diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6004271cab9..1c4a8e6f205 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -86,6 +86,7 @@ Docs: https://docs.openclaw.ai
 - Cron/announce: preserve all deliverable text payloads for announce mode instead of collapsing to the last chunk, so multi-line cron reports deliver in full to Telegram forum topics.
 - Harden async approval followup delivery in webchat-only sessions (#57359) Thanks @joshavant.
 - Status: fix cache hit rate exceeding 100% by deriving denominator from prompt-side token fields instead of potentially undersized totalTokens. Fixes #26643.
+- Config/update: stop `openclaw doctor` write-backs from persisting plugin-injected channel defaults, so `openclaw update` no longer seeds config keys that later break service refresh validation. (#56834) Thanks @openperf.
 
 ## 2026.3.28
 
diff --git a/src/cli/update-cli/update-command.ts b/src/cli/update-cli/update-command.ts
index 58c63fd288b..7e641b03f30 100644
--- a/src/cli/update-cli/update-command.ts
+++ b/src/cli/update-cli/update-command.ts
@@ -638,12 +638,14 @@ async function maybeRestartService(params: {
             invocationCwd: params.invocationCwd,
           });
         } catch (err) {
-          if (!params.opts.json) {
-            defaultRuntime.log(
-              theme.warn(
-                `Failed to refresh gateway service environment from updated install: ${String(err)}`,
-              ),
-            );
+          // Always log the refresh failure so callers can detect it (issue #56772).
+          // Previously this was silently suppressed in --json mode, hiding the root
+          // cause and preventing auto-update callers from detecting the failure.
+          const message = `Failed to refresh gateway service environment from updated install: ${String(err)}`;
+          if (params.opts.json) {
+            defaultRuntime.error(message);
+          } else {
+            defaultRuntime.log(theme.warn(message));
           }
         }
       }
diff --git a/src/config/io.ts b/src/config/io.ts
index 65e8d064965..9d586c50e5f 100644
--- a/src/config/io.ts
+++ b/src/config/io.ts
@@ -31,6 +31,7 @@ import {
   resolveConfigIncludes,
 } from "./includes.js";
 import { migrateLegacyConfig } from "./legacy-migrate.js";
+import { normalizeLegacyWebSearchConfig } from "./legacy-web-search.js";
 import { findLegacyConfigIssues } from "./legacy.js";
 import {
   asResolvedSourceConfig,
@@ -2127,9 +2128,13 @@ export function createConfigIO(overrides: ConfigIoDeps = {}) {
     //
     // We use only the root file's parsed content (no $include resolution) to avoid
     // pulling values from included files into the root config on write-back.
-    // Apply env restoration to validated.config (which has runtime defaults stripped
-    // per issue #6070) rather than the raw caller input.
-    let cfgToWrite = validated.config;
+    // Use persistCandidate (the merge-patched value before validation) rather than
+    // validated.config, because plugin/channel AJV validation may inject schema
+    // defaults (e.g., enrichGroupParticipantsFromContacts) that should not be
+    // persisted to disk (issue #56772).
+    // Apply legacy web-search normalization so that migration results are still
+    // persisted even though we bypass validated.config.
+    let cfgToWrite = normalizeLegacyWebSearchConfig(persistCandidate) as OpenClawConfig;
     try {
       if (deps.fs.existsSync(configPath)) {
         const currentRaw = await deps.fs.promises.readFile(configPath, "utf-8");
diff --git a/src/config/io.write-config.test.ts b/src/config/io.write-config.test.ts
index f0f92f10c78..56d6de63078 100644
--- a/src/config/io.write-config.test.ts
+++ b/src/config/io.write-config.test.ts
@@ -5,6 +5,16 @@ import { afterAll, beforeAll, describe, expect, it, vi } from "vitest";
 import { createConfigIO } from "./io.js";
 import type { OpenClawConfig } from "./types.js";
 
