diff --git a/js/dev/authorize.ts b/js/dev/authorize.ts
index 4f7592d17..eb91a2aaf 100644
--- a/js/dev/authorize.ts
+++ b/js/dev/authorize.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../src/debug-logger";
 import { Request, Response, NextFunction } from "express";
 import { IncomingHttpHeaders } from "http";
 import createError from "http-errors";
@@ -90,7 +91,7 @@ export function makeCheckAuthorized(allowedOrgName: string | undefined) {
       req.ctx.state = state;
       next();
     } catch (e) {
-      console.error("Authorization error:", e);
+      debugLogger.notice.error("Authorization error:", e);
       return next(createError(401, "Unauthorized"));
     }
   };
diff --git a/js/dev/errorHandler.ts b/js/dev/errorHandler.ts
index 12cd15e24..04f8d8fc6 100644
--- a/js/dev/errorHandler.ts
+++ b/js/dev/errorHandler.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../src/debug-logger";
 import { z } from "zod/v3";
 import { Request, Response, ErrorRequestHandler, NextFunction } from "express";
 import { HttpError } from "http-errors";
@@ -27,7 +28,7 @@ export const errorHandler: ErrorRequestHandler = (
     return;
   }
 
-  console.error("Internal server error", err);
+  debugLogger.notice.error("Internal server error", err);
   res.status(500).json({
     error: {
       message: "Internal server error",
diff --git a/js/dev/server.ts b/js/dev/server.ts
index 3118e8252..1ae70a61c 100644
--- a/js/dev/server.ts
+++ b/js/dev/server.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../src/debug-logger";
 import express, { NextFunction, Request, Response } from "express";
 import cors from "cors";
 import {
@@ -165,7 +166,7 @@ export function runDevServer(
         try {
           await validateParameters(parameters ?? {}, evaluator.parameters);
         } catch (e) {
-          console.error("Error validating parameters", e);
+          debugLogger.notice.error("Error validating parameters", e);
           if (
             e instanceof z.ZodError ||
             e instanceof ValidationError ||
@@ -280,7 +281,7 @@ export function runDevServer(
           res.json(summary.summary);
         }
       } catch (e) {
-        console.error("Error running eval", e);
+        debugLogger.notice.error("Error running eval", e);
         if (stream) {
           res.write(
             serializeSSEEvent({
diff --git a/js/src/auto-instrumentations/bundler/plugin.ts b/js/src/auto-instrumentations/bundler/plugin.ts
index 2c6d9a6d8..ff61dac11 100644
--- a/js/src/auto-instrumentations/bundler/plugin.ts
+++ b/js/src/auto-instrumentations/bundler/plugin.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../debug-logger";
 import { createUnplugin } from "unplugin";
 import { InstrumentationMatcher } from "../orchestrion-js";
 import { isAbsolute } from "node:path";
@@ -74,7 +75,9 @@ export const unplugin = createUnplugin<BundlerPluginOptions>((options = {}) => {
         return transformBundledModule(code, filePath, matcher, browser);
       } catch (error) {
         // If transformation fails, warn and return original code
-        console.warn(`Code transformation failed for ${id}: ${error}`);
+        debugLogger.notice.warn(
+          `Code transformation failed for ${id}: ${error}`,
+        );
         return null;
       }
     },
diff --git a/js/src/auto-instrumentations/bundler/webpack-loader.ts b/js/src/auto-instrumentations/bundler/webpack-loader.ts
index 6cb397208..67e1c3484 100644
--- a/js/src/auto-instrumentations/bundler/webpack-loader.ts
+++ b/js/src/auto-instrumentations/bundler/webpack-loader.ts
@@ -21,6 +21,8 @@
  * ```
  */
 
+import { debugLogger } from "../../debug-logger";
+
 import { InstrumentationMatcher } from "../orchestrion-js";
 import { getDefaultAutoInstrumentationConfigs } from "../configs/all";
 import { type BundlerPluginOptions } from "./plugin";
@@ -81,7 +83,7 @@ function codeTransformerLoader(
       callback(null, code, inputSourceMap);
     }
   } catch (error) {
-    console.warn(
+    debugLogger.notice.warn(
       `[code-transformer-loader] Error transforming ${resourcePath}:`,
       error,
     );
diff --git a/js/src/auto-instrumentations/hook.mts b/js/src/auto-instrumentations/hook.mts
index 8ea9de355..fb17fb214 100644
--- a/js/src/auto-instrumentations/hook.mts
+++ b/js/src/auto-instrumentations/hook.mts
@@ -13,6 +13,8 @@
  * - CJS modules: Transformed via patching Module._compile
  */
 
+import { debugLogger } from "../debug-logger.js";
+
 import { register } from "node:module";
 import {
   isInstrumentationIntegrationDisabled,
@@ -57,20 +59,16 @@ if (!alreadyApplied) {
   try {
     patchCommonJS(allConfigs);
 
-    if (process.env.DEBUG === "@braintrust*" || process.env.DEBUG === "*") {
-      console.log(
-        "[Braintrust] Auto-instrumentation active (ESM + CJS) for:",
-        allConfigs.map((c) => c.channelName).join(", "),
-      );
-    }
+    debugLogger.debug(
+      "Auto-instrumentation active (ESM + CJS) for:",
+      allConfigs.map((c) => c.channelName).join(", "),
+    );
   } catch (err) {
     // CJS patch failed, but ESM hook is still active
-    if (process.env.DEBUG === "@braintrust*" || process.env.DEBUG === "*") {
-      console.log(
-        "[Braintrust] Auto-instrumentation active (ESM only) for:",
-        allConfigs.map((c) => c.channelName).join(", "),
-      );
-      console.error("[Braintrust] CJS patch failed:", err);
-    }
+    debugLogger.debug(
+      "Auto-instrumentation active (ESM only) for:",
+      allConfigs.map((c) => c.channelName).join(", "),
+    );
+    debugLogger.notice.error("CJS patch failed:", err);
   }
 }
diff --git a/js/src/auto-instrumentations/loader/cjs-patch.ts b/js/src/auto-instrumentations/loader/cjs-patch.ts
index 1a87b87a2..09c73987b 100644
--- a/js/src/auto-instrumentations/loader/cjs-patch.ts
+++ b/js/src/auto-instrumentations/loader/cjs-patch.ts
@@ -3,6 +3,8 @@
  * Patches Module.prototype._compile to transform CommonJS modules at load time.
  */
 
+import { debugLogger } from "../../debug-logger";
+
 import {
   InstrumentationMatcher,
   type InstrumentationConfig,
@@ -48,7 +50,10 @@ export function patchCommonJS(instrumentations: InstrumentationConfig[]): void {
           try {
             source = transformer.transform(source, "unknown").code;
           } catch (error) {
-            console.warn(`Error transforming module ${filename}:`, error);
+            debugLogger.notice.warn(
+              `Error transforming module ${filename}:`,
+              error,
+            );
           }
         }
       }
diff --git a/js/src/auto-instrumentations/loader/esm-hook.mts b/js/src/auto-instrumentations/loader/esm-hook.mts
index e966214e0..c4049670c 100644
--- a/js/src/auto-instrumentations/loader/esm-hook.mts
+++ b/js/src/auto-instrumentations/loader/esm-hook.mts
@@ -3,6 +3,8 @@
  * This is used by Node.js --import to transform ES modules at load time.
