diff --git a/src/args.ts b/src/args.ts
index 0fe2f343..fd8d7221 100644
--- a/src/args.ts
+++ b/src/args.ts
@@ -1,5 +1,7 @@
 import type { GlobalFlags } from './types/flags';
 import type { OptionDef } from './command';
+import { CLIError } from './errors/base';
+import { ExitCode } from './errors/codes';
 
 /** Recognised spellings for an explicit boolean flag value, e.g. `--flag=false`. */
 const BOOLEAN_TRUE_VALUES = new Set(['true', '1', 'yes', 'on']);
@@ -117,6 +119,17 @@ export function parseFlags(argv: string[], options: OptionDef[]): GlobalFlags {
 
       const camelKey = kebabToCamel(key);
 
+      // Flags removed in newer versions — give users a clear pointer to the
+      // current way of doing the same thing instead of silently dropping
+      // their input.
+      if (key === 'base-url') {
+        throw new CLIError(
+          'Flag --base-url was removed.',
+          ExitCode.USAGE,
+          'Set base_url via `mmx config set --key base_url --value <url>`.',
+        );
+      }
+
       if (schema.booleans.has(camelKey)) {
         // A bare boolean flag (`--flag`) is true. Honour an explicit value
         // (`--flag=false`, `--flag=0`, ...) and reject an unrecognised one so a
diff --git a/src/command.ts b/src/command.ts
index 8d89da84..c1a3b85d 100644
--- a/src/command.ts
+++ b/src/command.ts
@@ -44,7 +44,6 @@ export function defineCommand(spec: CommandSpec): Command {
 export const GLOBAL_OPTIONS: OptionDef[] = [
   { flag: '--api-key <key>',     description: 'API key' },
   { flag: '--region <region>',   description: 'API region: global, cn' },
-  { flag: '--base-url <url>',    description: 'API base URL' },
   { flag: '--output <format>',   description: 'Output format: text, json' },
   { flag: '--timeout <seconds>', description: 'Request timeout', type: 'number' },
   { flag: '--quiet',             description: 'Suppress non-essential output' },
diff --git a/src/config/loader.ts b/src/config/loader.ts
index 77680441..e63fd6af 100644
--- a/src/config/loader.ts
+++ b/src/config/loader.ts
@@ -82,9 +82,8 @@ export function loadConfig(flags: GlobalFlags): Config {
   const needsRegionDetection = !explicitRegion
     && (!cachedRegion || (activeKey !== undefined && activeKey !== file.api_key));
 
-  const baseUrl = flags.baseUrl
-    || process.env.MINIMAX_BASE_URL
-    || file.base_url
+  // env/flag removed intentionally — see PR for context.
+  const baseUrl = file.base_url
     || file.oauth?.resource_url
     || REGIONS[region]
     || REGIONS.global;
diff --git a/src/errors/handler.ts b/src/errors/handler.ts
index 871e553c..dd2ae31b 100644
--- a/src/errors/handler.ts
+++ b/src/errors/handler.ts
@@ -35,7 +35,7 @@ export function handleError(err: unknown): never {
       return handleError(timeout);
     }
 
-    // Detect TypeError from fetch with invalid URL (e.g., malformed MINIMAX_BASE_URL)
+    // Detect TypeError from fetch with invalid URL (e.g., malformed base_url in config.json)
     if (err instanceof TypeError && err.message === "fetch failed") {
       const networkErr = new CLIError(
         "Network request failed.",
diff --git a/src/registry.ts b/src/registry.ts
index feca2332..2b302af8 100644
--- a/src/registry.ts
+++ b/src/registry.ts
@@ -218,8 +218,7 @@ ${b('Resources:')}
 
 ${b('Global Flags:')}
   ${a('--api-key <key>')}        ${d('API key (overrides all other auth)')}
-  ${a('--region <region>')}      ${d('API region: global (default), cn')}
-  ${a('--base-url <url>')}       ${d('API base URL (overrides region)')}
+  ${a('--region <region>')}      ${d('API region: global (default), cn)')}
   ${a('--output <format>')}      ${d('Output format: text, json')}
   ${a('--quiet')}                ${d('Suppress non-essential output')}
   ${a('--verbose')}              ${d('Print HTTP request/response details')}
diff --git a/src/types/flags.ts b/src/types/flags.ts
index 4f29f851..f7dbfbf6 100644
--- a/src/types/flags.ts
+++ b/src/types/flags.ts
@@ -1,6 +1,5 @@
 export interface GlobalFlags {
   apiKey?: string;
-  baseUrl?: string;
   output?: string;
   quiet: boolean;
   verbose: boolean;
diff --git a/test/args.test.ts b/test/args.test.ts
index e196d3e2..492b7c30 100644
--- a/test/args.test.ts
+++ b/test/args.test.ts
@@ -1,6 +1,8 @@
 import { describe, it, expect } from 'bun:test';
 import { parseFlags } from '../src/args';
 import type { OptionDef } from '../src/command';
+import { GLOBAL_OPTIONS } from '../src/command';
+import { CLIError } from '../src/errors/base';
 
