diff --git a/packages/cli/src/ingest.test.ts b/packages/cli/src/ingest.test.ts
index 59df5e86..8f7bf5b8 100644
--- a/packages/cli/src/ingest.test.ts
+++ b/packages/cli/src/ingest.test.ts
@@ -14,6 +14,7 @@ import {
 import { initKtxProject, ktxLocalStateDbPath, loadKtxProject } from '@ktx/context/project';
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
 import { type KtxIngestArgs, runKtxIngest } from './ingest.js';
+import type { KtxCliLocalIngestAdaptersOptions } from './local-adapters.js';
 import {
   CliLookerSlWritingAgentRunner,
   CliMetabaseAgentRunner,
@@ -553,6 +554,46 @@ describe('runKtxIngest', () => {
     expect(io.stderr()).toBe('');
   });
 
+  it('keeps metabase JSON stdout free of operational adapter logs', async () => {
+    const projectDir = join(tempDir, 'project');
+    await writeMetabaseConfig(projectDir);
+    const io = makeIo();
+    let adapterOptions: KtxCliLocalIngestAdaptersOptions | undefined;
+
+    await expect(
+      runKtxIngest(
+        {
+          command: 'run',
+          projectDir,
+          connectionId: 'prod-metabase',
+          adapter: 'metabase',
+          outputMode: 'json',
+        },
+        io.io,
+        {
+          createAdapters: (_project, options) => {
+            adapterOptions = options;
+            options?.logger?.warn('adapter warning');
+            return [];
+          },
+          runLocalMetabaseIngest: async (input) => {
+            input.adapters.find((adapter) => adapter.source === 'metabase');
+            return {
+              metabaseConnectionId: 'prod-metabase',
+              status: 'all_succeeded',
+              totals: { workUnits: 0, failedWorkUnits: 0 },
+              children: [],
+            };
+          },
+        },
+      ),
+    ).resolves.toBe(0);
+
+    expect(adapterOptions?.logger).toEqual(expect.objectContaining({ warn: expect.any(Function) }));
+    expect(() => JSON.parse(io.stdout())).not.toThrow();
+    expect(io.stderr()).toBe('');
+  });
+
   it('rejects source-dir uploads through the metabase fan-out route', async () => {
     const projectDir = join(tempDir, 'project');
     await writeMetabaseConfig(projectDir);
@@ -764,17 +805,22 @@ describe('runKtxIngest', () => {
       ),
     ).resolves.toBe(0);
 
-    expect(createAdapters).toHaveBeenCalledWith(expect.objectContaining({ projectDir }), {
-      databaseIntrospectionUrl: 'http://127.0.0.1:8765',
-    });
+    expect(createAdapters).toHaveBeenCalledWith(
+      expect.objectContaining({ projectDir }),
+      expect.objectContaining({
+        databaseIntrospectionUrl: 'http://127.0.0.1:8765',
+        logger: expect.any(Object),
+      }),
+    );
     expect(runLocal).toHaveBeenCalledWith(
       expect.objectContaining({
         adapters: createdAdapters,
         adapter: 'fake',
         connectionId: 'warehouse',
-        pullConfigOptions: {
+        pullConfigOptions: expect.objectContaining({
           databaseIntrospectionUrl: 'http://127.0.0.1:8765',
-        },
+          logger: expect.any(Object),
+        }),
       }),
     );
   });
@@ -817,14 +863,19 @@ describe('runKtxIngest', () => {
       installPolicy: 'auto',
       io: io.io,
     };
-    expect(createAdapters).toHaveBeenCalledWith(expect.objectContaining({ projectDir }), {
-      managedDaemon: expectedManagedDaemon,
-    });
+    expect(createAdapters).toHaveBeenCalledWith(
+      expect.objectContaining({ projectDir }),
+      expect.objectContaining({
+        managedDaemon: expectedManagedDaemon,
+        logger: expect.any(Object),
+      }),
+    );
     expect(runLocal).toHaveBeenCalledWith(
       expect.objectContaining({
-        pullConfigOptions: {
+        pullConfigOptions: expect.objectContaining({
           managedDaemon: expectedManagedDaemon,
-        },
+          logger: expect.any(Object),
+        }),
       }),
     );
   });
@@ -878,9 +929,13 @@ describe('runKtxIngest', () => {
       ),
     ).resolves.toBe(0);
 
