strcmp(t, "local_shell_call") || !strcmp(t, "web_search_call") ||
                   !strcmp(t, "tool_search_call") || !strcmp(t, "image_generation_call"))
        {
            /* Hosted-tool history isn't natively supported (DS4 doesn't register
             * these tools), but a Codex client may still replay them when the
             * model used them in a prior turn. Surface them as function_call
             * shaped history so the next prompt retains the action that ran. */
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            if (!strcmp(t, "tool_search_call")) {
                tc.name = xstrdup("tool_search");
            } else if (!strcmp(t, "local_shell_call")) {
                tc.name = xstrdup("local_shell");
            } else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "function_call_output") || !strcmp(t, "custom_tool_call_output")) {
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            msg.content = output ? output : xstrdup("");
            output = NULL;
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!strcmp(t, "reasoning")) {
            /* Stash so it merges into the next assistant message. summary is the
             * short-form list, content is the verbose chain. Either can be empty. */
            if (summary && summary[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, summary);
            }
            if (content && content[0]) {
                if (pending_reasoning.len) buf_putc(&pending_reasoning, '\n');
                buf_puts(&pending_reasoning, content);
            }
        } else if (!strcmp(t, "local_shell_call") || !strcmp(t, "web_search_call") ||
                   !strcmp(t, "tool_search_call") || !strcmp(t, "image_generation_call"))
        {
            /* Hosted-tool history isn't natively supported (DS4 doesn't register
             * these tools), but a Codex client may still replay them when the
             * model used them in a prior turn. Surface them as function_call
             * shaped history so the next prompt retains the action that ran. */
            tool_call tc = {0};
            tc.id = xstrdup(call_id ? call_id : item_id ? item_id : "");
            if (!strcmp(t, "tool_search_call")) {
                tc.name = xstrdup("tool_search");
            } else if (!strcmp(t, "local_shell_call")) {
                tc.name = xstrdup("local_shell");
            } else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
} else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "local_shell_call_output") ||
                   !strcmp(t, "web_search_call_output") ||
                   !strcmp(t, "tool_search_output") ||
                   !strcmp(t, "tool_search_call_output") ||
                   !strcmp(t, "image_generation_call_output"))
        {
            if (!strcmp(t, "tool_search_output") && tools_json &&
                loaded_tool_schemas && orders)
            {
                const char *tools_p = tools_json;
                char *schemas = NULL;
                if (!parse_tools_value(&tools_p, &schemas, orders)) {
                    free(schemas);
                    free(type);
                    free(role);
                    free(content);
                    free(name);
                    free(namespace);
                    free(call_id);
                    free(item_id);
                    free(arguments);
                    free(output);
                    free(input_str);
                    free(summary);
                    free(action);
                    free(result);
                    free(tools_json);
                    free(status_str);
                    buf_free(&pending_reasoning);
                    return false;
                }
                if (schemas && schemas[0]) {
                    if (loaded_tool_schemas->len) buf_putc(loaded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
} else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "local_shell_call_output") ||
                   !strcmp(t, "web_search_call_output") ||
                   !strcmp(t, "tool_search_output") ||
                   !strcmp(t, "tool_search_call_output") ||
                   !strcmp(t, "image_generation_call_output"))
        {
            if (!strcmp(t, "tool_search_output") && tools_json &&
                loaded_tool_schemas && orders)
            {
                const char *tools_p = tools_json;
                char *schemas = NULL;
                if (!parse_tools_value(&tools_p, &schemas, orders)) {
                    free(schemas);
                    free(type);
                    free(role);
                    free(content);
                    free(name);
                    free(namespace);
                    free(call_id);
                    free(item_id);
                    free(arguments);
                    free(output);
                    free(input_str);
                    free(summary);
                    free(action);
                    free(result);
                    free(tools_json);
                    free(status_str);
                    buf_free(&pending_reasoning);
                    return false;
                }
                if (schemas && schemas[0]) {
                    if (loaded_tool_schemas->len) buf_putc(loaded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
} else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "local_shell_call_output") ||
                   !strcmp(t, "web_search_call_output") ||
                   !strcmp(t, "tool_search_output") ||
                   !strcmp(t, "tool_search_call_output") ||
                   !strcmp(t, "image_generation_call_output"))
        {
            if (!strcmp(t, "tool_search_output") && tools_json &&
                loaded_tool_schemas && orders)
            {
                const char *tools_p = tools_json;
                char *schemas = NULL;
                if (!parse_tools_value(&tools_p, &schemas, orders)) {
                    free(schemas);
                    free(type);
                    free(role);
                    free(content);
                    free(name);
                    free(namespace);
                    free(call_id);
                    free(item_id);
                    free(arguments);
                    free(output);
                    free(input_str);
                    free(summary);
                    free(action);
                    free(result);
                    free(tools_json);
                    free(status_str);
                    buf_free(&pending_reasoning);
                    return false;
                }
                if (schemas && schemas[0]) {
                    if (loaded_tool_schemas->len) buf_putc(loaded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
} else {
                tc.name = xstrdup(t);
            }
            const char *args_src = action ? action :
                                   arguments ? arguments :
                                   input_str ? input_str : "{}";
            tc.arguments = xstrdup(args_src);
            chat_msg *last = msgs->len ? &msgs->v[msgs->len - 1] : NULL;
            if (last && !strcmp(last->role, "assistant")) {
                if (pending_reasoning.len && (!last->reasoning || !last->reasoning[0])) {
                    free(last->reasoning);
                    last->reasoning = buf_take(&pending_reasoning);
                }
                tool_calls_push(&last->calls, tc);
            } else {
                chat_msg msg = {0};
                msg.role = xstrdup("assistant");
                msg.content = xstrdup("");
                if (pending_reasoning.len) msg.reasoning = buf_take(&pending_reasoning);
                tool_calls_push(&msg.calls, tc);
                chat_msgs_push(msgs, msg);
            }
        } else if (!strcmp(t, "local_shell_call_output") ||
                   !strcmp(t, "web_search_call_output") ||
                   !strcmp(t, "tool_search_output") ||
                   !strcmp(t, "tool_search_call_output") ||
                   !strcmp(t, "image_generation_call_output"))
        {
            if (!strcmp(t, "tool_search_output") && tools_json &&
                loaded_tool_schemas && orders)
            {
                const char *tools_p = tools_json;
                char *schemas = NULL;
                if (!parse_tools_value(&tools_p, &schemas, orders)) {
                    free(schemas);
                    free(type);
                    free(role);
                    free(content);
                    free(name);
                    free(namespace);
                    free(call_id);
                    free(item_id);
                    free(arguments);
                    free(output);
                    free(input_str);
                    free(summary);
                    free(action);
                    free(result);
                    free(tools_json);
                    free(status_str);
                    buf_free(&pending_reasoning);
                    return false;
                }
                if (schemas && schemas[0]) {
                    if (loaded_tool_schemas->len) buf_putc(loaded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_server.c

```c
aded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            const char *body = output ? output :
                               result ? result :
                               tools_json ? tools_json : "";
            msg.content = xstrdup(body);
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!is_bookkeeping) {
            /* Anything we don't have an explicit branch for would silently
             * drop replay context. Fail the parse instead so the client sees
             * the limitation rather than ending up with stale generation
             * built on an incomplete history. Only compaction/context_compaction
             * (true Codex bookkeeping) are allowed to pass through silently. */
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            buf_free(&pending_reasoning);
            return false;
        }

        free(type);
        free(role);
        free(content);
        free(name);
        free(namespace);
        free(call_id);
        free(item_id);
        free(arguments);
        free(output);
        free(input_str);
        free(summary);
        free(action);
        free(result);
        free(tools_json);
        free(status_str);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    /* Trailing reasoning with no following message/tool item: attach it to an
     * empty assistant message so the next turn still renders a <think>...</think>
     * block. Dropping it loses model state when a previous response ended with
     * a reasoning-only incomplete turn and the client replays the history. */
    if (pending_reasoning.len) {
        chat_msg msg = {0};
        msg.role = xstrdup("assistant");
        msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_server.c