 const OPTIONS: OptionDef[] = [
   { flag: '--timeout <seconds>', description: 'Request timeout', type: 'number' },
@@ -53,3 +55,29 @@ describe('parseFlags', () => {
     );
   });
 });
+
+describe('parseFlags — removed flags', () => {
+  it('rejects --base-url (space form) as a CLIError with a migration hint', () => {
+    let caught: unknown;
+    try {
+      parseFlags(['--base-url', 'https://api.example', 'search', 'query'], GLOBAL_OPTIONS);
+    } catch (err) {
+      caught = err;
+    }
+    expect(caught).toBeInstanceOf(CLIError);
+    expect((caught as CLIError).message).toBe('Flag --base-url was removed.');
+    expect((caught as CLIError).hint).toMatch(/mmx config set.*base_url/);
+  });
+
+  it('rejects --base-url=... (= form) as a CLIError', () => {
+    expect(() =>
+      parseFlags(['--base-url=https://api.example', 'search', 'query'], GLOBAL_OPTIONS),
+    ).toThrow(/--base-url was removed/);
+  });
+
+  it('still parses unrelated flags normally', () => {
+    const flags = parseFlags(['--region', 'cn', '--quiet'], GLOBAL_OPTIONS);
+    expect(flags.region).toBe('cn');
+    expect(flags.quiet).toBe(true);
+  });
+});
diff --git a/test/config/loader.test.ts b/test/config/loader.test.ts
index 1fcd8158..afc67c73 100644
--- a/test/config/loader.test.ts
+++ b/test/config/loader.test.ts
@@ -1,5 +1,5 @@
 import { describe, it, expect, beforeEach, afterEach, mock } from 'bun:test';
-import { copyFileSync, mkdirSync, readFileSync, rmSync, unlinkSync } from 'fs';
+import { copyFileSync, mkdirSync, readFileSync, rmSync, unlinkSync, writeFileSync } from 'fs';
 import { join } from 'path';
 import { tmpdir } from 'os';
 import { loadConfig, renameWithCrossDeviceFallback, writeConfigFile } from '../../src/config/loader';
@@ -156,3 +156,71 @@ describe('writeConfigFile', () => {
     expect(JSON.parse(readFileSync(configPath, 'utf-8')).output).toBe('json');
   });
 });
+
+describe('loadConfig — baseUrl source chain', () => {
+  const testDir = join(tmpdir(), `mmx-baseurl-test-${Date.now()}-${Math.random().toString(36).slice(2, 8)}`);
+  const configPath = join(testDir, 'config.json');
+  const originalConfigDir = process.env.MMX_CONFIG_DIR;
+
+  beforeEach(() => {
+    process.env.MMX_CONFIG_DIR = testDir;
+    delete process.env.MINIMAX_BASE_URL;
+    delete process.env.MINIMAX_REGION;
+  });
+
+  afterEach(() => {
+    if (originalConfigDir === undefined) delete process.env.MMX_CONFIG_DIR;
+    else process.env.MMX_CONFIG_DIR = originalConfigDir;
+    rmSync(testDir, { recursive: true, force: true });
+  });
+
+  function writeConfig(body: object): void {
+    mkdirSync(testDir, { recursive: true });
+    writeFileSync(configPath, JSON.stringify(body));
+  }
+
+  it('uses file.base_url when set, with no flag or env', () => {
+    writeConfig({ base_url: 'https://api.from-file.example' });
+    const cfg = loadConfig(baseFlags);
+    expect(cfg.baseUrl).toBe('https://api.from-file.example');
+  });
+
+  it('falls back to REGIONS.global when nothing is set', () => {
+    writeConfig({});
+    const cfg = loadConfig(baseFlags);
+    expect(cfg.baseUrl).toBe('https://api.minimax.io');
+  });
+
+  it('falls back to REGIONS[region] when region is set in config file', () => {
+    writeConfig({ region: 'cn' });
+    const cfg = loadConfig(baseFlags);
+    expect(cfg.baseUrl).toBe('https://api.minimaxi.com');
+  });
+
+  it('ignores MINIMAX_BASE_URL env even when file.base_url is missing', () => {
+    writeConfig({});
+    process.env.MINIMAX_BASE_URL = 'https://api.from-env.example';
+    const cfg = loadConfig(baseFlags);
+    expect(cfg.baseUrl).toBe('https://api.minimax.io');
+  });
+
+  it('file.base_url wins over MINIMAX_BASE_URL env', () => {
+    writeConfig({ base_url: 'https://api.from-file.example' });
+    process.env.MINIMAX_BASE_URL = 'https://api.from-env.example';
+    const cfg = loadConfig(baseFlags);
+    expect(cfg.baseUrl).toBe('https://api.from-file.example');
+  });
+
+  it('falls back to REGIONS[region] when region is set via env', () => {
+    writeConfig({});
+    process.env.MINIMAX_REGION = 'cn';
+    const cfg = loadConfig(baseFlags);
+    expect(cfg.baseUrl).toBe('https://api.minimaxi.com');
+  });
+
+  it('ignores malformed file.base_url (not starting with http) and falls back to regions', () => {
+    writeConfig({ base_url: 'not-a-url' });
+    const cfg = loadConfig(baseFlags);
+    expect(cfg.baseUrl).toBe('https://api.minimax.io');
+  });
+});