-    expect(createAdapters).toHaveBeenCalledWith(expect.objectContaining({ projectDir }), {
-      historicSqlConnectionId: 'warehouse',
-    });
+    expect(createAdapters).toHaveBeenCalledWith(
+      expect.objectContaining({ projectDir }),
+      expect.objectContaining({
+        historicSqlConnectionId: 'warehouse',
+        logger: expect.any(Object),
+      }),
+    );
     expect(runLocal).toHaveBeenCalledWith(
       expect.objectContaining({
         adapters: createdAdapters,
@@ -1119,15 +1174,19 @@ describe('runKtxIngest', () => {
       ),
     ).resolves.toBe(0);
 
-    expect(createAdapters).toHaveBeenCalledWith(expect.objectContaining({ projectDir }), {
-      looker: {
-        parser: pullConfigOptions.looker.parser,
-      },
-    });
+    expect(createAdapters).toHaveBeenCalledWith(
+      expect.objectContaining({ projectDir }),
+      expect.objectContaining({
+        logger: expect.any(Object),
+        looker: {
+          parser: pullConfigOptions.looker.parser,
+        },
+      }),
+    );
     expect(runLocal).toHaveBeenCalledWith(
       expect.objectContaining({
         agentRunner,
-        pullConfigOptions,
+        pullConfigOptions: expect.objectContaining(pullConfigOptions),
       }),
     );
   });
diff --git a/packages/cli/src/ingest.ts b/packages/cli/src/ingest.ts
index 39bf21bb..516d4dd6 100644
--- a/packages/cli/src/ingest.ts
+++ b/packages/cli/src/ingest.ts
@@ -18,6 +18,7 @@ import {
 } from '@ktx/context/ingest';
 import { loadKtxProject } from '@ktx/context/project';
 import { readIngestReportSnapshotFile } from './ingest-report-file.js';
+import { createCliOperationalLogger } from './io/logger.js';
 import { createKtxCliLocalIngestAdapters } from './local-adapters.js';
 import type { KtxManagedPythonInstallPolicy } from './managed-python-command.js';
 import { type KtxMemoryFlowStdin, renderMemoryFlowInteractively } from './memory-flow-interactive.js';
@@ -475,11 +476,13 @@ export async function runKtxIngest(
       const executeLocalIngest = deps.runLocalIngest ?? runLocalIngest;
       const localIngestOptions = deps.localIngestOptions ?? {};
       const managedDaemon = managedDaemonOptionsForIngestRun(args, io);
+      const operationalLogger = createCliOperationalLogger(io, args.outputMode);
       const adapterOptions = {
         ...(localIngestOptions.pullConfigOptions ?? {}),
         ...(args.databaseIntrospectionUrl ? { databaseIntrospectionUrl: args.databaseIntrospectionUrl } : {}),
         ...(managedDaemon ? { managedDaemon } : {}),
         ...(args.adapter === 'historic-sql' ? { historicSqlConnectionId: args.connectionId } : {}),
+        logger: operationalLogger,
       };
       if (args.adapter === 'metabase' && args.sourceDir) {
         throw new Error('source-dir uploads are not supported for the Metabase fan-out adapter');
diff --git a/packages/cli/src/io/logger.test.ts b/packages/cli/src/io/logger.test.ts
new file mode 100644
index 00000000..bf21a150
--- /dev/null
+++ b/packages/cli/src/io/logger.test.ts
@@ -0,0 +1,65 @@
+import { describe, expect, it, vi } from 'vitest';
+import { createCliOperationalLogger, createNoopOperationalLogger } from './logger.js';
+
+function makeIo() {
+  let stdout = '';
