feat: add central llm runtime logging

src/lib/llm/client.ts

@@ -6,6 +6,7 @@ export interface GenerateInput {
   prompt: string;
   model?: string;
   temperature?: number;
+  task?: string;
 }
 
 export interface GenerateValidatedJsonInput<T> extends GenerateInput {
@@ -51,6 +52,51 @@ export function isLlmConfigured() {
   return getLlmProviderStatus().configured;
 }
 
+interface ChatCompletionResult {
+  choices: Array<{ message: { content?: string | null } }>;
+}
+
+type ChatCompletionRequest = {
+  model: string;
+  temperature: number;
+  response_format?: { type: "json_object" };
+  messages: Array<{ role: "system" | "user"; content: string }>;
+};
+
+let chatCompletionForTesting:
+  | ((request: ChatCompletionRequest) => Promise<ChatCompletionResult>)
+  | null = null;
+
+export function setChatCompletionForTesting(
+  handler: ((request: ChatCompletionRequest) => Promise<ChatCompletionResult>) | null,
+) {
+  chatCompletionForTesting = handler;
+}
+
+function getTask(input: GenerateInput) {
+  return input.task?.trim() || "unknown";
+}
+
+function truncateRaw(value: string, maxLength = 4000) {
+  return value.length > maxLength
+    ? `${value.slice(0, maxLength)}...[truncated ${value.length - maxLength} chars]`
+    : value;
+}
+
+function summarizeZodError(error: z.ZodError) {
+  return error.issues
+    .slice(0, 5)
+    .map((issue) => {
+      const path = issue.path.length > 0 ? issue.path.join(".") : "<root>";
+      return `${path}: ${issue.message}`;
+    })
+    .join("; ");
+}
+
+function quoteLogValue(value: string) {
+  return JSON.stringify(value);
+}
+
 function createClient() {
   const status = getLlmProviderStatus();
 
@@ -93,21 +139,40 @@ export async function generateText(input: GenerateInput) {
 }
 
 export async function generateJson<T>(input: GenerateInput): Promise<T> {
+  const task = getTask(input);
+  const startedAt = Date.now();
   try {
-    const { client, model } = createClient();
-    const response = await client.chat.completions.create({
-      model: input.model ?? model,
+    const status = getLlmProviderStatus();
+    if (!status.configured) {
+      throw new Error(status.reason ?? "LLM provider is not configured");
+    }
+    const effectiveModel = input.model ?? status.model;
+    console.info(
+      `[llm:start] provider=${status.provider} model=${effectiveModel} task=${task}`,
+    );
+    const request = {
+      model: effectiveModel,
       temperature: input.temperature ?? 0.1,
       response_format: { type: "json_object" },
       messages: [
         ...(input.system ? [{ role: "system" as const, content: input.system }] : []),
         { role: "user" as const, content: input.prompt },
       ],
-    });
+    } satisfies ChatCompletionRequest;
+    const response = chatCompletionForTesting
+      ? await chatCompletionForTesting(request)
+      : await createClient().client.chat.completions.create(request);
     const content = response.choices[0]?.message.content ?? "{}";
+    console.info(
+      `[llm:response] task=${task} duration_ms=${Date.now() - startedAt} raw=${truncateRaw(content)}`,
+    );
     return JSON.parse(content) as T;
   } catch (error) {
-    throw normalizeLlmError(error);
+    const normalized = normalizeLlmError(error);
+    console.error(
+      `[llm:error] task=${task} duration_ms=${Date.now() - startedAt} message=${quoteLogValue(normalized.message)}`,
+    );
+    throw normalized;
   }
 }
 
@@ -124,14 +189,25 @@ export async function generateValidatedJson<T>({
   schema,
   ...input
 }: GenerateValidatedJsonInput<T>): Promise<T | null> {
+  const task = getTask(input);
   if (!isLlmConfigured()) {
+    console.info(`[llm:validated] task=${task} ok=false reason=not_configured`);
     return null;
   }
 
   try {
     const generated = await generateJsonForValidation<unknown>(input);
-    return schema.parse(generated);
+    const parsed = schema.safeParse(generated);
+    if (parsed.success) {
+      console.info(`[llm:validated] task=${task} ok=true`);
+      return parsed.data;
+    }
+    console.warn(
+      `[llm:validated] task=${task} ok=false zod_error=${quoteLogValue(summarizeZodError(parsed.error))}`,
+    );
+    return null;
   } catch {
+    console.info(`[llm:validated] task=${task} ok=false reason=provider_error`);
     return null;
   }
 }