diff --git a/src/logger/runtime-logger.ts b/src/logger/runtime-logger.ts
index 1d695c2..2d93592 100644
--- a/src/logger/runtime-logger.ts
+++ b/src/logger/runtime-logger.ts
@@ -15,6 +15,13 @@ const LOG_LEVEL_PRIORITY: Record<RuntimeLogLevel, number> = {
   error: 3
 };
 
+function shouldLog(
+  level: RuntimeLogLevel,
+  minimumLevel: RuntimeLogLevel
+): boolean {
+  return LOG_LEVEL_PRIORITY[level] >= LOG_LEVEL_PRIORITY[minimumLevel];
+}
+
 export interface ConsoleRuntimeLoggerOptions {
   level?: RuntimeLogLevel;
   redactKeys?: RegExp;
@@ -135,6 +142,7 @@ export class InMemoryRuntimeLogger implements RuntimeLogger {
   private readonly redactKeys: RegExp;
 
   public constructor(options: InMemoryRuntimeLoggerOptions = {}) {
+    this.minimumLevel = options.level ?? "debug";
     this.maxEntries = options.maxEntries ?? 5_000;
     this.minimumLevel = options.level;
     this.redactKeys = options.redactKeys ?? DEFAULT_REDACT_KEYS;
diff --git a/tests/logger/console-runtime-logger-level.test.ts b/tests/logger/console-runtime-logger-level.test.ts
index 1797336..9de1db7 100644
--- a/tests/logger/console-runtime-logger-level.test.ts
+++ b/tests/logger/console-runtime-logger-level.test.ts
@@ -1,17 +1,26 @@
-import { describe, it, expect, vi, beforeEach } from "vitest";
-import { ConsoleRuntimeLogger } from "../../src/logger/runtime-logger.js";
+import { afterEach, describe, it, expect, vi, beforeEach } from "vitest";
+import {
+  ConsoleRuntimeLogger,
+  InMemoryRuntimeLogger
+} from "../../src/logger/runtime-logger.js";
 
 describe("ConsoleRuntimeLogger level filtering", () => {
   let infoSpy: ReturnType<typeof vi.spyOn>;
+  let debugSpy: ReturnType<typeof vi.spyOn>;
   let warnSpy: ReturnType<typeof vi.spyOn>;
   let errorSpy: ReturnType<typeof vi.spyOn>;
 
   beforeEach(() => {
     infoSpy = vi.spyOn(console, "info").mockImplementation(() => {});
+    debugSpy = vi.spyOn(console, "debug").mockImplementation(() => {});
     warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
     errorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
   });
 
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
   it("logs all levels when level=info (default)", () => {
     const logger = new ConsoleRuntimeLogger();
     logger.info("i");
@@ -41,4 +50,27 @@ describe("ConsoleRuntimeLogger level filtering", () => {
     expect(warnSpy).toHaveBeenCalledTimes(1);
     expect(errorSpy).toHaveBeenCalledTimes(1);
   });
+
+  it("matches in-memory filtering at the same configured threshold", () => {
+    const consoleLogger = new ConsoleRuntimeLogger({ level: "warn" });
+    const memoryLogger = new InMemoryRuntimeLogger({ level: "warn" });
+
+    consoleLogger.debug("debug");
+    consoleLogger.info("info");
+    consoleLogger.warn("warn");
+    consoleLogger.error("error");
+    memoryLogger.debug("debug");
+    memoryLogger.info("info");
+    memoryLogger.warn("warn");
+    memoryLogger.error("error");
+
+    expect(debugSpy).not.toHaveBeenCalled();
+    expect(infoSpy).not.toHaveBeenCalled();
+    expect(warnSpy).toHaveBeenCalledTimes(1);
+    expect(errorSpy).toHaveBeenCalledTimes(1);
+    expect(memoryLogger.entries.map((entry) => entry.level)).toEqual([
+      "warn",
+      "error"
+    ]);
+  });
 });
diff --git a/tests/logger/runtime-logger.test.ts b/tests/logger/runtime-logger.test.ts
index c42694b..2674806 100644
--- a/tests/logger/runtime-logger.test.ts
+++ b/tests/logger/runtime-logger.test.ts
@@ -5,6 +5,72 @@ import {
 } from "../../src/logger/runtime-logger.js";
 
 describe("InMemoryRuntimeLogger", () => {
+  it("records all supported levels by default", () => {
+    const logger = new InMemoryRuntimeLogger();
+
+    logger.debug("debug");
+    logger.info("info");
+    logger.warn("warn");
+    logger.error("error");
+
+    expect(logger.entries.map((entry) => entry.level)).toEqual([
+      "debug",
+      "info",
+      "warn",
+      "error"
+    ]);
+    expect(logger.size()).toBe(4);
+  });
+
+  it("filters entries below the configured threshold", () => {
+    const logger = new InMemoryRuntimeLogger({ level: "warn" });
+
+    logger.debug("debug");
+    logger.info("info");
+    logger.warn("warn");
+    logger.error("error");
+
+    expect(logger.entries.map((entry) => entry.level)).toEqual([
+      "warn",
+      "error"
+    ]);
+    expect(logger.size()).toBe(2);
+  });
+
+  it("preserves retained order and clear semantics after filtering", () => {
+    const logger = new InMemoryRuntimeLogger({ level: "warn" });
+
+    logger.info("ignored");
+    logger.warn("first");
+    logger.debug("also ignored");
+    logger.error("second");
+
+    expect(logger.entries.map((entry) => entry.message)).toEqual([
+      "first",
+      "second"
+    ]);
+    expect(logger.size()).toBe(2);
+
+    logger.clear();
+
+    expect(logger.entries).toEqual([]);
+    expect(logger.size()).toBe(0);
+  });
+
+  it("does not let filtered entries affect maxEntries eviction", () => {
+    const logger = new InMemoryRuntimeLogger({ level: "warn", maxEntries: 2 });
+
+    logger.warn("first");
+    logger.error("second");
+    logger.info("ignored");
+    logger.warn("third");
+
+    expect(logger.entries.map((entry) => entry.message)).toEqual([
+      "second",
+      "third"
+    ]);
+  });
+
   it("records info entries with correct level and message", () => {
     const logger = new InMemoryRuntimeLogger();
     logger.info("test message");