+  let stderr = '';
+  return {
+    io: {
+      stdout: {
+        write: (chunk: string) => {
+          stdout += chunk;
+        },
+      },
+      stderr: {
+        write: (chunk: string) => {
+          stderr += chunk;
+        },
+      },
+    },
+    stdout: () => stdout,
+    stderr: () => stderr,
+  };
+}
+
+describe('createCliOperationalLogger', () => {
+  it('routes operational messages to stderr outside JSON mode', () => {
+    const io = makeIo();
+    const logger = createCliOperationalLogger(io.io, 'plain');
+
+    logger.log('progress');
+    logger.warn('warning');
+    logger.error('failure');
+    logger.debug?.('debug');
+
+    expect(io.stdout()).toBe('');
+    expect(io.stderr()).toBe('progress\nwarning\nfailure\ndebug\n');
+  });
+
+  it('suppresses operational messages in JSON mode by default', () => {
+    const io = makeIo();
+    const logger = createCliOperationalLogger(io.io, 'json');
+
+    logger.log('progress');
+    logger.warn('warning');
+    logger.error('failure');
+    logger.debug?.('debug');
+
+    expect(io.stdout()).toBe('');
+    expect(io.stderr()).toBe('');
+  });
+});
+
+describe('createNoopOperationalLogger', () => {
+  it('never writes', () => {
+    const logger = createNoopOperationalLogger();
+    const warn = vi.spyOn(console, 'warn').mockImplementation(() => undefined);
+
+    logger.log('progress');
+    logger.warn('warning');
+    logger.error('failure');
+    logger.debug?.('debug');
+
+    expect(warn).not.toHaveBeenCalled();
+  });
+});
diff --git a/packages/cli/src/io/logger.ts b/packages/cli/src/io/logger.ts
new file mode 100644
index 00000000..e9952254
--- /dev/null
+++ b/packages/cli/src/io/logger.ts
@@ -0,0 +1,40 @@
+import type { KtxCliIo } from '../cli-runtime.js';
+import type { KtxOutputMode } from './mode.js';
+
+export interface KtxOperationalLogger {
+  log(message: string): void;
+  warn(message: string): void;
+  error(message: string): void;
+  debug?(message: string): void;
+}
+
+export type KtxOperationalOutputMode = KtxOutputMode | 'viz';
+
+function writeLine(io: KtxCliIo, message: string): void {
+  io.stderr.write(message.endsWith('\n') ? message : `${message}\n`);
+}
+
+export function createNoopOperationalLogger(): KtxOperationalLogger {
+  return {
+    log: () => undefined,
+    warn: () => undefined,
+    error: () => undefined,
+    debug: () => undefined,
+  };
+}
+
+export function createCliOperationalLogger(
+  io: KtxCliIo,
+  mode: KtxOperationalOutputMode,
+): KtxOperationalLogger {
+  if (mode === 'json') {
+    return createNoopOperationalLogger();
+  }
+
+  return {
+    log: (message) => writeLine(io, message),
+    warn: (message) => writeLine(io, message),
+    error: (message) => writeLine(io, message),
+    debug: (message) => writeLine(io, message),
+  };
+}
diff --git a/packages/cli/src/local-adapters.ts b/packages/cli/src/local-adapters.ts
index d0a5f571..8557674c 100644
--- a/packages/cli/src/local-adapters.ts
+++ b/packages/cli/src/local-adapters.ts
@@ -35,6 +35,7 @@ import {
   managedDaemonDatabaseIntrospectionOptions,
   type ManagedPythonCoreDaemonOptions,
 } from './managed-python-http.js';
+import type { KtxOperationalLogger } from './io/logger.js';
 