  */
 
+import { debugLogger } from "../../debug-logger.js";
+
 import { readFile } from "node:fs/promises";
 import { fileURLToPath } from "node:url";
 import { extname, sep } from "node:path";
@@ -89,7 +91,7 @@ export async function load(url: string, context: any, nextLoad: Function) {
       ).code;
       result.shortCircuit = true;
     } catch (err) {
-      console.warn(`Error transforming module ${url}:`, err);
+      debugLogger.notice.warn(`Error transforming module ${url}:`, err);
     }
   }
   return result;
diff --git a/js/src/debug-logger.test.ts b/js/src/debug-logger.test.ts
index d5a369fe5..88f29c051 100644
--- a/js/src/debug-logger.test.ts
+++ b/js/src/debug-logger.test.ts
@@ -16,6 +16,7 @@ import {
   login,
 } from "./logger";
 import { configureNode } from "./node/config";
+import iso from "./isomorph";
 
 configureNode();
 
@@ -94,6 +95,57 @@ describe("debug logger", () => {
     );
   });
 
+  test("notice messages are shown at warn when no level is configured", () => {
+    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+
+    debugLogger.warn("hidden warning");
+    expect(debugLogger.notice.warn("notice warning")).toBe(true);
+    expect(debugLogger.notice.error("notice error")).toBe(true);
+
+    expect(warnSpy).toHaveBeenCalledTimes(1);
+    expect(warnSpy).toHaveBeenCalledWith("[braintrust]", "notice warning");
+    expect(errorSpy).toHaveBeenCalledWith("[braintrust]", "notice error");
+  });
+
+  test("notice messages respect an explicit level", () => {
+    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    const state = {
+      getDebugLogLevel: () => "error" as const,
+      hasDebugLogLevelOverride: () => true,
+    };
+
+    const scopedLogger = debugLogger.forState(state);
+    expect(scopedLogger.notice.warn("notice warning")).toBe(false);
+    expect(scopedLogger.notice.error("notice error")).toBe(true);
+
+    expect(warnSpy).not.toHaveBeenCalled();
+    expect(errorSpy).toHaveBeenCalledWith("[braintrust]", "notice error");
+  });
+
+  test("notice messages are silenced when logging is disabled", () => {
+    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    _exportsForTestingOnly.setInitialTestState();
+    const state = _exportsForTestingOnly.simulateLogoutForTests();
+    state.setDebugLogLevel(false);
+
+    expect(debugLogger.notice.warn("notice warning")).toBe(false);
+    expect(debugLogger.notice.error("notice error")).toBe(false);
+    expect(
+      debugLogger
+        .forState({
+          getDebugLogLevel: () => undefined,
+          hasDebugLogLevelOverride: () => true,
+        })
+        .notice.error("scoped notice error"),
+    ).toBe(false);
+
+    expect(warnSpy).not.toHaveBeenCalled();
+    expect(errorSpy).not.toHaveBeenCalled();
+  });
+
   test("default logger resolves the global SDK state", () => {
     const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
     _exportsForTestingOnly.setInitialTestState();
@@ -105,7 +157,8 @@ describe("debug logger", () => {
     expect(warnSpy).toHaveBeenCalledWith("[braintrust]", "global warning");
   });
 
-  test("BRAINTRUST_DEBUG_LOG_LEVEL accepts error, warn, info, and debug", () => {
+  test("BRAINTRUST_DEBUG_LOG_LEVEL works before platform initialization", () => {
+    vi.spyOn(iso, "getEnv").mockReturnValue(undefined);
     process.env.BRAINTRUST_DEBUG_LOG_LEVEL = "error";
     expect(getEnvDebugLogLevel()).toBe("error");
 
@@ -119,6 +172,16 @@ describe("debug logger", () => {
     expect(getEnvDebugLogLevel()).toBe("debug");
   });
 
+  test("BRAINTRUST_DEBUG_LOG_LEVEL fallback tolerates a process shim without env", () => {
+    vi.spyOn(iso, "getEnv").mockReturnValue(undefined);
+    vi.stubGlobal("process", {});
+    try {
+      expect(getEnvDebugLogLevel()).toBeUndefined();
+    } finally {
+      vi.unstubAllGlobals();
+    }
+  });
+
   test("BRAINTRUST_DEBUG_LOG_LEVEL rejects invalid values and warns once", () => {
     const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
     process.env.BRAINTRUST_DEBUG_LOG_LEVEL = "true";
diff --git a/js/src/debug-logger.ts b/js/src/debug-logger.ts
index 24861c7f4..6b4b6b17c 100644
--- a/js/src/debug-logger.ts
+++ b/js/src/debug-logger.ts
@@ -9,11 +9,21 @@ type DebugLoggerStateLike = {
   hasDebugLogLevelOverride?: () => boolean;
 };
 
+// Notice methods return whether the message was emitted.
+type NoticeLoggerMethods = {
+  warn: (...args: unknown[]) => boolean;
+  error: (...args: unknown[]) => boolean;
+};
+
 type DebugLoggerMethods = {
   info: (...args: unknown[]) => void;
   debug: (...args: unknown[]) => void;
   warn: (...args: unknown[]) => void;
   error: (...args: unknown[]) => void;
+  // User-facing diagnostics that are shown at "warn" when no debug log level
+  // has been configured. An explicit level still filters them, and
+  // `debugLogLevel: false` silences them.
+  notice: NoticeLoggerMethods;
 };
 
 const PREFIX = "[braintrust]";
@@ -80,7 +90,13 @@ function parseDebugLogLevelEnv(
 }
 
 export function getEnvDebugLogLevel(): DebugLogLevel | undefined {
-  return parseDebugLogLevelEnv(iso.getEnv("BRAINTRUST_DEBUG_LOG_LEVEL"));
+  return parseDebugLogLevelEnv(
+    iso.getEnv("BRAINTRUST_DEBUG_LOG_LEVEL") ??
+      // Loader and bundler diagnostics can run before platform initialization.
+      (typeof process !== "undefined" && typeof process.env !== "undefined"
+        ? process.env.BRAINTRUST_DEBUG_LOG_LEVEL
+        : undefined),
+  );
 }
 
 export function setGlobalDebugLogLevel(
@@ -103,13 +119,15 @@ export function setDebugLogStateResolver(
   debugLogStateResolver = resolver;
 }
 
+// Returns `false` when logging was explicitly disabled and `undefined` when no
+// level has been configured.
 function resolveDebugLogLevel(
   state?: DebugLoggerStateLike,
-): DebugLogLevel | undefined {
+): DebugLogLevel | false | undefined {
   const stateLevel = state?.getDebugLogLevel?.();
   const hasStateOverride = state?.hasDebugLogLevelOverride?.() ?? false;
   if (hasStateOverride) {
-    return stateLevel;
+    return stateLevel ?? false;
   }
 
   const globalLevel =
@@ -119,7 +137,7 @@ function resolveDebugLogLevel(
     ] as DebugLogLevel | false | undefined;
 
   if (globalLevel !== undefined) {
-    return globalLevel === false ? undefined : globalLevel;
+    return globalLevel;
   }
 
   return getEnvDebugLogLevel();
@@ -129,11 +147,12 @@ function emit(
   method: "info" | "debug" | "warn" | "error",
   state: DebugLoggerStateLike | undefined,
   args: unknown[],
-) {
-  const level = resolveDebugLogLevel(state);
+  defaultLevel?: DebugLogLevel,
+): boolean {
+  const level = resolveDebugLogLevel(state) ?? defaultLevel;
 
   if (!level || LOG_LEVEL_PRIORITY[method] > LOG_LEVEL_PRIORITY[level]) {
-    return;
+    return false;
   }
 
   if (method === "info") {
@@ -149,6 +168,7 @@ function emit(
     // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
     console.error(PREFIX, ...args);
   }
+  return true;
 }
 
 function createDebugLogger(state?: DebugLoggerStateLike): DebugLoggerMethods {
@@ -166,6 +186,14 @@ function createDebugLogger(state?: DebugLoggerStateLike): DebugLoggerMethods {
     error(...args: unknown[]) {
       emit("error", resolveState(), args);
     },
+    notice: {
+      warn(...args: unknown[]) {
+        return emit("warn", resolveState(), args, "warn");
+      },
+      error(...args: unknown[]) {
+        return emit("error", resolveState(), args, "warn");
+      },
+    },
   };
 }
 
diff --git a/js/src/eval-parameters.ts b/js/src/eval-parameters.ts
index 7262cf2b7..433b9991b 100644
--- a/js/src/eval-parameters.ts
+++ b/js/src/eval-parameters.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "./debug-logger";
 import { z } from "zod/v3";
 import * as z4 from "zod/v4";
 import Ajv from "ajv";
@@ -125,8 +126,7 @@ function validateParametersWithZod<
           return [name, schema.parse(value)];
         }
       } catch (e) {
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.error("Error validating parameter", name, e);
+        debugLogger.notice.error("Error validating parameter", name, e);
         throw Error(
           `Invalid parameter '${name}': ${e instanceof Error ? e.message : String(e)}`,
         );
diff --git a/js/src/framework2.ts b/js/src/framework2.ts
index 22fff00ac..458f1d278 100644
--- a/js/src/framework2.ts
+++ b/js/src/framework2.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "./debug-logger";
 import { _initializeSpanContext } from "./framework";
 import type { Trace } from "./trace";
 import iso from "./isomorph";
@@ -128,16 +129,16 @@ export class Project {
 
   async publish() {
     if (globalThis._lazy_load) {
-      // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-      console.warn("publish() is a no-op when running `braintrust push`.");
+      debugLogger.notice.warn(
+        "publish() is a no-op when running `braintrust push`.",
+      );
       return;
     }
     await login();
     const projectMap = new ProjectNameIdMap();
     const functionDefinitions: FunctionEvent[] = [];
     if (this._publishableCodeFunctions.length > 0) {
-      // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-      console.warn(
+      debugLogger.notice.warn(
         "Code functions cannot be published directly. Use `braintrust push` instead.",
       );
     }
diff --git a/js/src/instrumentation/core/stream-patcher.test.ts b/js/src/instrumentation/core/stream-patcher.test.ts
index d357169f1..195fe7435 100644
--- a/js/src/instrumentation/core/stream-patcher.test.ts
+++ b/js/src/instrumentation/core/stream-patcher.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../debug-logger";