```c
aded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            const char *body = output ? output :
                               result ? result :
                               tools_json ? tools_json : "";
            msg.content = xstrdup(body);
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!is_bookkeeping) {
            /* Anything we don't have an explicit branch for would silently
             * drop replay context. Fail the parse instead so the client sees
             * the limitation rather than ending up with stale generation
             * built on an incomplete history. Only compaction/context_compaction
             * (true Codex bookkeeping) are allowed to pass through silently. */
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            buf_free(&pending_reasoning);
            return false;
        }

        free(type);
        free(role);
        free(content);
        free(name);
        free(namespace);
        free(call_id);
        free(item_id);
        free(arguments);
        free(output);
        free(input_str);
        free(summary);
        free(action);
        free(result);
        free(tools_json);
        free(status_str);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    /* Trailing reasoning with no following message/tool item: attach it to an
     * empty assistant message so the next turn still renders a <think>...</think>
     * block. Dropping it loses model state when a previous response ended with
     * a reasoning-only incomplete turn and the client replays the history. */
    if (pending_reasoning.len) {
        chat_msg msg = {0};
        msg.role = xstrdup("assistant");
        msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_server.c

```c
aded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            const char *body = output ? output :
                               result ? result :
                               tools_json ? tools_json : "";
            msg.content = xstrdup(body);
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!is_bookkeeping) {
            /* Anything we don't have an explicit branch for would silently
             * drop replay context. Fail the parse instead so the client sees
             * the limitation rather than ending up with stale generation
             * built on an incomplete history. Only compaction/context_compaction
             * (true Codex bookkeeping) are allowed to pass through silently. */
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            buf_free(&pending_reasoning);
            return false;
        }

        free(type);
        free(role);
        free(content);
        free(name);
        free(namespace);
        free(call_id);
        free(item_id);
        free(arguments);
        free(output);
        free(input_str);
        free(summary);
        free(action);
        free(result);
        free(tools_json);
        free(status_str);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    /* Trailing reasoning with no following message/tool item: attach it to an
     * empty assistant message so the next turn still renders a <think>...</think>
     * block. Dropping it loses model state when a previous response ended with
     * a reasoning-only incomplete turn and the client replays the history. */
    if (pending_reasoning.len) {
        chat_msg msg = {0};
        msg.role = xstrdup("assistant");
        msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_server.c

```c
aded_tool_schemas, '\n');
                    buf_puts(loaded_tool_schemas, schemas);
                }
                free(schemas);
            }
            chat_msg msg = {0};
            msg.role = xstrdup("tool");
            const char *body = output ? output :
                               result ? result :
                               tools_json ? tools_json : "";
            msg.content = xstrdup(body);
            if (call_id || item_id) {
                chat_msg_add_tool_call_id(&msg, call_id ? call_id : item_id);
            }
            chat_msgs_push(msgs, msg);
        } else if (!is_bookkeeping) {
            /* Anything we don't have an explicit branch for would silently
             * drop replay context. Fail the parse instead so the client sees
             * the limitation rather than ending up with stale generation
             * built on an incomplete history. Only compaction/context_compaction
             * (true Codex bookkeeping) are allowed to pass through silently. */
            free(type);
            free(role);
            free(content);
            free(name);
            free(namespace);
            free(call_id);
            free(item_id);
            free(arguments);
            free(output);
            free(input_str);
            free(summary);
            free(action);
            free(result);
            free(tools_json);
            free(status_str);
            buf_free(&pending_reasoning);
            return false;
        }

        free(type);
        free(role);
        free(content);
        free(name);
        free(namespace);
        free(call_id);
        free(item_id);
        free(arguments);
        free(output);
        free(input_str);
        free(summary);
        free(action);
        free(result);
        free(tools_json);
        free(status_str);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    /* Trailing reasoning with no following message/tool item: attach it to an
     * empty assistant message so the next turn still renders a <think>...</think>
     * block. Dropping it loses model state when a previous response ended with
     * a reasoning-only incomplete turn and the client replays the history. */
    if (pending_reasoning.len) {
        chat_msg msg = {0};
        msg.role = xstrdup("assistant");
        msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
    buf_free(&pending_reasoning);
    return false;
}