+// Mock the plugin manifest registry so we can register a fake channel whose
+// AJV JSON Schema carries a `default` value.  This lets the #56772 regression
+// test exercise the exact code path that caused the bug: AJV injecting
+// defaults during the write-back validation pass.
+const mockLoadPluginManifestRegistry = vi.hoisted(() => vi.fn());
+
+vi.mock("../plugins/manifest-registry.js", () => ({
+  loadPluginManifestRegistry: (...args: unknown[]) => mockLoadPluginManifestRegistry(...args),
+}));
+
 describe("config io write", () => {
   let fixtureRoot = "";
   let homeCaseId = 0;
@@ -21,6 +31,13 @@ describe("config io write", () => {
 
   beforeAll(async () => {
     fixtureRoot = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-config-io-"));
+
+    // Default: return an empty plugin list so existing tests that don't need
+    // plugin-owned channel schemas keep working unchanged.
+    mockLoadPluginManifestRegistry.mockReturnValue({
+      diagnostics: [],
+      plugins: [],
+    });
   });
 
   afterAll(async () => {
@@ -353,6 +370,95 @@ describe("config io write", () => {
     });
   });
 
+  it("does not leak channel plugin AJV defaults into persisted config (issue #56772)", async () => {
+    // Regression test for #56772. Mock the BlueBubbles channel metadata so
+    // read-time AJV validation injects the same default that triggered the
+    // write-back leak.
+    mockLoadPluginManifestRegistry.mockReturnValue({
+      diagnostics: [],
+      plugins: [
+        {
+          id: "bluebubbles",
+          origin: "bundled",
+          channels: ["bluebubbles"],
+          channelCatalogMeta: {
+            id: "bluebubbles",
+            label: "BlueBubbles",
+            blurb: "BlueBubbles channel",
+          },
+          channelConfigs: {
+            bluebubbles: {
+              schema: {
+                type: "object",
+                properties: {
+                  enrichGroupParticipantsFromContacts: {
+                    type: "boolean",
+                    default: true,
+                  },
+                  serverUrl: {
+                    type: "string",
+                  },
+                },
+                additionalProperties: true,
+              },
+              uiHints: {},
+            },
+          },
+        },
+      ],
+    });
+
+    await withSuiteHome(async (home) => {
+      const { configPath, io, snapshot } = await writeConfigAndCreateIo({
+        home,
+        initialConfig: {
+          gateway: { port: 18789 },
+          channels: {
+            bluebubbles: {
+              serverUrl: "http://localhost:1234",
+            },
+          },
+        },
+      });
+
+      // Simulate doctor: clone snapshot.config, make a small change, write back.
+      const next = structuredClone(snapshot.config);
+      const gateway =
+        next.gateway && typeof next.gateway === "object"
+          ? (next.gateway as Record<string, unknown>)
+          : {};
+      next.gateway = {
+        ...gateway,
+        auth: { mode: "token" },
+      };
+      await io.writeConfigFile(next);
+
+      const persisted = JSON.parse(await fs.readFile(configPath, "utf-8")) as Record<
+        string,
+        unknown
+      >;
+
+      // The persisted config should contain only explicitly set values.
+      expect(persisted.gateway).toEqual({
+        port: 18789,
+        auth: { mode: "token" },
+      });
+
+      // The critical assertion: the AJV-injected BlueBubbles default must not
+      // appear in the persisted config.
+      const channels = persisted.channels as Record<string, Record<string, unknown>> | undefined;
+      expect(channels?.bluebubbles).toBeDefined();
+      expect(channels?.bluebubbles).not.toHaveProperty("enrichGroupParticipantsFromContacts");
+      expect(channels?.bluebubbles?.serverUrl).toBe("http://localhost:1234");
+    });
+
+    // Restore the default empty-plugins mock for subsequent tests.
+    mockLoadPluginManifestRegistry.mockReturnValue({
+      diagnostics: [],
+      plugins: [],
+    });
+  });
+
   it("does not reintroduce Slack/Discord legacy dm.policy defaults when writing", async () => {
     await withSuiteHome(async (home) => {
       const { configPath, io, snapshot } = await writeConfigAndCreateIo({
diff --git a/src/config/validation.channel-metadata.test.ts b/src/config/validation.channel-metadata.test.ts
index fae1d88b9fc..3961a35e4a7 100644
--- a/src/config/validation.channel-metadata.test.ts
+++ b/src/config/validation.channel-metadata.test.ts
@@ -6,42 +6,46 @@ vi.mock("../plugins/manifest-registry.js", () => ({
   loadPluginManifestRegistry: (...args: unknown[]) => mockLoadPluginManifestRegistry(...args),
 }));
 