 import { describe, it, expect, vi } from "vitest";
 import {
   isAsyncIterable,
@@ -396,7 +397,7 @@ describe("patchStreamIfNeeded", () => {
       },
     });
 
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi.spyOn(debugLogger, "warn").mockImplementation(() => {});
     const onComplete = vi.fn();
 
     const result = patchStreamIfNeeded(stream, { onComplete });
@@ -416,7 +417,7 @@ describe("patchStreamIfNeeded", () => {
       },
     });
 
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi.spyOn(debugLogger, "warn").mockImplementation(() => {});
     const onComplete = vi.fn();
 
     const result = patchStreamIfNeeded(stream, { onComplete });
@@ -436,7 +437,9 @@ describe("patchStreamIfNeeded", () => {
       },
     };
 
-    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    const errorSpy = vi
+      .spyOn(debugLogger, "error")
+      .mockImplementation(() => {});
     const onComplete = vi.fn(() => {
       throw new Error("Handler error");
     });
@@ -464,7 +467,9 @@ describe("patchStreamIfNeeded", () => {
       },
     };
 
-    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    const errorSpy = vi
+      .spyOn(debugLogger, "error")
+      .mockImplementation(() => {});
     const onChunk = vi.fn(() => {
       throw new Error("Chunk handler error");
     });
@@ -493,7 +498,9 @@ describe("patchStreamIfNeeded", () => {
       },
     };
 
-    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    const errorSpy = vi
+      .spyOn(debugLogger, "error")
+      .mockImplementation(() => {});
     const onError = vi.fn(() => {
       throw new Error("Error handler error");
     });
@@ -678,7 +685,9 @@ describe("wrapStreamResult", () => {
       },
     };
 
-    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    const errorSpy = vi
+      .spyOn(debugLogger, "error")
+      .mockImplementation(() => {});
     const processChunks = vi.fn(() => {
       throw new Error("Process error");
     });
@@ -709,7 +718,9 @@ describe("wrapStreamResult", () => {
   it("should handle errors in onNonStream", () => {
     const result = { foo: "bar" };
 
-    const errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    const errorSpy = vi
+      .spyOn(debugLogger, "error")
+      .mockImplementation(() => {});
     const processChunks = vi.fn();
     const onNonStream = vi.fn(() => {
       throw new Error("Non-stream error");
diff --git a/js/src/instrumentation/core/stream-patcher.ts b/js/src/instrumentation/core/stream-patcher.ts
index d9d77738a..a9aa483e7 100644
--- a/js/src/instrumentation/core/stream-patcher.ts
+++ b/js/src/instrumentation/core/stream-patcher.ts
@@ -152,8 +152,7 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
 
   // Check if object is extensible (can be patched)
   if (Object.isFrozen(stream) || Object.isSealed(stream)) {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn(
+    debugLogger.warn(
       "Cannot patch frozen/sealed stream. Stream output will not be collected.",
     );
     return stream;
@@ -222,8 +221,7 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
               try {
                 await options.onComplete(chunks);
               } catch (error) {
-                // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                console.error("Error in stream onComplete handler:", error);
+                debugLogger.error("Error in stream onComplete handler:", error);
               }
             }
           } else {
@@ -239,8 +237,7 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
                 try {
                   await options.onChunk(chunk);
                 } catch (error) {
-                  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                  console.error("Error in stream onChunk handler:", error);
+                  debugLogger.error("Error in stream onChunk handler:", error);
                 }
               }
             }
@@ -257,8 +254,10 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
                   chunks,
                 );
               } catch (handlerError) {
-                // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                console.error("Error in stream onError handler:", handlerError);
+                debugLogger.error(
+                  "Error in stream onError handler:",
+                  handlerError,
+                );
               }
             }
           }
@@ -289,8 +288,10 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
               try {
                 await options.onError(error, chunks);
               } catch (handlerError) {
-                // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                console.error("Error in stream onError handler:", handlerError);
+                debugLogger.error(
+                  "Error in stream onError handler:",
+                  handlerError,
+                );
               }
             }
           }
@@ -305,8 +306,7 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
       patchAbortIfPresent();
       return stream;
     } catch (error) {
-      // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-      console.warn("Failed to patch stream iterator methods:", error);
+      debugLogger.warn("Failed to patch stream iterator methods:", error);
     }
   }
 
@@ -340,8 +340,7 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
               try {
                 await options.onComplete(chunks);
               } catch (error) {
-                // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                console.error("Error in stream onComplete handler:", error);
+                debugLogger.error("Error in stream onComplete handler:", error);
               }
             }
           } else {
@@ -361,8 +360,7 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
                 try {
                   await options.onChunk(chunk);
                 } catch (error) {
-                  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                  console.error("Error in stream onChunk handler:", error);
+                  debugLogger.error("Error in stream onChunk handler:", error);
                 }
               }
             }
@@ -380,8 +378,10 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
                   chunks,
                 );
               } catch (handlerError) {
-                // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                console.error("Error in stream onError handler:", handlerError);
+                debugLogger.error(
+                  "Error in stream onError handler:",
+                  handlerError,
+                );
               }
             }
           }
@@ -416,8 +416,10 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
               try {
                 await options.onError(error, chunks);
               } catch (handlerError) {
-                // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                console.error("Error in stream onError handler:", handlerError);
+                debugLogger.error(
+                  "Error in stream onError handler:",
+                  handlerError,
+                );
               }
             }
           }
@@ -440,8 +442,7 @@ export function patchStreamIfNeeded<TChunk = unknown, TFinal = unknown>(
     return stream;
   } catch (error) {
     // If patching fails for any reason, log warning and return original
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Failed to patch stream:", error);
+    debugLogger.warn("Failed to patch stream:", error);
     return stream;
   }
 }
@@ -765,8 +766,7 @@ export function wrapStreamResult<TChunk = unknown, TProcessed = unknown>(
           const processed = options.processChunks(chunks);
           options.onResult(processed);
         } catch (error) {
-          // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-          console.error("Error processing stream chunks:", error);
+          debugLogger.error("Error processing stream chunks:", error);
           if (options.onError) {
             options.onError(
               error instanceof Error ? error : new Error(String(error)),
@@ -786,8 +786,7 @@ export function wrapStreamResult<TChunk = unknown, TProcessed = unknown>(
         : result;
       options.onResult(processed);
     } catch (error) {
-      // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-      console.error("Error processing non-stream result:", error);
+      debugLogger.error("Error processing non-stream result:", error);
       if (options.onError) {
         options.onError(
           error instanceof Error ? error : new Error(String(error)),
diff --git a/js/src/instrumentation/plugins/ai-sdk-plugin.ts b/js/src/instrumentation/plugins/ai-sdk-plugin.ts
index 267defb73..d45e0edb4 100644
--- a/js/src/instrumentation/plugins/ai-sdk-plugin.ts
+++ b/js/src/instrumentation/plugins/ai-sdk-plugin.ts
@@ -1906,8 +1906,7 @@ const processContentPart = (part: any): any => {
       }
     }
   } catch (error) {
-    // eslint-disable-next-line no-restricted-properties
-    console.warn("Error processing content part:", error);
+    debugLogger.warn("Error processing content part:", error);
   }
 
   return part;
@@ -1956,8 +1955,7 @@ const convertImageToAttachment = (
       return image;
     }
   } catch (error) {
-    // eslint-disable-next-line no-restricted-properties
-    console.warn("Error converting image to attachment:", error);
+    debugLogger.warn("Error converting image to attachment:", error);
   }
 
   return null;