/* Responses API has `reasoning: {"effort": "...", "summary": "..."}`. effort
 * controls thinking depth; summary mode (auto/concise/detailed) controls
 * whether the wire emits summary deltas at all — per the spec, no reasoning
 * summary is surfaced unless the client opts in. */
static bool parse_responses_reasoning(const char **p, ds4_think_mode *effort,
                                      bool *summary_opted_in,
                                      bool *effort_seen) {
    json_ws(p);
    if (json_lit(p, "null")) return true;
    if (**p != '{') return json_skip_value(p);
    (*p)++;
    json_ws(p);
    while (**p && **p != '}') {
        char *key = NULL;
        if (!json_string(p, &key)) return false;
        json_ws(p);
        if (**p != ':') {
            free(key);
            return false;
        }
        (*p)++;
        if (!strcmp(key, "effort")) {
            json_ws(p);
            /* A `null` effort doesn't change thinking_enabled — it's the same
             * as omitting the field. Only treat the field as a control if it
             * carried an actual value. */
            if (json_lit(p, "null")) {
                /* nothing */
            } else {
                if (!parse_reasoning_effort_value(p, effort)) {
                    free(key);
                    return false;
                }
                if (effort_seen) *effort_seen = true;
            }
        } else if (!strcmp(key, "summary")) {
            json_ws(p);
            if (json_lit(p, "null")) {
                /* explicit null disables summary */
            } else if (**p == '"') {
                char *mode = NULL;
                if (!json_string(p, &mode)) {
                    free(key);
                    return false;
                }
                if (summary_opted_in &&
                    (!strcmp(mode, "auto") ||
                     !strcmp(mode, "concise") ||
                     !strcmp(mode, "detailed")))
                {
                    *summary_opted_in = true;
                }
                free(mode);
            } else if (!json_skip_value(p)) {
                free(key);
                return false;
            }
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
    buf_free(&pending_reasoning);
    return false;
}

/* Responses API has `reasoning: {"effort": "...", "summary": "..."}`. effort
 * controls thinking depth; summary mode (auto/concise/detailed) controls
 * whether the wire emits summary deltas at all — per the spec, no reasoning
 * summary is surfaced unless the client opts in. */
static bool parse_responses_reasoning(const char **p, ds4_think_mode *effort,
                                      bool *summary_opted_in,
                                      bool *effort_seen) {
    json_ws(p);
    if (json_lit(p, "null")) return true;
    if (**p != '{') return json_skip_value(p);
    (*p)++;
    json_ws(p);
    while (**p && **p != '}') {
        char *key = NULL;
        if (!json_string(p, &key)) return false;
        json_ws(p);
        if (**p != ':') {
            free(key);
            return false;
        }
        (*p)++;
        if (!strcmp(key, "effort")) {
            json_ws(p);
            /* A `null` effort doesn't change thinking_enabled — it's the same
             * as omitting the field. Only treat the field as a control if it
             * carried an actual value. */
            if (json_lit(p, "null")) {
                /* nothing */
            } else {
                if (!parse_reasoning_effort_value(p, effort)) {
                    free(key);
                    return false;
                }
                if (effort_seen) *effort_seen = true;
            }
        } else if (!strcmp(key, "summary")) {
            json_ws(p);
            if (json_lit(p, "null")) {
                /* explicit null disables summary */
            } else if (**p == '"') {
                char *mode = NULL;
                if (!json_string(p, &mode)) {
                    free(key);
                    return false;
                }
                if (summary_opted_in &&
                    (!strcmp(mode, "auto") ||
                     !strcmp(mode, "concise") ||
                     !strcmp(mode, "detailed")))
                {
                    *summary_opted_in = true;
                }
                free(mode);
            } else if (!json_skip_value(p)) {
                free(key);
                return false;
            }
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
    buf_free(&pending_reasoning);
    return false;
}

/* Responses API has `reasoning: {"effort": "...", "summary": "..."}`. effort
 * controls thinking depth; summary mode (auto/concise/detailed) controls
 * whether the wire emits summary deltas at all — per the spec, no reasoning
 * summary is surfaced unless the client opts in. */
static bool parse_responses_reasoning(const char **p, ds4_think_mode *effort,
                                      bool *summary_opted_in,
                                      bool *effort_seen) {
    json_ws(p);
    if (json_lit(p, "null")) return true;
    if (**p != '{') return json_skip_value(p);
    (*p)++;
    json_ws(p);
    while (**p && **p != '}') {
        char *key = NULL;
        if (!json_string(p, &key)) return false;
        json_ws(p);
        if (**p != ':') {
            free(key);
            return false;
        }
        (*p)++;
        if (!strcmp(key, "effort")) {
            json_ws(p);
            /* A `null` effort doesn't change thinking_enabled — it's the same
             * as omitting the field. Only treat the field as a control if it
             * carried an actual value. */
            if (json_lit(p, "null")) {
                /* nothing */
            } else {
                if (!parse_reasoning_effort_value(p, effort)) {
                    free(key);
                    return false;
                }
                if (effort_seen) *effort_seen = true;
            }
        } else if (!strcmp(key, "summary")) {
            json_ws(p);
            if (json_lit(p, "null")) {
                /* explicit null disables summary */
            } else if (**p == '"') {
                char *mode = NULL;
                if (!json_string(p, &mode)) {
                    free(key);
                    return false;
                }
                if (summary_opted_in &&
                    (!strcmp(mode, "auto") ||
                     !strcmp(mode, "concise") ||
                     !strcmp(mode, "detailed")))
                {
                    *summary_opted_in = true;
                }
                free(mode);
            } else if (!json_skip_value(p)) {
                free(key);
                return false;
            }
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
msg.content = xstrdup("");
        msg.reasoning = buf_take(&pending_reasoning);
        chat_msgs_push(msgs, msg);
    }
    buf_free(&pending_reasoning);
    return true;
fail:
    buf_free(&pending_reasoning);
    return false;
}