-describe("validateConfigObjectRawWithPlugins channel metadata", () => {
-  it("applies bundled channel defaults from plugin-owned schema metadata", async () => {
-    mockLoadPluginManifestRegistry.mockReturnValue({
-      diagnostics: [],
-      plugins: [
-        {
+function setupTelegramSchemaWithDefault() {
+  mockLoadPluginManifestRegistry.mockReturnValue({
+    diagnostics: [],
+    plugins: [
+      {
+        id: "telegram",
+        origin: "bundled",
+        channels: ["telegram"],
+        channelCatalogMeta: {
           id: "telegram",
-          origin: "bundled",
-          channels: ["telegram"],
-          channelCatalogMeta: {
-            id: "telegram",
-            label: "Telegram",
-            blurb: "Telegram channel",
-          },
-          channelConfigs: {
-            telegram: {
-              schema: {
-                type: "object",
-                properties: {
-                  dmPolicy: {
-                    type: "string",
-                    enum: ["pairing", "allowlist"],
-                    default: "pairing",
-                  },
+          label: "Telegram",
+          blurb: "Telegram channel",
+        },
+        channelConfigs: {
+          telegram: {
+            schema: {
+              type: "object",
+              properties: {
+                dmPolicy: {
+                  type: "string",
+                  enum: ["pairing", "allowlist"],
+                  default: "pairing",
                 },
-                additionalProperties: false,
               },
-              uiHints: {},
+              additionalProperties: false,
             },
+            uiHints: {},
           },
         },
-      ],
-    });
+      },
+    ],
+  });
+}
 
-    const { validateConfigObjectRawWithPlugins } = await import("./validation.js");
-    const result = validateConfigObjectRawWithPlugins({
+describe("validateConfigObjectWithPlugins channel metadata (applyDefaults: true)", () => {
+  it("applies bundled channel defaults from plugin-owned schema metadata", async () => {
+    setupTelegramSchemaWithDefault();
+
+    const { validateConfigObjectWithPlugins } = await import("./validation.js");
+    const result = validateConfigObjectWithPlugins({
       channels: {
         telegram: {},
       },
@@ -55,3 +59,32 @@ describe("validateConfigObjectRawWithPlugins channel metadata", () => {
     }
   });
 });
+
+describe("validateConfigObjectRawWithPlugins channel metadata", () => {
+  it("still injects channel AJV defaults even in raw mode — persistence safety is handled by io.ts", async () => {
+    // Channel and plugin AJV validation always runs with applyDefaults: true
+    // (hardcoded) to avoid breaking schemas that mark defaulted fields as
+    // required (e.g., BlueBubbles enrichGroupParticipantsFromContacts).
+    //
+    // The actual protection against leaking these defaults to disk lives in
+    // writeConfigFile (io.ts), which uses persistCandidate (the pre-validation
+    // merge-patched value) instead of validated.config.
+    setupTelegramSchemaWithDefault();
+
+    const { validateConfigObjectRawWithPlugins } = await import("./validation.js");
+    const result = validateConfigObjectRawWithPlugins({
+      channels: {
+        telegram: {},
+      },
+    });
+
+    expect(result.ok).toBe(true);
+    if (result.ok) {
+      // AJV defaults ARE injected into validated.config even in raw mode.
+      // This is intentional — see comment above.
+      expect(result.config.channels?.telegram).toEqual(
+        expect.objectContaining({ dmPolicy: "pairing" }),
+      );
+    }
+  });
+});