@@ -1996,8 +1994,7 @@ const convertDataToAttachment = (
       });
     }
   } catch (error) {
-    // eslint-disable-next-line no-restricted-properties
-    console.warn("Error converting data to attachment:", error);
+    debugLogger.warn("Error converting data to attachment:", error);
   }
 
   return null;
diff --git a/js/src/instrumentation/plugins/claude-agent-sdk-plugin.ts b/js/src/instrumentation/plugins/claude-agent-sdk-plugin.ts
index f4321935a..17c2f1db9 100644
--- a/js/src/instrumentation/plugins/claude-agent-sdk-plugin.ts
+++ b/js/src/instrumentation/plugins/claude-agent-sdk-plugin.ts
@@ -1845,8 +1845,10 @@ export class ClaudeAgentSDKPlugin extends BasePlugin {
           metadata: filterSerializableOptions(options),
         });
       } catch (error) {
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.error("Error extracting input for Claude Agent SDK:", error);
+        debugLogger.error(
+          "Error extracting input for Claude Agent SDK:",
+          error,
+        );
       }
 
       const activeToolSpans = new Map<string, Span>();
@@ -1982,8 +1984,7 @@ export class ClaudeAgentSDKPlugin extends BasePlugin {
             state.processing = state.processing
               .then(() => handleStreamMessage(state, message))
               .catch((error) => {
-                // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-                console.error(
+                debugLogger.error(
                   "Error processing Claude Agent SDK stream chunk:",
                   error,
                 );
@@ -2005,8 +2006,10 @@ export class ClaudeAgentSDKPlugin extends BasePlugin {
       try {
         state.span.log({ output: result });
       } catch (error) {
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.error("Error extracting output for Claude Agent SDK:", error);
+        debugLogger.error(
+          "Error extracting output for Claude Agent SDK:",
+          error,
+        );
       } finally {
         state.span.end();
       }
diff --git a/js/src/instrumentation/plugins/github-copilot-plugin.ts b/js/src/instrumentation/plugins/github-copilot-plugin.ts
index dcc172879..a8e43a085 100644
--- a/js/src/instrumentation/plugins/github-copilot-plugin.ts
+++ b/js/src/instrumentation/plugins/github-copilot-plugin.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../debug-logger";
 import { SpanTypeAttribute } from "../../../util/index";
 import type { Span } from "../../logger";
 import { startSpan as startBaseSpan } from "../../logger";
@@ -650,11 +651,7 @@ function attachSessionEventListener(
     state.processing = state.processing
       .then(() => dispatchEvent(state, event))
       .catch((err) => {
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.error(
-          "[Braintrust] Error processing GitHub Copilot SDK event:",
-          err,
-        );
+        debugLogger.error("Error processing GitHub Copilot SDK event:", err);
       });
   };
 
diff --git a/js/src/instrumentation/registry.test.ts b/js/src/instrumentation/registry.test.ts
index fb8707de4..47d2196e9 100644
--- a/js/src/instrumentation/registry.test.ts
+++ b/js/src/instrumentation/registry.test.ts
@@ -1,5 +1,6 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { newGlobalInvocationHook } from "../global-instrumentation-hooks";
+import { debugLogger } from "../debug-logger";
 vi.mock("../global-instrumentation-hooks", async (importOriginal) => ({
   ...(await importOriginal<typeof import("../global-instrumentation-hooks")>()),
   newGlobalInvocationHook: vi.fn(),
@@ -108,35 +109,36 @@ describe("Plugin Registry", () => {
 
   it("should warn if configureInstrumentation is called after enable", () => {
     const testRegistry = new (registry.constructor as any)();
-    const warnSpy = [] as string[];
-    const originalWarn = console.warn;
-    console.warn = (msg: string) => warnSpy.push(msg);
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
 
     try {
       testRegistry.enable();
       testRegistry.configure({ integrations: { openai: false } });
 
-      expect(warnSpy.length).toBeGreaterThan(0);
-      expect(warnSpy[0]).toContain("Cannot configure instrumentation");
+      expect(warnSpy).toHaveBeenCalledWith(
+        expect.stringContaining("Cannot configure instrumentation"),
+      );
     } finally {
-      console.warn = originalWarn;
+      warnSpy.mockRestore();
       testRegistry.disable();
     }
   });
 
   it("should allow configuration before enable", () => {
     const testRegistry = new (registry.constructor as any)();
-    const warnSpy = [] as string[];
-    const originalWarn = console.warn;
-    console.warn = (msg: string) => warnSpy.push(msg);
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
 
     try {
       testRegistry.configure({ integrations: { openai: false } });
       testRegistry.enable();
 
-      expect(warnSpy.length).toBe(0);
+      expect(warnSpy).not.toHaveBeenCalled();
     } finally {
-      console.warn = originalWarn;
+      warnSpy.mockRestore();
       testRegistry.disable();
     }
   });
diff --git a/js/src/instrumentation/registry.ts b/js/src/instrumentation/registry.ts
index 9fbc5b79b..ce15a7fac 100644
--- a/js/src/instrumentation/registry.ts
+++ b/js/src/instrumentation/registry.ts
@@ -5,6 +5,8 @@
  * Users can disable specific integrations programmatically or via environment variables.
  */
 
+import { debugLogger } from "../debug-logger";
+
 import { BraintrustPlugin } from "./braintrust-plugin";
 import iso from "../isomorph";
 import {
@@ -55,9 +57,8 @@ class PluginRegistry {
    */
   configure(config: InstrumentationConfig): void {
     if (this.enabled) {
-      // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-      console.warn(
-        "Braintrust: Cannot configure instrumentation after it has been enabled. " +
+      debugLogger.notice.warn(
+        "Cannot configure instrumentation after it has been enabled. " +
           "Call configureInstrumentation() before importing any AI SDKs.",
       );
       return;
diff --git a/js/src/prompt-cache/disk-cache.ts b/js/src/prompt-cache/disk-cache.ts
index 8d5dc256c..79ccd385f 100644
--- a/js/src/prompt-cache/disk-cache.ts
+++ b/js/src/prompt-cache/disk-cache.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import iso from "../isomorph";
 
 export function canUseDiskCache(): boolean {
@@ -96,8 +97,7 @@ export class DiskCache<T> {
         return undefined;
       }
       if (this.logWarnings) {
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.warn("Failed to read from disk cache", e);
+        debugLogger.warn("Failed to read from disk cache", e);
       }
       return undefined;
     }
@@ -122,8 +122,7 @@ export class DiskCache<T> {
       await this.evictOldestIfFull();
     } catch (e) {
       if (this.logWarnings) {
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.warn("Failed to write to disk cache", e);
+        debugLogger.warn("Failed to write to disk cache", e);
       }
       return;
     }
diff --git a/js/src/span-customizer.test.ts b/js/src/span-customizer.test.ts
index 954d46c7a..fa3ad721f 100644
--- a/js/src/span-customizer.test.ts
+++ b/js/src/span-customizer.test.ts
@@ -48,6 +48,7 @@ describe("onSpanExport", () => {
   let memoryLogger: TestBackgroundLogger;
 
   beforeEach(async () => {
+    vi.stubEnv("BRAINTRUST_DEBUG_LOG_LEVEL", "error");
     registry.disable();
     await _exportsForTestingOnly.simulateLoginForTests();
     memoryLogger = _exportsForTestingOnly.useTestBackgroundLogger();
@@ -833,6 +834,34 @@ describe("onSpanExport", () => {
     }
   });
 
+  test("logs the failure once logging is enabled after a silenced failure", () => {
+    const errorLog = vi.spyOn(console, "error").mockImplementation(() => {});
+    const state = _internalGetGlobalState();
+    configureInstrumentation({
+      spanCustomizers: [
+        {
+          onSpanExport(): SpanExportData {
+            throw new Error("private exception detail");
+          },
+        },
+      ],
+    });
+
+    state.setDebugLogLevel(false);
+    customizeSpanExport({ id: "silenced" });
+    expect(errorLog).not.toHaveBeenCalled();
+
+    state.setDebugLogLevel("error");
+    customizeSpanExport({ id: "visible" });
+    customizeSpanExport({ id: "deduplicated" });
+    expect(errorLog.mock.calls).toEqual([
+      [
+        "[braintrust]",
+        "Span export customizer failed; exporting only span identity and duration.",
+      ],
+    ]);
+  });
+
   test("logs safely once across time, registrations, and SDK module copies", async () => {
     vi.useFakeTimers({ toFake: ["Date"] });
     const errorLog = vi.spyOn(console, "error").mockImplementation(() => {});
@@ -863,7 +892,8 @@ describe("onSpanExport", () => {
     expect(errorLog).toHaveBeenCalledTimes(1);
     expect(errorLog.mock.calls).toEqual([
       [
-        "[braintrust] Span export customizer failed; exporting only span identity and duration.",
+        "[braintrust]",
+        "Span export customizer failed; exporting only span identity and duration.",
       ],
     ]);
   });
diff --git a/js/src/span-customizer.ts b/js/src/span-customizer.ts
index a86eda4df..802d4c829 100644
--- a/js/src/span-customizer.ts
+++ b/js/src/span-customizer.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "./debug-logger";
 import {
   ARRAY_DELETE_FIELD,
   ID_FIELD,
@@ -152,12 +153,15 @@ function restoreProtocolFields(
 
 function registerCustomizerFailure(): void {
   if (shared[CUSTOMIZER_FAILURE_LOGGED_KEY]) return;
-  shared[CUSTOMIZER_FAILURE_LOGGED_KEY] = true;
   // Never log the exception or record: either can contain sensitive data.