/* Responses API has `reasoning: {"effort": "...", "summary": "..."}`. effort
 * controls thinking depth; summary mode (auto/concise/detailed) controls
 * whether the wire emits summary deltas at all — per the spec, no reasoning
 * summary is surfaced unless the client opts in. */
static bool parse_responses_reasoning(const char **p, ds4_think_mode *effort,
                                      bool *summary_opted_in,
                                      bool *effort_seen) {
    json_ws(p);
    if (json_lit(p, "null")) return true;
    if (**p != '{') return json_skip_value(p);
    (*p)++;
    json_ws(p);
    while (**p && **p != '}') {
        char *key = NULL;
        if (!json_string(p, &key)) return false;
        json_ws(p);
        if (**p != ':') {
            free(key);
            return false;
        }
        (*p)++;
        if (!strcmp(key, "effort")) {
            json_ws(p);
            /* A `null` effort doesn't change thinking_enabled — it's the same
             * as omitting the field. Only treat the field as a control if it
             * carried an actual value. */
            if (json_lit(p, "null")) {
                /* nothing */
            } else {
                if (!parse_reasoning_effort_value(p, effort)) {
                    free(key);
                    return false;
                }
                if (effort_seen) *effort_seen = true;
            }
        } else if (!strcmp(key, "summary")) {
            json_ws(p);
            if (json_lit(p, "null")) {
                /* explicit null disables summary */
            } else if (**p == '"') {
                char *mode = NULL;
                if (!json_string(p, &mode)) {
                    free(key);
                    return false;
                }
                if (summary_opted_in &&
                    (!strcmp(mode, "auto") ||
                     !strcmp(mode, "concise") ||
                     !strcmp(mode, "detailed")))
                {
                    *summary_opted_in = true;
                }
                free(mode);
            } else if (!json_skip_value(p)) {
                free(key);
                return false;
            }
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    *out = buf_take(&b);
    return true;
fail:
    buf_free(&b);
    return false;
}

typedef enum {
    REQ_CHAT,
    REQ_COMPLETION,
} req_kind;

typedef enum {
    API_OPENAI,
    API_ANTHROPIC,
    API_RESPONSES,
} api_style;

static void random_tool_id(char *dst, size_t dstlen, api_style api) {
    static uint64_t fallback_ctr;
    unsigned char bytes[16];
    const char *prefix = api == API_ANTHROPIC ? "toolu_" : "call_";
    size_t pos = snprintf(dst, dstlen, "%s", prefix);
    if (pos >= dstlen) return;

    if (!random_bytes(bytes, sizeof(bytes))) {
        uint64_t a = ((uint64_t)time(NULL) << 32) ^ (uint64_t)getpid();
        uint64_t b = ++fallback_ctr ^ (uint64_t)(uintptr_t)dst;
        memcpy(bytes, &a, sizeof(a));
        memcpy(bytes + sizeof(a), &b, sizeof(b));
    }

    static const char hex[] = "0123456789abcdef";
    for (size_t i = 0; i < sizeof(bytes) && pos + 2 < dstlen; i++) {
        dst[pos++] = hex[bytes[i] >> 4];
        dst[pos++] = hex[bytes[i] & 15];
    }
    dst[pos] = '\0';
}

typedef struct server server;

typedef struct {
    char *id;
    char *name;
    char *arguments;
} tool_call;

typedef struct {
    tool_call *v;
    int len;
    int cap;
    char *raw_dsml;
} tool_calls;

typedef struct {
    int mem;
    int disk;
    int canonical;
    int missing_ids;
} tool_replay_stats;

typedef struct {
    char *name;
    char *wire_name;
    char *namespace;
    /* Distinguish the Responses hosted tool from a normal function that
     * happens to be named "tool_search". */
    bool responses_tool_search;
    char **prop;
    int len;
    int cap;
} tool_schema_order;

typedef struct {
    tool_schema_order *v;
    int len;
    int cap;
} tool_schema_orders;

typedef struct {
    char *role;
    char *content;
    char *reasoning;
    char *tool_call_id;
    char **tool_call_ids;
    int tool_call_ids_len;
    int tool_call_ids_cap;
    tool_calls calls;
} chat_msg;

typedef struct {
    chat_msg *v;
    int len;
    int cap;
} chat_msgs;

static void tool_memory_attach_to_messages(server *s, chat_msgs *msgs,
                                           tool_replay_stats *stats);
static bool tool_memory_has_id(server *s, const char *id);
static void kv_cache_restore_tool_memory_for_messages(server *s, const chat_msgs *msgs);

typedef struct {
    char **v;
    int len;
    int cap;
    size_t max_len;
} stop_list;

static void stop_list_clear(stop_list *stops);
static bool id_list_contains(const stop_list *ids, const char *id);
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    *out = buf_take(&b);
    return true;
fail:
    buf_free(&b);
    return false;
}

typedef enum {
    REQ_CHAT,
    REQ_COMPLETION,
} req_kind;

