fix(agents): restore model-fetch info logs (#89648)

* fix(agents): restore model-fetch info logs

* docs(logging): document [model-fetch] default info-level visibility

[model-fetch] response metadata is always emitted at info level
regardless of OPENCLAW_DEBUG_MODEL_TRANSPORT, so users see basic
model transport hygiene (provider, API, model, status, latency)
without needing debug flags.

* docs(logging): clarify model-fetch start metadata visibility

docs/logging.md

@@ -210,6 +210,12 @@ These flags log through normal OpenClaw logging, so `openclaw logs --follow`
 and the Control UI Logs tab show them. Without the flags, the same diagnostics
 remain available at `debug` level.
 
+`[model-fetch]` start and response metadata (provider, API, model, status,
+latency, and request fields such as method, URL, timeout, proxy, and policy)
+is always emitted at `info` level regardless of
+`OPENCLAW_DEBUG_MODEL_TRANSPORT`, so basic model transport hygiene is visible
+without debug flags.
+
 ### Trace correlation
 
 File logs are JSONL. When a log call carries a valid diagnostic trace context,

src/agents/model-transport-debug.test.ts

@@ -0,0 +1,34 @@
+import { describe, expect, it, vi } from "vitest";
+import { emitModelTransportDebug } from "./model-transport-debug.js";
+
+describe("emitModelTransportDebug", () => {
+  function createLogger() {
+    return {
+      info: vi.fn(),
+      debug: vi.fn(),
+    } as unknown as Parameters<typeof emitModelTransportDebug>[0];
+  }
+
+  it("emits model-fetch metadata at info level by default", () => {
+    const log = createLogger();
+
+    emitModelTransportDebug(
+      log,
+      "[model-fetch] response provider=openai api=chat model=gpt status=200 latencyMs=42",
+    );
+
+    expect(log.info).toHaveBeenCalledWith(
+      "[model-fetch] response provider=openai api=chat model=gpt status=200 latencyMs=42",
+    );
+    expect(log.debug).not.toHaveBeenCalled();
+  });
+
+  it("keeps non-model-fetch transport diagnostics at debug level by default", () => {
+    const log = createLogger();
+
+    emitModelTransportDebug(log, "[model-sse] event type=response.output_text.delta");
+
+    expect(log.debug).toHaveBeenCalledWith("[model-sse] event type=response.output_text.delta");
+    expect(log.info).not.toHaveBeenCalled();
+  });
+});

src/agents/model-transport-debug.ts

@@ -68,9 +68,13 @@ function isModelTransportDebugEnabled(env: ModelTransportDebugEnv = process.env)
   );
 }
 
-/** Emits transport diagnostics at info level only when debug env explicitly enables them. */
+function isModelFetchMetadataMessage(message: string): boolean {
+  return message.startsWith("[model-fetch]");
+}
+
+/** Emits model-fetch metadata at info level by default; other diagnostics require debug env. */
 export function emitModelTransportDebug(log: SubsystemLogger, message: string): void {
-  if (isModelTransportDebugEnabled()) {
+  if (isModelFetchMetadataMessage(message) || isModelTransportDebugEnabled()) {
     log.info(message);
     return;
   }