-  // eslint-disable-next-line no-restricted-properties -- intentional always-visible export failure.
-  console.error(
-    "[braintrust] Span export customizer failed; exporting only span identity and duration.",
-  );
+  // Only mark as logged once emitted so enabling logging later still surfaces it.
+  if (
+    debugLogger.notice.error(
+      "Span export customizer failed; exporting only span identity and duration.",
+    )
+  ) {
+    shared[CUSTOMIZER_FAILURE_LOGGED_KEY] = true;
+  }
 }
 
 export function resetSpanCustomizerFailureLoggingForTests(): void {
diff --git a/js/src/template/registry.ts b/js/src/template/registry.ts
index 6ebcace61..d9744e8a4 100644
--- a/js/src/template/registry.ts
+++ b/js/src/template/registry.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { mustachePlugin } from "./plugins/mustache";
 
 export type TemplateFormat = "mustache" | "nunjucks" | "none";
@@ -67,8 +68,7 @@ class TemplatePluginRegistry {
 
   register(plugin: TemplateRendererPlugin): void {
     if (this.plugins.has(plugin.name)) {
-      // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-      console.warn(
+      debugLogger.warn(
         `Template plugin '${plugin.name}' already registered, overwriting`,
       );
     }
diff --git a/js/src/wrappers/ai-sdk/deprecated/wrapAISDKModel.ts b/js/src/wrappers/ai-sdk/deprecated/wrapAISDKModel.ts
index 705048346..f28764813 100644
--- a/js/src/wrappers/ai-sdk/deprecated/wrapAISDKModel.ts
+++ b/js/src/wrappers/ai-sdk/deprecated/wrapAISDKModel.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../../debug-logger";
 /* eslint-disable @typescript-eslint/consistent-type-assertions */
 /* eslint-disable @typescript-eslint/no-explicit-any */
 import { startSpan } from "../../../logger";
@@ -29,8 +30,7 @@ export function wrapAISDKModel<T extends object>(model: T): T {
   ) {
     return new BraintrustLanguageModelWrapper(m) as any as T;
   } else {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported AI SDK model. Not wrapping.");
+    debugLogger.notice.warn("Unsupported AI SDK model. Not wrapping.");
     return model;
   }
 }
diff --git a/js/src/wrappers/ai-sdk/telemetry.ts b/js/src/wrappers/ai-sdk/telemetry.ts
index 08f2989b8..12f60a9f2 100644
--- a/js/src/wrappers/ai-sdk/telemetry.ts
+++ b/js/src/wrappers/ai-sdk/telemetry.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../debug-logger";
 import { isAutoInstrumentationSuppressed } from "../../instrumentation/auto-instrumentation-suppression";
 import {
   SpanTypeAttribute,
@@ -93,8 +94,7 @@ export function braintrustAISDKTelemetry(): any {
     try {
       callback();
     } catch (error) {
-      // eslint-disable-next-line no-restricted-properties
-      console.error(`Error in Braintrust AI SDK telemetry ${name}:`, error);
+      debugLogger.error(`Error in Braintrust AI SDK telemetry ${name}:`, error);
     }
   };
 
diff --git a/js/src/wrappers/anthropic.ts b/js/src/wrappers/anthropic.ts
index 43d1b6471..e98f9b12f 100644
--- a/js/src/wrappers/anthropic.ts
+++ b/js/src/wrappers/anthropic.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { anthropicChannels } from "../instrumentation/plugins/anthropic-interceptors";
 import { TypedApplyProxy } from "../typed-instrumentation-helpers";
 import type {
@@ -38,8 +39,7 @@ export function wrapAnthropic<T extends object>(anthropic: T): T {
     return anthropicProxy(au as AnthropicClient) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported Anthropic library. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Anthropic library. Not wrapping.");
   return anthropic;
 }
 
diff --git a/js/src/wrappers/bedrock-runtime.test.ts b/js/src/wrappers/bedrock-runtime.test.ts
index e2a8d606a..4da0d27c5 100644
--- a/js/src/wrappers/bedrock-runtime.test.ts
+++ b/js/src/wrappers/bedrock-runtime.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import {
   afterEach,
   beforeAll,
@@ -56,7 +57,9 @@ describe("bedrock runtime wrapper", () => {
   });
 
   test("returns original object for unsupported clients", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const invalid = { foo: "bar" };
 
     expect(wrapBedrockRuntime(invalid)).toBe(invalid);
diff --git a/js/src/wrappers/bedrock-runtime.ts b/js/src/wrappers/bedrock-runtime.ts
index 38efbf3ee..3919553cc 100644
--- a/js/src/wrappers/bedrock-runtime.ts
+++ b/js/src/wrappers/bedrock-runtime.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { runWithAutoInstrumentationSuppressed } from "../instrumentation/auto-instrumentation-suppression";
 import { bedrockRuntimeChannels } from "../instrumentation/plugins/bedrock-runtime-interceptors";
 import {
@@ -17,8 +18,7 @@ export function wrapBedrockRuntime<T>(client: T): T {
     return bedrockRuntimeProxy(client) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving wrapper warning behavior.
-  console.warn("Unsupported Bedrock Runtime library. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Bedrock Runtime library. Not wrapping.");
   return client;
 }
 
diff --git a/js/src/wrappers/claude-agent-sdk/claude-agent-sdk.ts b/js/src/wrappers/claude-agent-sdk/claude-agent-sdk.ts
index ac80bc297..4ed523dd3 100644
--- a/js/src/wrappers/claude-agent-sdk/claude-agent-sdk.ts
+++ b/js/src/wrappers/claude-agent-sdk/claude-agent-sdk.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../debug-logger";
 import { claudeAgentSDKChannels } from "../../instrumentation/plugins/claude-agent-sdk-interceptors";
 import { CLAUDE_AGENT_SDK_SKIP_LOCAL_TOOL_HOOKS_OPTION } from "../../instrumentation/plugins/claude-agent-sdk-instrumentation-constants";
 import { wrapLocalClaudeToolHandler } from "../../instrumentation/plugins/claude-agent-sdk-local-tool-spans";
@@ -31,8 +32,7 @@ export function wrapClaudeAgentSDK<T extends object>(sdk: T): T {
     return claudeAgentSDKProxy(s as ClaudeAgentSDKModule) as unknown as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported Claude Agent SDK. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Claude Agent SDK. Not wrapping.");
   return sdk;
 }
 
diff --git a/js/src/wrappers/cloudflare-agent.ts b/js/src/wrappers/cloudflare-agent.ts
index 8825113a3..4930a5185 100644
--- a/js/src/wrappers/cloudflare-agent.ts
+++ b/js/src/wrappers/cloudflare-agent.ts
@@ -86,5 +86,7 @@ function isObjectLike(value: unknown): value is object {
 }
 
 function warnUnsupportedAgent(): void {
-  debugLogger.warn("Unsupported Cloudflare Agents Agent class. Not wrapping.");
+  debugLogger.notice.warn(
+    "Unsupported Cloudflare Agents Agent class. Not wrapping.",
+  );
 }
diff --git a/js/src/wrappers/cloudflare-ai-chat.ts b/js/src/wrappers/cloudflare-ai-chat.ts
index 87df27775..4023bbb49 100644
--- a/js/src/wrappers/cloudflare-ai-chat.ts
+++ b/js/src/wrappers/cloudflare-ai-chat.ts
@@ -30,7 +30,7 @@ export function wrapCloudflareAIChat<T>(module: T): T {
   }
 
   if (typeof AIChatAgent !== "function") {
-    debugLogger.warn(
+    debugLogger.notice.warn(
       "Unsupported @cloudflare/ai-chat module. AIChatAgent was not found; not wrapping.",
     );
     return module;
diff --git a/js/src/wrappers/cohere.test.ts b/js/src/wrappers/cohere.test.ts
index 5c585b948..9f580d166 100644
--- a/js/src/wrappers/cohere.test.ts
+++ b/js/src/wrappers/cohere.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import {
   afterEach,
   beforeAll,
@@ -40,7 +41,9 @@ describe("cohere wrapper", () => {
   });
 
   test("returns original object for unsupported clients", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const invalid = { foo: "bar" };
 
     expect(wrapCohere(invalid)).toBe(invalid);
diff --git a/js/src/wrappers/cohere.ts b/js/src/wrappers/cohere.ts
index 7f3d84405..a91a8b094 100644
--- a/js/src/wrappers/cohere.ts
+++ b/js/src/wrappers/cohere.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { cohereChannels } from "../instrumentation/plugins/cohere-interceptors";
 import type {
   CohereChatRequest,
@@ -19,8 +20,7 @@ export function wrapCohere<T>(cohere: T): T {
     return cohereProxy(cohere) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported Cohere library. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Cohere library. Not wrapping.");
   return cohere;
 }
 
diff --git a/js/src/wrappers/cursor-sdk.test.ts b/js/src/wrappers/cursor-sdk.test.ts
index 8a63363a9..b260e4a1d 100644
--- a/js/src/wrappers/cursor-sdk.test.ts
+++ b/js/src/wrappers/cursor-sdk.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { afterEach, describe, expect, it, vi } from "vitest";
 
 const { invoke } = vi.hoisted(() => ({
@@ -23,7 +24,9 @@ describe("wrapCursorSDK", () => {
   });
 
   it("returns invalid modules unchanged", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const sdk = { Cursor: {} };
 