typedef enum {
    API_OPENAI,
    API_ANTHROPIC,
    API_RESPONSES,
} api_style;

static void random_tool_id(char *dst, size_t dstlen, api_style api) {
    static uint64_t fallback_ctr;
    unsigned char bytes[16];
    const char *prefix = api == API_ANTHROPIC ? "toolu_" : "call_";
    size_t pos = snprintf(dst, dstlen, "%s", prefix);
    if (pos >= dstlen) return;

    if (!random_bytes(bytes, sizeof(bytes))) {
        uint64_t a = ((uint64_t)time(NULL) << 32) ^ (uint64_t)getpid();
        uint64_t b = ++fallback_ctr ^ (uint64_t)(uintptr_t)dst;
        memcpy(bytes, &a, sizeof(a));
        memcpy(bytes + sizeof(a), &b, sizeof(b));
    }

    static const char hex[] = "0123456789abcdef";
    for (size_t i = 0; i < sizeof(bytes) && pos + 2 < dstlen; i++) {
        dst[pos++] = hex[bytes[i] >> 4];
        dst[pos++] = hex[bytes[i] & 15];
    }
    dst[pos] = '\0';
}

typedef struct server server;

typedef struct {
    char *id;
    char *name;
    char *arguments;
} tool_call;

typedef struct {
    tool_call *v;
    int len;
    int cap;
    char *raw_dsml;
} tool_calls;

typedef struct {
    int mem;
    int disk;
    int canonical;
    int missing_ids;
} tool_replay_stats;

typedef struct {
    char *name;
    char *wire_name;
    char *namespace;
    /* Distinguish the Responses hosted tool from a normal function that
     * happens to be named "tool_search". */
    bool responses_tool_search;
    char **prop;
    int len;
    int cap;
} tool_schema_order;

typedef struct {
    tool_schema_order *v;
    int len;
    int cap;
} tool_schema_orders;

typedef struct {
    char *role;
    char *content;
    char *reasoning;
    char *tool_call_id;
    char **tool_call_ids;
    int tool_call_ids_len;
    int tool_call_ids_cap;
    tool_calls calls;
} chat_msg;

typedef struct {
    chat_msg *v;
    int len;
    int cap;
} chat_msgs;

static void tool_memory_attach_to_messages(server *s, chat_msgs *msgs,
                                           tool_replay_stats *stats);
static bool tool_memory_has_id(server *s, const char *id);
static void kv_cache_restore_tool_memory_for_messages(server *s, const chat_msgs *msgs);

typedef struct {
    char **v;
    int len;
    int cap;
    size_t max_len;
} stop_list;

static void stop_list_clear(stop_list *stops);
static bool id_list_contains(const stop_list *ids, const char *id);
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    *out = buf_take(&b);
    return true;
fail:
    buf_free(&b);
    return false;
}

typedef enum {
    REQ_CHAT,
    REQ_COMPLETION,
} req_kind;

typedef enum {
    API_OPENAI,
    API_ANTHROPIC,
    API_RESPONSES,
} api_style;

static void random_tool_id(char *dst, size_t dstlen, api_style api) {
    static uint64_t fallback_ctr;
    unsigned char bytes[16];
    const char *prefix = api == API_ANTHROPIC ? "toolu_" : "call_";
    size_t pos = snprintf(dst, dstlen, "%s", prefix);
    if (pos >= dstlen) return;

    if (!random_bytes(bytes, sizeof(bytes))) {
        uint64_t a = ((uint64_t)time(NULL) << 32) ^ (uint64_t)getpid();
        uint64_t b = ++fallback_ctr ^ (uint64_t)(uintptr_t)dst;
        memcpy(bytes, &a, sizeof(a));
        memcpy(bytes + sizeof(a), &b, sizeof(b));
    }

    static const char hex[] = "0123456789abcdef";
    for (size_t i = 0; i < sizeof(bytes) && pos + 2 < dstlen; i++) {
        dst[pos++] = hex[bytes[i] >> 4];
        dst[pos++] = hex[bytes[i] & 15];
    }
    dst[pos] = '\0';
}

typedef struct server server;

typedef struct {
    char *id;
    char *name;
    char *arguments;
} tool_call;

typedef struct {
    tool_call *v;
    int len;
    int cap;
    char *raw_dsml;
} tool_calls;

typedef struct {
    int mem;
    int disk;
    int canonical;
    int missing_ids;
} tool_replay_stats;

typedef struct {
    char *name;
    char *wire_name;
    char *namespace;
    /* Distinguish the Responses hosted tool from a normal function that
     * happens to be named "tool_search". */
    bool responses_tool_search;
    char **prop;
    int len;
    int cap;
} tool_schema_order;

typedef struct {
    tool_schema_order *v;
    int len;
    int cap;
} tool_schema_orders;

typedef struct {
    char *role;
    char *content;
    char *reasoning;
    char *tool_call_id;
    char **tool_call_ids;
    int tool_call_ids_len;
    int tool_call_ids_cap;
    tool_calls calls;
} chat_msg;

typedef struct {
    chat_msg *v;
    int len;
    int cap;
} chat_msgs;

static void tool_memory_attach_to_messages(server *s, chat_msgs *msgs,
                                           tool_replay_stats *stats);
static bool tool_memory_has_id(server *s, const char *id);
static void kv_cache_restore_tool_memory_for_messages(server *s, const chat_msgs *msgs);

typedef struct {
    char **v;
    int len;
    int cap;
    size_t max_len;
} stop_list;