 function hasSnowflakeDriver(connection: unknown): boolean {
   return (
@@ -162,6 +163,7 @@ export interface KtxCliLocalIngestAdaptersOptions extends DefaultLocalIngestAdap
   sqlAnalysis?: SqlAnalysisPort;
   sqlAnalysisUrl?: string;
   managedDaemon?: ManagedPythonCoreDaemonOptions;
+  logger?: KtxOperationalLogger;
 }
 
 function historicSqlRecord(connection: unknown): Record<string, unknown> | null {
diff --git a/packages/context/src/ingest/adapters/looker/local-looker.adapter.ts b/packages/context/src/ingest/adapters/looker/local-looker.adapter.ts
index c1869da9..a29fecd1 100644
--- a/packages/context/src/ingest/adapters/looker/local-looker.adapter.ts
+++ b/packages/context/src/ingest/adapters/looker/local-looker.adapter.ts
@@ -1,4 +1,5 @@
 import type { KtxLocalProject, KtxProjectConnectionConfig } from '../../../project/index.js';
+import type { LookerClientLogger } from './client.js';
 import {
   DefaultLookerClientFactory,
   DefaultLookerConnectionClientFactory,
@@ -59,8 +60,11 @@ export function createLocalLookerCredentialResolver(
 export function createLocalLookerSourceAdapter(
   project: KtxLocalProject,
   env: NodeJS.ProcessEnv = process.env,
+  logger?: LookerClientLogger,
 ): LookerSourceAdapter {
-  const connectionFactory = new DefaultLookerConnectionClientFactory(createLocalLookerCredentialResolver(project, env));
+  const connectionFactory = new DefaultLookerConnectionClientFactory(createLocalLookerCredentialResolver(project, env), {
+    ...(logger ? { logger } : {}),
+  });
   return new LookerSourceAdapter({
     clientFactory: new DefaultLookerClientFactory(connectionFactory),
   });
diff --git a/packages/context/src/ingest/adapters/metabase/local-metabase.adapter.ts b/packages/context/src/ingest/adapters/metabase/local-metabase.adapter.ts
index bd81413f..ec5e163e 100644
--- a/packages/context/src/ingest/adapters/metabase/local-metabase.adapter.ts
+++ b/packages/context/src/ingest/adapters/metabase/local-metabase.adapter.ts
@@ -1,12 +1,17 @@
 import type { KtxLocalProject, KtxProjectConnectionConfig } from '../../../project/index.js';
 import { ktxLocalStateDbPath } from '../../../project/index.js';
 import { resolveKtxConfigReference } from '../../../core/config-reference.js';
-import { DEFAULT_METABASE_CLIENT_CONFIG, DefaultMetabaseConnectionClientFactory } from './client.js';
+import {
+  DEFAULT_METABASE_CLIENT_CONFIG,
+  DefaultMetabaseConnectionClientFactory,
+  type MetabaseClientLogger,
+} from './client.js';
 import {
   IngestMetabaseClientFactory,
   type MetabaseClientConfig,
   type MetabaseClientRuntimeConfig,
 } from './client-port.js';
+import type { MetabaseFetchLogger } from './fetch.js';
 import { LocalMetabaseSourceStateReader } from './local-source-state-store.js';
 import { MetabaseSourceAdapter } from './metabase.adapter.js';
 
@@ -50,6 +55,7 @@ export function metabaseRuntimeConfigFromLocalConnection(
 interface CreateLocalMetabaseSourceAdapterOptions {
   env?: NodeJS.ProcessEnv;
   defaultClientConfig?: MetabaseClientConfig;
+  logger?: MetabaseClientLogger & MetabaseFetchLogger;
 }
 