     expect(wrapCursorSDK(sdk)).toBe(sdk);
diff --git a/js/src/wrappers/cursor-sdk.ts b/js/src/wrappers/cursor-sdk.ts
index 2188066e0..a2ec37d60 100644
--- a/js/src/wrappers/cursor-sdk.ts
+++ b/js/src/wrappers/cursor-sdk.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { cursorSDKChannels } from "../instrumentation/plugins/cursor-sdk-interceptors";
 import type {
   CursorSDKAgent,
@@ -21,8 +22,7 @@ export function wrapCursorSDK<T>(sdk: T): T {
 
   const maybeSDK = sdk as Record<PropertyKey, unknown>;
   if (!maybeSDK.Agent || typeof maybeSDK.Agent !== "function") {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported Cursor SDK. Not wrapping.");
+    debugLogger.notice.warn("Unsupported Cursor SDK. Not wrapping.");
     return sdk;
   }
 
diff --git a/js/src/wrappers/elevenlabs.ts b/js/src/wrappers/elevenlabs.ts
index 01700532c..b106e3422 100644
--- a/js/src/wrappers/elevenlabs.ts
+++ b/js/src/wrappers/elevenlabs.ts
@@ -30,7 +30,7 @@ export function wrapElevenLabs<T>(client: T): T {
     !isObject(client.textToSpeech) ||
     typeof client.textToSpeech.convert !== "function"
   ) {
-    debugLogger.warn("Unsupported ElevenLabs client. Not wrapping.");
+    debugLogger.notice.warn("Unsupported ElevenLabs client. Not wrapping.");
     return client;
   }
   const cached = clients.get(client);
diff --git a/js/src/wrappers/genkit.ts b/js/src/wrappers/genkit.ts
index eea037b25..47cbcd384 100644
--- a/js/src/wrappers/genkit.ts
+++ b/js/src/wrappers/genkit.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { genkitChannels } from "../instrumentation/plugins/genkit-interceptors";
 import type {
   GenkitAction,
@@ -36,8 +37,7 @@ export function wrapGenkit<T>(genkit: T): T {
     return wrapGenkitModule(genkit) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported Genkit object. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Genkit object. Not wrapping.");
   return genkit;
 }
 
diff --git a/js/src/wrappers/github-copilot.ts b/js/src/wrappers/github-copilot.ts
index 249f9b71c..4faf0fd43 100644
--- a/js/src/wrappers/github-copilot.ts
+++ b/js/src/wrappers/github-copilot.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { gitHubCopilotChannels } from "../instrumentation/plugins/github-copilot-interceptors";
 import type {
   GitHubCopilotClient,
@@ -37,9 +38,8 @@ function isGitHubCopilotClient(value: unknown): value is GitHubCopilotClient {
  */
 export function wrapCopilotClient<T extends object>(client: T): T {
   if (!isGitHubCopilotClient(client)) {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn(
-      "[Braintrust] wrapCopilotClient: argument does not look like a CopilotClient. Not wrapping.",
+    debugLogger.notice.warn(
+      "wrapCopilotClient: argument does not look like a CopilotClient. Not wrapping.",
     );
     return client;
   }
diff --git a/js/src/wrappers/google-adk.test.ts b/js/src/wrappers/google-adk.test.ts
index 77256f6ba..67de8a16b 100644
--- a/js/src/wrappers/google-adk.test.ts
+++ b/js/src/wrappers/google-adk.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { describe, it, expect, vi, afterEach } from "vitest";
 
 const { invoke } = vi.hoisted(() => ({
@@ -23,7 +24,9 @@ describe("wrapGoogleADK", () => {
   });
 
   it("should return the module unchanged if invalid", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
 
     const result = wrapGoogleADK(null as any);
     expect(result).toBeNull();
@@ -35,7 +38,9 @@ describe("wrapGoogleADK", () => {
   });
 
   it("should return module unchanged if no Runner or LlmAgent found", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
 
     const fakeModule = { SomeOtherClass: class {} };
     const result = wrapGoogleADK(fakeModule as any);
diff --git a/js/src/wrappers/google-adk.ts b/js/src/wrappers/google-adk.ts
index 4a22203f8..875ce4ca4 100644
--- a/js/src/wrappers/google-adk.ts
+++ b/js/src/wrappers/google-adk.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { googleADKChannels } from "../instrumentation/plugins/google-adk-interceptors";
 import type {
   GoogleADKBaseAgent,
@@ -41,14 +42,12 @@ import type {
  */
 export function wrapGoogleADK<T extends Record<string, any>>(adkModule: T): T {
   if (!adkModule || typeof adkModule !== "object") {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Invalid Google ADK module. Not wrapping.");
+    debugLogger.notice.warn("Invalid Google ADK module. Not wrapping.");
     return adkModule;
   }
 
   if (!("Runner" in adkModule) && !("LlmAgent" in adkModule)) {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn(
+    debugLogger.notice.warn(
       "Runner or LlmAgent class not found in module. Not wrapping. Make sure you're passing the module itself (import * as adk from '@google/adk').",
     );
     return adkModule;
diff --git a/js/src/wrappers/google-genai.ts b/js/src/wrappers/google-genai.ts
index b4e0c5bb7..f9ed4917c 100644
--- a/js/src/wrappers/google-genai.ts
+++ b/js/src/wrappers/google-genai.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { googleGenAIChannels } from "../instrumentation/plugins/google-genai-interceptors";
 import { isObject } from "../util";
 import type {
@@ -37,14 +38,12 @@ export function wrapGoogleGenAI<T extends Record<string, any>>(
   googleGenAI: T,
 ): T {
   if (!googleGenAI || typeof googleGenAI !== "object") {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Invalid Google GenAI module. Not wrapping.");
+    debugLogger.notice.warn("Invalid Google GenAI module. Not wrapping.");
     return googleGenAI;
   }
 
   if (!("GoogleGenAI" in googleGenAI)) {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn(
+    debugLogger.notice.warn(
       "GoogleGenAI class not found in module. Not wrapping. Make sure you're passing the module itself (import * as googleGenAI from '@google/genai').",
     );
     return googleGenAI;
diff --git a/js/src/wrappers/groq.test.ts b/js/src/wrappers/groq.test.ts
index d44daf491..88a6c0f95 100644
--- a/js/src/wrappers/groq.test.ts
+++ b/js/src/wrappers/groq.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import {
   afterEach,
   beforeAll,
@@ -41,7 +42,9 @@ describe("groq wrapper", () => {
   });
 
   test("returns original object for unsupported clients", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const invalid = { foo: "bar" };
 
     expect(wrapGroq(invalid)).toBe(invalid);
diff --git a/js/src/wrappers/groq.ts b/js/src/wrappers/groq.ts
index 6f71b7e76..488efdd6d 100644
--- a/js/src/wrappers/groq.ts
+++ b/js/src/wrappers/groq.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { groqChannels } from "../instrumentation/plugins/groq-interceptors";
 import type {
   GroqAudio,
@@ -22,8 +23,7 @@ export function wrapGroq<T extends object>(groq: T): T {
     return groqProxy(groq) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported Groq library. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Groq library. Not wrapping.");
   return groq;
 }
 
diff --git a/js/src/wrappers/huggingface.ts b/js/src/wrappers/huggingface.ts
index 80272ac56..c01e0756c 100644
--- a/js/src/wrappers/huggingface.ts
+++ b/js/src/wrappers/huggingface.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { isObject } from "../../util";
 import { huggingFaceChannels } from "../instrumentation/plugins/huggingface-interceptors";
 import type {
@@ -51,8 +52,9 @@ export function wrapHuggingFace(huggingFace: unknown): unknown {
     return clientProxy(huggingFace);
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported HuggingFace Inference SDK. Not wrapping.");
+  debugLogger.notice.warn(
+    "Unsupported HuggingFace Inference SDK. Not wrapping.",
+  );
   return huggingFace;
 }
 
diff --git a/js/src/wrappers/langgraph-sdk.ts b/js/src/wrappers/langgraph-sdk.ts
index 5c82a13b6..6c33b6487 100644
--- a/js/src/wrappers/langgraph-sdk.ts
+++ b/js/src/wrappers/langgraph-sdk.ts
@@ -13,7 +13,7 @@ export function wrapLangGraphSDK<T>(client: T): T {
     !isObject(runsClient) ||
     !["wait", "stream"].every((key) => typeof runsClient[key] === "function")
   ) {
-    debugLogger.warn("Unsupported LangGraph SDK client. Not wrapping.");
+    debugLogger.notice.warn("Unsupported LangGraph SDK client. Not wrapping.");
     return client;
   }
   const sdk = client as unknown as LangGraphSDKClient;
diff --git a/js/src/wrappers/langsmith.ts b/js/src/wrappers/langsmith.ts
index b5d0ab37f..5213d5366 100644
--- a/js/src/wrappers/langsmith.ts
+++ b/js/src/wrappers/langsmith.ts
@@ -74,8 +74,7 @@ function wrapNamespaceExport<T>(
     return namespace;
   }
   if (typeof candidate[exportName] !== "function") {
-    // eslint-disable-next-line no-restricted-properties -- public wrapper diagnostics follow existing wrapper behavior.