static void stop_list_clear(stop_list *stops);
static bool id_list_contains(const stop_list *ids, const char *id);
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_server.c

```c
json_ws(p);
    }
    if (**p != ']') goto fail;
    (*p)++;
    *out = buf_take(&b);
    return true;
fail:
    buf_free(&b);
    return false;
}

typedef enum {
    REQ_CHAT,
    REQ_COMPLETION,
} req_kind;

typedef enum {
    API_OPENAI,
    API_ANTHROPIC,
    API_RESPONSES,
} api_style;

static void random_tool_id(char *dst, size_t dstlen, api_style api) {
    static uint64_t fallback_ctr;
    unsigned char bytes[16];
    const char *prefix = api == API_ANTHROPIC ? "toolu_" : "call_";
    size_t pos = snprintf(dst, dstlen, "%s", prefix);
    if (pos >= dstlen) return;

    if (!random_bytes(bytes, sizeof(bytes))) {
        uint64_t a = ((uint64_t)time(NULL) << 32) ^ (uint64_t)getpid();
        uint64_t b = ++fallback_ctr ^ (uint64_t)(uintptr_t)dst;
        memcpy(bytes, &a, sizeof(a));
        memcpy(bytes + sizeof(a), &b, sizeof(b));
    }

    static const char hex[] = "0123456789abcdef";
    for (size_t i = 0; i < sizeof(bytes) && pos + 2 < dstlen; i++) {
        dst[pos++] = hex[bytes[i] >> 4];
        dst[pos++] = hex[bytes[i] & 15];
    }
    dst[pos] = '\0';
}

typedef struct server server;

typedef struct {
    char *id;
    char *name;
    char *arguments;
} tool_call;

typedef struct {
    tool_call *v;
    int len;
    int cap;
    char *raw_dsml;
} tool_calls;

typedef struct {
    int mem;
    int disk;
    int canonical;
    int missing_ids;
} tool_replay_stats;

typedef struct {
    char *name;
    char *wire_name;
    char *namespace;
    /* Distinguish the Responses hosted tool from a normal function that
     * happens to be named "tool_search". */
    bool responses_tool_search;
    char **prop;
    int len;
    int cap;
} tool_schema_order;

typedef struct {
    tool_schema_order *v;
    int len;
    int cap;
} tool_schema_orders;

typedef struct {
    char *role;
    char *content;
    char *reasoning;
    char *tool_call_id;
    char **tool_call_ids;
    int tool_call_ids_len;
    int tool_call_ids_cap;
    tool_calls calls;
} chat_msg;

typedef struct {
    chat_msg *v;
    int len;
    int cap;
} chat_msgs;

static void tool_memory_attach_to_messages(server *s, chat_msgs *msgs,
                                           tool_replay_stats *stats);
static bool tool_memory_has_id(server *s, const char *id);
static void kv_cache_restore_tool_memory_for_messages(server *s, const chat_msgs *msgs);

typedef struct {
    char **v;
    int len;
    int cap;
    size_t max_len;
} stop_list;

static void stop_list_clear(stop_list *stops);
static bool id_list_contains(const stop_list *ids, const char *id);
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
}
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != '}') return false;
    (*p)++;
    return true;
}

static bool parse_responses_request(ds4_engine *e, server *s, const char *body, int def_tokens,
                                    int ctx_size, request *r, char *err, size_t errlen) {
    request_init(r, REQ_CHAT, def_tokens);
    r->api = API_RESPONSES;
    const char *p = body;
    bool got_input = false;
    bool tool_choice_none = false;
    bool got_thinking = false;
    bool thinking_enabled = true;
    ds4_think_mode reasoning_effort = DS4_THINK_HIGH;
    chat_msgs msgs = {0};
    buf loaded_tool_schemas = {0};
    char *instructions = NULL;
    char *tool_schemas = NULL;

    json_ws(&p);
    if (*p != '{') goto bad;
    p++;
    json_ws(&p);
    while (*p && *p != '}') {
        char *key = NULL;
        if (!json_string(&p, &key)) goto bad;
        json_ws(&p);
        if (*p != ':') {
            free(key);
            goto bad;
        }
        p++;
        if (!strcmp(key, "input")) {
            chat_msgs_free(&msgs);
            json_ws(&p);
            /* Codex CLI always sends `input` as an array; tolerate bare strings
             * for parity with other Responses-API callers. */
            if (*p == '"') {
                char *plain = NULL;
                if (!json_string(&p, &plain)) {
                    free(key);
                    goto bad;
                }
                chat_msg msg = {0};
                msg.role = xstrdup("user");
                msg.content = plain;
                chat_msgs_push(&msgs, msg);
            } else if (!parse_responses_input(&p, &msgs, &loaded_tool_schemas,
                                              &r->tool_orders)) {
                free(key);
                goto bad;
            }
            got_input = true;
        } else if (!strcmp(key, "instructions")) {
            free(instructions);
            instructions = NULL;
            json_ws(&p);