 export function createLocalMetabaseSourceAdapter(
@@ -65,9 +71,11 @@ export function createLocalMetabaseSourceAdapter(
         options.env,
       ),
     options.defaultClientConfig ?? DEFAULT_METABASE_CLIENT_CONFIG,
+    options.logger,
   );
   return new MetabaseSourceAdapter({
     clientFactory: new IngestMetabaseClientFactory(connectionFactory),
     sourceStateReader,
+    ...(options.logger ? { logger: options.logger } : {}),
   });
 }
diff --git a/packages/context/src/ingest/adapters/metabase/metabase.adapter.ts b/packages/context/src/ingest/adapters/metabase/metabase.adapter.ts
index 1c0bb53b..cff59641 100644
--- a/packages/context/src/ingest/adapters/metabase/metabase.adapter.ts
+++ b/packages/context/src/ingest/adapters/metabase/metabase.adapter.ts
@@ -4,7 +4,7 @@ import type { ChunkResult, DiffSet, FetchContext, ScopeDescriptor, SourceAdapter
 import { chunkMetabaseStagedDir } from './chunk.js';
 import type { MetabaseClientFactory } from './client-port.js';
 import { detectMetabaseStagedDir } from './detect.js';
-import { fetchMetabaseBundle } from './fetch.js';
+import { fetchMetabaseBundle, type MetabaseFetchLogger } from './fetch.js';
 import { computeFetchScope, hashScope, isPathInMetabaseScope } from './fetch-scope.js';
 import type { MetabaseSourceStateReader } from './source-state-port.js';
 import { STAGED_FILES, stagedSyncConfigSchema } from './types.js';
@@ -12,6 +12,7 @@ import { STAGED_FILES, stagedSyncConfigSchema } from './types.js';
 export interface MetabaseSourceAdapterDeps {
   clientFactory: MetabaseClientFactory;
   sourceStateReader: MetabaseSourceStateReader;
+  logger?: MetabaseFetchLogger;
 }
 
 export class MetabaseSourceAdapter implements SourceAdapter {
@@ -31,6 +32,7 @@ export class MetabaseSourceAdapter implements SourceAdapter {
       ctx,
       clientFactory: this.deps.clientFactory,
       sourceStateReader: this.deps.sourceStateReader,
+      ...(this.deps.logger ? { logger: this.deps.logger } : {}),
     });
   }
 
diff --git a/packages/context/src/ingest/adapters/notion/notion.adapter.ts b/packages/context/src/ingest/adapters/notion/notion.adapter.ts
index 896ef69f..fba68cee 100644
--- a/packages/context/src/ingest/adapters/notion/notion.adapter.ts
+++ b/packages/context/src/ingest/adapters/notion/notion.adapter.ts
@@ -14,7 +14,7 @@ import type {
 import { chunkNotionStagedDir, describeNotionScope } from './chunk.js';
 import { clusterNotionWorkUnits } from './cluster.js';
 import { detectNotionStagedDir } from './detect.js';
-import { fetchNotionSnapshot } from './fetch.js';
+import { fetchNotionSnapshot, type NotionFetchLogger } from './fetch.js';
 import { NotionClient } from './notion-client.js';
 import { parseNotionPullConfig } from './pull-config.js';
 import { type NotionMetadata, notionManifestSchema, notionMetadataSchema } from './types.js';
@@ -31,6 +31,7 @@ interface NotionPullSucceededContext {
 
 export interface NotionSourceAdapterDeps {
   onPullSucceeded?: (ctx: NotionPullSucceededContext) => Promise<void>;
+  logger?: NotionFetchLogger;
 }
 
 export class NotionSourceAdapter implements SourceAdapter {
@@ -48,7 +49,12 @@ export class NotionSourceAdapter implements SourceAdapter {
 
   async fetch(pullConfig: unknown, stagedDir: string, _ctx: FetchContext): Promise<void> {
     const config = parseNotionPullConfig(pullConfig);
-    await fetchNotionSnapshot({ client: new NotionClient(config.authToken), config, stagedDir });
+    await fetchNotionSnapshot({
+      client: new NotionClient(config.authToken),
+      config,
+      stagedDir,
+      ...(this.deps.logger ? { logger: this.deps.logger } : {}),
+    });
   }
 