-    console.warn(
+    debugLogger.notice.warn(
       `Unsupported LangSmith ${exportName} namespace. Not wrapping.`,
     );
     return namespace;
diff --git a/js/src/wrappers/mistral.ts b/js/src/wrappers/mistral.ts
index 9bdcece10..af5003074 100644
--- a/js/src/wrappers/mistral.ts
+++ b/js/src/wrappers/mistral.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { mistralChannels } from "../instrumentation/plugins/mistral-interceptors";
 import type {
   MistralAgents,
@@ -31,8 +32,7 @@ export function wrapMistral<T>(mistral: T): T {
     return mistralProxy(mistral) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported Mistral library. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Mistral library. Not wrapping.");
   return mistral;
 }
 
diff --git a/js/src/wrappers/oai.ts b/js/src/wrappers/oai.ts
index 787517a41..d49800de9 100644
--- a/js/src/wrappers/oai.ts
+++ b/js/src/wrappers/oai.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import type {
   OpenAIMediaClient,
   OpenAIMediaMethod,
@@ -68,8 +69,9 @@ export function wrapOpenAI<T extends object>(openai: T): T {
     // eslint-disable-next-line @typescript-eslint/consistent-type-assertions
     return wrapOpenAIv4(typedOpenAI) as T;
   } else {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported OpenAI library (potentially v3). Not wrapping.");
+    debugLogger.notice.warn(
+      "Unsupported OpenAI library (potentially v3). Not wrapping.",
+    );
     return openai;
   }
 }
diff --git a/js/src/wrappers/ollama.test.ts b/js/src/wrappers/ollama.test.ts
index 9b368166e..2db63e5eb 100644
--- a/js/src/wrappers/ollama.test.ts
+++ b/js/src/wrappers/ollama.test.ts
@@ -52,7 +52,9 @@ describe("wrapOllama", () => {
 
   it("returns unsupported objects unchanged", () => {
     const client = {};
-    const warn = vi.spyOn(debugLogger, "warn").mockImplementation(() => {});
+    const warn = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
 
     expect(wrapOllama(client)).toBe(client);
     expect(warn).toHaveBeenCalledWith(
diff --git a/js/src/wrappers/ollama.ts b/js/src/wrappers/ollama.ts
index 8f20da200..c5b9a5faa 100644
--- a/js/src/wrappers/ollama.ts
+++ b/js/src/wrappers/ollama.ts
@@ -20,7 +20,7 @@ export function wrapOllama<T>(ollama: T): T {
     return ollamaProxy(ollama) as T;
   }
 
-  debugLogger.warn("Unsupported Ollama library. Not wrapping.");
+  debugLogger.notice.warn("Unsupported Ollama library. Not wrapping.");
   return ollama;
 }
 
diff --git a/js/src/wrappers/openai-codex.ts b/js/src/wrappers/openai-codex.ts
index 901bc855e..ced9c7708 100644
--- a/js/src/wrappers/openai-codex.ts
+++ b/js/src/wrappers/openai-codex.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { openAICodexChannels } from "../instrumentation/plugins/openai-codex-interceptors";
 import type {
   OpenAICodexClass,
@@ -28,8 +29,7 @@ export function wrapOpenAICodexSDK<T>(sdk: T): T {
   }
 
   if (!maybeSDK.Codex || typeof maybeSDK.Codex !== "function") {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported OpenAI Codex SDK. Not wrapping.");
+    debugLogger.notice.warn("Unsupported OpenAI Codex SDK. Not wrapping.");
     return sdk;
   }
 
diff --git a/js/src/wrappers/openrouter-agent.test.ts b/js/src/wrappers/openrouter-agent.test.ts
index 069960ca3..c84a48333 100644
--- a/js/src/wrappers/openrouter-agent.test.ts
+++ b/js/src/wrappers/openrouter-agent.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { afterEach, describe, expect, it, vi } from "vitest";
 import { wrapOpenRouterAgent } from "./openrouter-agent";
 import { openRouterAgentChannels } from "../instrumentation/plugins/openrouter-agent-interceptors";
@@ -8,7 +9,9 @@ describe("wrapOpenRouterAgent", () => {
   });
 
   it("returns the original value and warns for unsupported inputs", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const input = { notCallModel: true };
 
     expect(wrapOpenRouterAgent(input as object)).toBe(input);
diff --git a/js/src/wrappers/openrouter-agent.ts b/js/src/wrappers/openrouter-agent.ts
index 0df5ed972..dd077e704 100644
--- a/js/src/wrappers/openrouter-agent.ts
+++ b/js/src/wrappers/openrouter-agent.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { openRouterAgentChannels } from "../instrumentation/plugins/openrouter-agent-interceptors";
 import type {
   OpenRouterAgentCallModelRequest,
@@ -19,8 +20,9 @@ export function wrapOpenRouterAgent<T extends object>(agent: T): T {
     return openRouterAgentProxy(candidate as OpenRouterAgentClient) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported OpenRouter Agent library. Not wrapping.");
+  debugLogger.notice.warn(
+    "Unsupported OpenRouter Agent library. Not wrapping.",
+  );
   return agent;
 }
 
diff --git a/js/src/wrappers/openrouter.test.ts b/js/src/wrappers/openrouter.test.ts
index 4ee88ea24..50b0bdbb3 100644
--- a/js/src/wrappers/openrouter.test.ts
+++ b/js/src/wrappers/openrouter.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import {
   afterEach,
   beforeAll,
@@ -49,7 +50,9 @@ describe("openrouter wrapper", () => {
   });
 
   test("returns the original object for unsupported clients", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const invalid = { foo: "bar" };
 
     expect(wrapOpenRouter(invalid)).toBe(invalid);
diff --git a/js/src/wrappers/openrouter.ts b/js/src/wrappers/openrouter.ts
index 7bc2abd06..c3f6278be 100644
--- a/js/src/wrappers/openrouter.ts
+++ b/js/src/wrappers/openrouter.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { openRouterChannels } from "../instrumentation/plugins/openrouter-interceptors";
 import type {
   OpenRouterBeta,
@@ -43,8 +44,7 @@ export function wrapOpenRouter<T>(openrouter: T): T {
     return openRouterProxy(or as OpenRouterClient) as T;
   }
 
-  // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-  console.warn("Unsupported OpenRouter library. Not wrapping.");
+  debugLogger.notice.warn("Unsupported OpenRouter library. Not wrapping.");
   return openrouter;
 }
 
diff --git a/js/src/wrappers/pi-coding-agent.test.ts b/js/src/wrappers/pi-coding-agent.test.ts
index 7c6438fb1..678b6481c 100644
--- a/js/src/wrappers/pi-coding-agent.test.ts
+++ b/js/src/wrappers/pi-coding-agent.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { afterEach, describe, expect, it, vi } from "vitest";
 
 const { invoke } = vi.hoisted(() => ({
@@ -23,7 +24,9 @@ describe("wrapPiCodingAgentSDK", () => {
   });
 
   it("returns invalid modules unchanged", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const sdk = { Session: class {} };
 
     expect(wrapPiCodingAgentSDK(sdk)).toBe(sdk);
diff --git a/js/src/wrappers/pi-coding-agent.ts b/js/src/wrappers/pi-coding-agent.ts
index c922e7ed4..c7051b1b2 100644
--- a/js/src/wrappers/pi-coding-agent.ts
+++ b/js/src/wrappers/pi-coding-agent.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { piCodingAgentChannels } from "../instrumentation/plugins/pi-coding-agent-interceptors";
 import type {