            if (json_lit(&p, "null")) {
                instructions = xstrdup("");
            } else if (!json_string(&p, &instructions)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tools")) {
            free(tool_schemas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
}
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != '}') return false;
    (*p)++;
    return true;
}

static bool parse_responses_request(ds4_engine *e, server *s, const char *body, int def_tokens,
                                    int ctx_size, request *r, char *err, size_t errlen) {
    request_init(r, REQ_CHAT, def_tokens);
    r->api = API_RESPONSES;
    const char *p = body;
    bool got_input = false;
    bool tool_choice_none = false;
    bool got_thinking = false;
    bool thinking_enabled = true;
    ds4_think_mode reasoning_effort = DS4_THINK_HIGH;
    chat_msgs msgs = {0};
    buf loaded_tool_schemas = {0};
    char *instructions = NULL;
    char *tool_schemas = NULL;

    json_ws(&p);
    if (*p != '{') goto bad;
    p++;
    json_ws(&p);
    while (*p && *p != '}') {
        char *key = NULL;
        if (!json_string(&p, &key)) goto bad;
        json_ws(&p);
        if (*p != ':') {
            free(key);
            goto bad;
        }
        p++;
        if (!strcmp(key, "input")) {
            chat_msgs_free(&msgs);
            json_ws(&p);
            /* Codex CLI always sends `input` as an array; tolerate bare strings
             * for parity with other Responses-API callers. */
            if (*p == '"') {
                char *plain = NULL;
                if (!json_string(&p, &plain)) {
                    free(key);
                    goto bad;
                }
                chat_msg msg = {0};
                msg.role = xstrdup("user");
                msg.content = plain;
                chat_msgs_push(&msgs, msg);
            } else if (!parse_responses_input(&p, &msgs, &loaded_tool_schemas,
                                              &r->tool_orders)) {
                free(key);
                goto bad;
            }
            got_input = true;
        } else if (!strcmp(key, "instructions")) {
            free(instructions);
            instructions = NULL;
            json_ws(&p);
            if (json_lit(&p, "null")) {
                instructions = xstrdup("");
            } else if (!json_string(&p, &instructions)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tools")) {
            free(tool_schemas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
}
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != '}') return false;
    (*p)++;
    return true;
}

static bool parse_responses_request(ds4_engine *e, server *s, const char *body, int def_tokens,
                                    int ctx_size, request *r, char *err, size_t errlen) {
    request_init(r, REQ_CHAT, def_tokens);
    r->api = API_RESPONSES;
    const char *p = body;
    bool got_input = false;
    bool tool_choice_none = false;
    bool got_thinking = false;
    bool thinking_enabled = true;
    ds4_think_mode reasoning_effort = DS4_THINK_HIGH;
    chat_msgs msgs = {0};
    buf loaded_tool_schemas = {0};
    char *instructions = NULL;
    char *tool_schemas = NULL;

    json_ws(&p);
    if (*p != '{') goto bad;
    p++;
    json_ws(&p);
    while (*p && *p != '}') {
        char *key = NULL;
        if (!json_string(&p, &key)) goto bad;
        json_ws(&p);
        if (*p != ':') {
            free(key);
            goto bad;
        }
        p++;
        if (!strcmp(key, "input")) {
            chat_msgs_free(&msgs);
            json_ws(&p);
            /* Codex CLI always sends `input` as an array; tolerate bare strings
             * for parity with other Responses-API callers. */
            if (*p == '"') {
                char *plain = NULL;
                if (!json_string(&p, &plain)) {
                    free(key);
                    goto bad;
                }
                chat_msg msg = {0};
                msg.role = xstrdup("user");
                msg.content = plain;
                chat_msgs_push(&msgs, msg);
            } else if (!parse_responses_input(&p, &msgs, &loaded_tool_schemas,
                                              &r->tool_orders)) {
                free(key);
                goto bad;
            }
            got_input = true;
        } else if (!strcmp(key, "instructions")) {
            free(instructions);
            instructions = NULL;
            json_ws(&p);
            if (json_lit(&p, "null")) {
                instructions = xstrdup("");
            } else if (!json_string(&p, &instructions)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tools")) {
            free(tool_schemas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_server.c