   chunk(stagedDir: string, diffSet?: DiffSet): Promise<ChunkResult> {
diff --git a/packages/context/src/ingest/local-adapters.ts b/packages/context/src/ingest/local-adapters.ts
index 93d6b063..dc4f50a4 100644
--- a/packages/context/src/ingest/local-adapters.ts
+++ b/packages/context/src/ingest/local-adapters.ts
@@ -19,6 +19,7 @@ import {
 } from './adapters/live-database/daemon-introspection.js';
 import { LiveDatabaseSourceAdapter } from './adapters/live-database/live-database.adapter.js';
 import { createDaemonLookerTableIdentifierParser } from './adapters/looker/daemon-table-identifier-parser.js';
+import type { LookerClientLogger } from './adapters/looker/client.js';
 import { DefaultLookerConnectionClientFactory } from './adapters/looker/factory.js';
 import { createLocalLookerCredentialResolver } from './adapters/looker/local-looker.adapter.js';
 import { LocalLookerRuntimeStore } from './adapters/looker/local-runtime-store.js';
@@ -32,9 +33,12 @@ import type { LookerRuntimeClient } from './adapters/looker/fetch.js';
 import { LookmlSourceAdapter } from './adapters/lookml/lookml.adapter.js';
 import { pullConfigFromIntegrationConfig } from './adapters/lookml/pull-config.js';
 import { createLocalMetabaseSourceAdapter } from './adapters/metabase/local-metabase.adapter.js';
+import type { MetabaseClientLogger } from './adapters/metabase/client.js';
+import type { MetabaseFetchLogger } from './adapters/metabase/fetch.js';
 import { MetricflowSourceAdapter } from './adapters/metricflow/metricflow.adapter.js';
 import { pullConfigFromMetricflowIntegration } from './adapters/metricflow/pull-config.js';
 import { NotionSourceAdapter } from './adapters/notion/notion.adapter.js';
+import type { NotionFetchLogger } from './adapters/notion/fetch.js';
 import { seedLocalMappingStateFromKtxYaml } from './local-mapping-reconcile.js';
 import type { SourceAdapter } from './types.js';
 
@@ -56,14 +60,23 @@ export interface DefaultLocalIngestAdaptersOptions {
     parser?: LookerTableIdentifierParser;
     env?: NodeJS.ProcessEnv;
   };
+  logger?: LocalIngestOperationalLogger;
 }
 
+type LocalIngestOperationalLogger = MetabaseClientLogger &
+  MetabaseFetchLogger &
+  LookerClientLogger &
+  NotionFetchLogger;
+
 export function createDefaultLocalIngestAdapters(
   project: KtxLocalProject,
   options: DefaultLocalIngestAdaptersOptions = {},
 ): SourceAdapter[] {
   const lookerConnectionFactory = new DefaultLookerConnectionClientFactory(
     createLocalLookerCredentialResolver(project, options.looker?.env),
+    {
+      ...(options.logger ? { logger: options.logger } : {}),
+    },
   );
 
   const adapters: SourceAdapter[] = [
@@ -77,7 +90,9 @@ export function createDefaultLocalIngestAdapters(
     }),
     new LookmlSourceAdapter({ homeDir: join(project.projectDir, '.ktx/cache') }),
     new DbtSourceAdapter({ homeDir: join(project.projectDir, '.ktx/cache') }),
-    createLocalMetabaseSourceAdapter(project),
+    createLocalMetabaseSourceAdapter(project, {
+      ...(options.logger ? { logger: options.logger } : {}),
+    }),
     new LookerSourceAdapter({
       clientFactory: {
         async createClient(config, ctx) {
@@ -89,7 +104,9 @@ export function createDefaultLocalIngestAdapters(
       },
     }),
     new MetricflowSourceAdapter({ homeDir: join(project.projectDir, '.ktx/cache') }),
-    new NotionSourceAdapter(),
+    new NotionSourceAdapter({
+      ...(options.logger ? { logger: options.logger } : {}),
+    }),
   ];
 
   if (options.historicSql) {