   PiAgentSession,
@@ -19,8 +20,7 @@ export function wrapPiCodingAgentSDK<T>(sdk: T): T {
 
   const maybeSDK = sdk as Record<PropertyKey, unknown>;
   if (!maybeSDK.AgentSession || typeof maybeSDK.AgentSession !== "function") {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported Pi Coding Agent SDK. Not wrapping.");
+    debugLogger.notice.warn("Unsupported Pi Coding Agent SDK. Not wrapping.");
     return sdk;
   }
 
@@ -39,8 +39,7 @@ function patchAgentSessionClass(AgentSession: PiAgentSessionClass): void {
 
   const descriptor = Object.getOwnPropertyDescriptor(prototype, "prompt");
   if (!descriptor || typeof descriptor.value !== "function") {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported Pi Coding Agent SDK. Not wrapping.");
+    debugLogger.notice.warn("Unsupported Pi Coding Agent SDK. Not wrapping.");
     return;
   }
 
diff --git a/js/src/wrappers/shared/scorers.ts b/js/src/wrappers/shared/scorers.ts
index b3c11ee45..d627557e6 100644
--- a/js/src/wrappers/shared/scorers.ts
+++ b/js/src/wrappers/shared/scorers.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../debug-logger";
 import type { Span } from "../../logger";
 import type { Score } from "../../../util/score";
 import type { ScorerFunction } from "./types";
@@ -45,8 +46,7 @@ export async function runScorers(args: {
       } catch (scorerError) {
         // Log scorer error but don't fail the test — use metadata instead
         // of top-level error field to avoid marking the span as errored
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.warn("Braintrust: Scorer failed:", scorerError);
+        debugLogger.notice.warn("Scorer failed:", scorerError);
         const errorStr =
           scorerError instanceof Error
             ? `${scorerError.message}\n\n${scorerError.stack || ""}`
diff --git a/js/src/wrappers/strands-agent-sdk.test.ts b/js/src/wrappers/strands-agent-sdk.test.ts
index 5300ea3ae..82ab652ed 100644
--- a/js/src/wrappers/strands-agent-sdk.test.ts
+++ b/js/src/wrappers/strands-agent-sdk.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { afterEach, describe, expect, it, vi } from "vitest";
 
 const { invoke } = vi.hoisted(() => ({
@@ -23,7 +24,9 @@ describe("wrapStrandsAgentSDK", () => {
   });
 
   it("returns invalid modules unchanged", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const sdk = { AgentSession: class {} };
 
     expect(wrapStrandsAgentSDK(sdk)).toBe(sdk);
diff --git a/js/src/wrappers/strands-agent-sdk.ts b/js/src/wrappers/strands-agent-sdk.ts
index fe61102b5..90b6c28c4 100644
--- a/js/src/wrappers/strands-agent-sdk.ts
+++ b/js/src/wrappers/strands-agent-sdk.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { strandsAgentSDKChannels } from "../instrumentation/plugins/strands-agent-sdk-interceptors";
 import type {
   StrandsAgent,
@@ -35,8 +36,7 @@ export function wrapStrandsAgentSDK<T>(sdk: T): T {
     typeof maybeSDK.Graph !== "function" &&
     typeof maybeSDK.Swarm !== "function"
   ) {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported Strands Agent SDK. Not wrapping.");
+    debugLogger.notice.warn("Unsupported Strands Agent SDK. Not wrapping.");
     return sdk;
   }
 
diff --git a/js/src/wrappers/typesafe.test.ts b/js/src/wrappers/typesafe.test.ts
index 7aaa287d9..0d86402a5 100644
--- a/js/src/wrappers/typesafe.test.ts
+++ b/js/src/wrappers/typesafe.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import {
   afterEach,
   beforeAll,
@@ -112,7 +113,9 @@ describe("TypeSafe wrapper", () => {
   });
 
   it("returns unsupported clients unchanged", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const unsupported = { models: {} };
 
     expect(wrapTypeSafe(unsupported)).toBe(unsupported);
diff --git a/js/src/wrappers/typesafe.ts b/js/src/wrappers/typesafe.ts
index 9daafc704..3b639dd32 100644
--- a/js/src/wrappers/typesafe.ts
+++ b/js/src/wrappers/typesafe.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { typeSafeChannels } from "../instrumentation/plugins/typesafe-interceptors";
 import type {
   TypeSafeClient,
@@ -8,8 +9,7 @@ import type {
 export function wrapTypeSafe<T>(client: T): T;
 export function wrapTypeSafe(client: unknown): unknown {
   if (!isSupportedTypeSafeClient(client)) {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported TypeSafe AI library. Not wrapping.");
+    debugLogger.notice.warn("Unsupported TypeSafe AI library. Not wrapping.");
     return client;
   }
 
diff --git a/js/src/wrappers/vitest/index.ts b/js/src/wrappers/vitest/index.ts
index 6e2c24fdd..da2fdae12 100644
--- a/js/src/wrappers/vitest/index.ts
+++ b/js/src/wrappers/vitest/index.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../../debug-logger";
 import { wrapTest, wrapDescribe, getExperimentContext } from "./wrapper";
 import { wrapExpect } from "./expect-wrapper";
 import { summarizeAndFlush } from "../shared/flush";
@@ -98,9 +99,8 @@ export function wrapVitest<
     flushExperiment: async (options?: { displaySummary?: boolean }) => {
       const ctx = getExperimentContext();
       if (!ctx) {
-        // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-        console.warn(
-          "Braintrust: No experiment context found. Make sure you're using bt.describe() and calling flushExperiment() within an afterAll() hook.",
+        debugLogger.notice.warn(
+          "No experiment context found. Make sure you're using bt.describe() and calling flushExperiment() within an afterAll() hook.",
         );
         return;
       }
diff --git a/js/src/wrappers/voyageai.test.ts b/js/src/wrappers/voyageai.test.ts
index e9a1f9e19..323a0bc2f 100644
--- a/js/src/wrappers/voyageai.test.ts
+++ b/js/src/wrappers/voyageai.test.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import {
   afterEach,
   beforeAll,
@@ -40,7 +41,9 @@ describe("Voyage AI wrapper", () => {
   });
 
   it("returns unsupported clients unchanged", () => {
-    const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+    const warnSpy = vi
+      .spyOn(debugLogger.notice, "warn")
+      .mockImplementation(() => true);
     const unsupported = { tokenize: vi.fn() };
 
     expect(wrapVoyageAI(unsupported)).toBe(unsupported);
diff --git a/js/src/wrappers/voyageai.ts b/js/src/wrappers/voyageai.ts
index 22b04aada..b36e17a2b 100644
--- a/js/src/wrappers/voyageai.ts
+++ b/js/src/wrappers/voyageai.ts
@@ -1,3 +1,4 @@
+import { debugLogger } from "../debug-logger";
 import { voyageAIChannels } from "../instrumentation/plugins/voyageai-interceptors";
 import type {
   VoyageAIClient,
@@ -13,8 +14,7 @@ import type {
  */
 export function wrapVoyageAI<T>(client: T): T {
   if (!isSupportedVoyageAIClient(client)) {
-    // eslint-disable-next-line no-restricted-properties -- preserving intentional console usage.
-    console.warn("Unsupported Voyage AI library. Not wrapping.");
+    debugLogger.notice.warn("Unsupported Voyage AI library. Not wrapping.");
     return client;
   }