```c
}
        } else if (!json_skip_value(p)) {
            free(key);
            return false;
        }
        free(key);
        json_ws(p);
        if (**p == ',') (*p)++;
        json_ws(p);
    }
    if (**p != '}') return false;
    (*p)++;
    return true;
}

static bool parse_responses_request(ds4_engine *e, server *s, const char *body, int def_tokens,
                                    int ctx_size, request *r, char *err, size_t errlen) {
    request_init(r, REQ_CHAT, def_tokens);
    r->api = API_RESPONSES;
    const char *p = body;
    bool got_input = false;
    bool tool_choice_none = false;
    bool got_thinking = false;
    bool thinking_enabled = true;
    ds4_think_mode reasoning_effort = DS4_THINK_HIGH;
    chat_msgs msgs = {0};
    buf loaded_tool_schemas = {0};
    char *instructions = NULL;
    char *tool_schemas = NULL;

    json_ws(&p);
    if (*p != '{') goto bad;
    p++;
    json_ws(&p);
    while (*p && *p != '}') {
        char *key = NULL;
        if (!json_string(&p, &key)) goto bad;
        json_ws(&p);
        if (*p != ':') {
            free(key);
            goto bad;
        }
        p++;
        if (!strcmp(key, "input")) {
            chat_msgs_free(&msgs);
            json_ws(&p);
            /* Codex CLI always sends `input` as an array; tolerate bare strings
             * for parity with other Responses-API callers. */
            if (*p == '"') {
                char *plain = NULL;
                if (!json_string(&p, &plain)) {
                    free(key);
                    goto bad;
                }
                chat_msg msg = {0};
                msg.role = xstrdup("user");
                msg.content = plain;
                chat_msgs_push(&msgs, msg);
            } else if (!parse_responses_input(&p, &msgs, &loaded_tool_schemas,
                                              &r->tool_orders)) {
                free(key);
                goto bad;
            }
            got_input = true;
        } else if (!strcmp(key, "instructions")) {
            free(instructions);
            instructions = NULL;
            json_ws(&p);
            if (json_lit(&p, "null")) {
                instructions = xstrdup("");
            } else if (!json_string(&p, &instructions)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tools")) {
            free(tool_schemas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
emas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tool_choice")) {
            json_ws(&p);
            if (*p == '"') {
                char *choice = NULL;
                if (!json_string(&p, &choice)) {
                    free(key);
                    goto bad;
                }
                /* DS4 honours "none" (disable tools) and "auto" (model decides).
                 * "required" and explicit function targets need constrained
                 * decoding we don't implement — reject so clients see the
                 * limitation instead of silently downgrading to auto. */
                if (!strcmp(choice, "none")) {
                    tool_choice_none = true;
                } else if (strcmp(choice, "auto") != 0) {
                    snprintf(err, errlen, "tool_choice=%s not supported", choice);
                    free(choice);
                    free(key);
                    chat_msgs_free(&msgs);
                    buf_free(&loaded_tool_schemas);
                    free(instructions);
                    free(tool_schemas);
                    request_free(r);
                    return false;
                }
                free(choice);
            } else if (*p == '{') {
                snprintf(err, errlen, "forced tool_choice not supported");
                free(key);
                chat_msgs_free(&msgs);
                buf_free(&loaded_tool_schemas);
                free(instructions);
                free(tool_schemas);
                request_free(r);
                return false;
            } else if (!json_skip_value(&p)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "model")) {
            free(r->model);
            if (!json_string(&p, &r->model)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "max_output_tokens") || !strcmp(key, "max_tokens")) {
            if (!json_int(&p, &r->max_tokens)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "temperature")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
                goto bad;
            }
            r->temperature = (float)v;
        } else if (!strcmp(key, "top_p")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
emas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tool_choice")) {
            json_ws(&p);
            if (*p == '"') {
                char *choice = NULL;
                if (!json_string(&p, &choice)) {
                    free(key);
                    goto bad;
                }
                /* DS4 honours "none" (disable tools) and "auto" (model decides).
                 * "required" and explicit function targets need constrained
                 * decoding we don't implement — reject so clients see the
                 * limitation instead of silently downgrading to auto. */
                if (!strcmp(choice, "none")) {
                    tool_choice_none = true;
                } else if (strcmp(choice, "auto") != 0) {
                    snprintf(err, errlen, "tool_choice=%s not supported", choice);
                    free(choice);
                    free(key);
                    chat_msgs_free(&msgs);
                    buf_free(&loaded_tool_schemas);
                    free(instructions);
                    free(tool_schemas);
                    request_free(r);
                    return false;
                }
                free(choice);
            } else if (*p == '{') {
                snprintf(err, errlen, "forced tool_choice not supported");
                free(key);
                chat_msgs_free(&msgs);
                buf_free(&loaded_tool_schemas);
                free(instructions);
                free(tool_schemas);
                request_free(r);
                return false;
            } else if (!json_skip_value(&p)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "model")) {
            free(r->model);
            if (!json_string(&p, &r->model)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "max_output_tokens") || !strcmp(key, "max_tokens")) {
            if (!json_int(&p, &r->max_tokens)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "temperature")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
                goto bad;
            }
            r->temperature = (float)v;
        } else if (!strcmp(key, "top_p")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
emas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tool_choice")) {
            json_ws(&p);
            if (*p == '"') {
                char *choice = NULL;
                if (!json_string(&p, &choice)) {
                    free(key);
                    goto bad;
                }
                /* DS4 honours "none" (disable tools) and "auto" (model decides).
                 * "required" and explicit function targets need constrained
                 * decoding we don't implement — reject so clients see the
                 * limitation instead of silently downgrading to auto. */
                if (!strcmp(choice, "none")) {
                    tool_choice_none = true;
                } else if (strcmp(choice, "auto") != 0) {
                    snprintf(err, errlen, "tool_choice=%s not supported", choice);
                    free(choice);
                    free(key);
                    chat_msgs_free(&msgs);
                    buf_free(&loaded_tool_schemas);
                    free(instructions);
                    free(tool_schemas);
                    request_free(r);
                    return false;
                }
                free(choice);
            } else if (*p == '{') {
                snprintf(err, errlen, "forced tool_choice not supported");
                free(key);
                chat_msgs_free(&msgs);
                buf_free(&loaded_tool_schemas);
                free(instructions);
                free(tool_schemas);
                request_free(r);
                return false;
            } else if (!json_skip_value(&p)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "model")) {
            free(r->model);
            if (!json_string(&p, &r->model)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "max_output_tokens") || !strcmp(key, "max_tokens")) {
            if (!json_int(&p, &r->max_tokens)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "temperature")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
                goto bad;
            }
            r->temperature = (float)v;
        } else if (!strcmp(key, "top_p")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_server.c

```c
emas);
            tool_schemas = NULL;
            if (!parse_tools_value(&p, &tool_schemas, &r->tool_orders)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "tool_choice")) {
            json_ws(&p);
            if (*p == '"') {
                char *choice = NULL;
                if (!json_string(&p, &choice)) {
                    free(key);
                    goto bad;
                }
                /* DS4 honours "none" (disable tools) and "auto" (model decides).
                 * "required" and explicit function targets need constrained
                 * decoding we don't implement — reject so clients see the
                 * limitation instead of silently downgrading to auto. */
                if (!strcmp(choice, "none")) {
                    tool_choice_none = true;
                } else if (strcmp(choice, "auto") != 0) {
                    snprintf(err, errlen, "tool_choice=%s not supported", choice);
                    free(choice);
                    free(key);
                    chat_msgs_free(&msgs);
                    buf_free(&loaded_tool_schemas);
                    free(instructions);
                    free(tool_schemas);
                    request_free(r);
                    return false;
                }
                free(choice);
            } else if (*p == '{') {
                snprintf(err, errlen, "forced tool_choice not supported");
                free(key);
                chat_msgs_free(&msgs);
                buf_free(&loaded_tool_schemas);
                free(instructions);
                free(tool_schemas);
                request_free(r);
                return false;
            } else if (!json_skip_value(&p)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "model")) {
            free(r->model);
            if (!json_string(&p, &r->model)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "max_output_tokens") || !strcmp(key, "max_tokens")) {
            if (!json_int(&p, &r->max_tokens)) {
                free(key);
                goto bad;
            }
        } else if (!strcmp(key, "temperature")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
                goto bad;
            }
            r->temperature = (float)v;
        } else if (!strcmp(key, "top_p")) {
            double v = 0.0;
            if (!json_number(&p, &v)) {
                free(key);
```<｜Assistant｜><think>