diff --git a/src/cli/doctor/checks/index.ts b/src/cli/doctor/checks/index.ts
index 55e908b32..428deb4ec 100644
--- a/src/cli/doctor/checks/index.ts
+++ b/src/cli/doctor/checks/index.ts
@@ -5,6 +5,7 @@ import { checkConfig } from "./config"
 import { checkTools, gatherToolsSummary } from "./tools"
 import { checkModels } from "./model-resolution"
 import { checkTeamMode } from "./team-mode"
+import { checkTuiPluginConfig } from "./tui-plugin-config"
 
 export type { CheckDefinition }
 export * from "./model-resolution-types"
@@ -23,6 +24,11 @@ export function getAllCheckDefinitions(): CheckDefinition[] {
       name: CHECK_NAMES[CHECK_IDS.CONFIG],
       check: checkConfig,
     },
+    {
+      id: CHECK_IDS.TUI_PLUGIN,
+      name: CHECK_NAMES[CHECK_IDS.TUI_PLUGIN],
+      check: checkTuiPluginConfig,
+    },
     {
       id: CHECK_IDS.TOOLS,
       name: CHECK_NAMES[CHECK_IDS.TOOLS],
diff --git a/src/cli/doctor/checks/tui-plugin-config.test.ts b/src/cli/doctor/checks/tui-plugin-config.test.ts
new file mode 100644
index 000000000..86f47def5
--- /dev/null
+++ b/src/cli/doctor/checks/tui-plugin-config.test.ts
@@ -0,0 +1,159 @@
+import { afterEach, beforeEach, describe, expect, it } from "bun:test"
+import { mkdirSync, rmSync, writeFileSync } from "node:fs"
+import { tmpdir } from "node:os"
+import { join } from "node:path"
+
+import { PLUGIN_NAME } from "../../../shared"
+import { checkTuiPluginConfig } from "./tui-plugin-config"
+
+let testConfigDir: string
+let originalConfigDir: string | undefined
+
+function writeOpenCodeConfig(plugins: string[]): void {
+  writeFileSync(
+    join(testConfigDir, "opencode.json"),
+    JSON.stringify({ plugin: plugins }, null, 2) + "\n",
+    "utf-8",
+  )
+}
+
+function writeTuiConfig(plugins: string[]): void {
+  writeFileSync(
+    join(testConfigDir, "tui.json"),
+    JSON.stringify({ plugin: plugins }, null, 2) + "\n",
+    "utf-8",
+  )
+}
+
+function writeFilePluginPackage(dir: string, packageName: string): string {
+  mkdirSync(dir, { recursive: true })
+  writeFileSync(
+    join(dir, "package.json"),
+    JSON.stringify({ name: packageName }, null, 2) + "\n",
+    "utf-8",
+  )
+  return `file:${dir}`
+}
+
+describe("tui-plugin-config check", () => {
+  beforeEach(() => {
+    originalConfigDir = process.env.OPENCODE_CONFIG_DIR
+    testConfigDir = join(
+      tmpdir(),
+      `omo-doctor-tui-${Date.now()}-${Math.random().toString(36).slice(2)}`,
+    )
+    mkdirSync(testConfigDir, { recursive: true })
+    process.env.OPENCODE_CONFIG_DIR = testConfigDir
+  })
+
+  afterEach(() => {
+    rmSync(testConfigDir, { recursive: true, force: true })
+    if (originalConfigDir === undefined) {
+      delete process.env.OPENCODE_CONFIG_DIR
+    } else {
+      process.env.OPENCODE_CONFIG_DIR = originalConfigDir
+    }
+  })
+
+  it("passes when both server and TUI entries are registered", async () => {
+    //#given opencode.json has the server entry and tui.json has the TUI entry
+    writeOpenCodeConfig([PLUGIN_NAME])
+    writeTuiConfig([`${PLUGIN_NAME}/tui`])
+
+    //#when running the check
+    const result = await checkTuiPluginConfig()
+
+    //#then both are detected and status is pass
+    expect(result.status).toBe("pass")
+    expect(result.issues).toHaveLength(0)
+    expect(result.name).toBe("TUI Plugin")
+  })
+
+  it("warns when server is registered but TUI entry is missing", async () => {
+    //#given opencode.json has the server entry but tui.json does not
+    writeOpenCodeConfig([PLUGIN_NAME])
+    writeTuiConfig(["some-other-tui-plugin"])
+
+    //#when running the check
+    const result = await checkTuiPluginConfig()
+
+    //#then status is warn with a single warning issue
+    expect(result.status).toBe("warn")
+    expect(result.issues).toHaveLength(1)
+    expect(result.issues[0].severity).toBe("warning")
+    expect(result.issues[0].title).toContain("TUI plugin entry missing")
+    expect(result.issues[0].fix).toBeDefined()
+  })
+
+  it("warns when server is registered but tui.json does not exist", async () => {
+    //#given opencode.json has the server entry and tui.json is absent
+    writeOpenCodeConfig([PLUGIN_NAME])
+
+    //#when running the check
+    const result = await checkTuiPluginConfig()
+
+    //#then status is warn — missing file means missing entry
+    expect(result.status).toBe("warn")
+    expect(result.issues).toHaveLength(1)
+    expect(result.issues[0].severity).toBe("warning")
+  })
+
+  it("passes when tui.json has a file: entry pointing at our package", async () => {
+    //#given opencode.json has the server entry and tui.json uses a file: URL
+    //#       pointing at a local checkout of our package
+    writeOpenCodeConfig([PLUGIN_NAME])
+    const localPkgDir = join(testConfigDir, "local-checkout")
+    const fileEntry = writeFilePluginPackage(localPkgDir, "oh-my-opencode")
+    writeTuiConfig([fileEntry])
+
+    //#when running the check
+    const result = await checkTuiPluginConfig()
+
+    //#then file: entry satisfies registration and status is pass
+    expect(result.status).toBe("pass")
+    expect(result.issues).toHaveLength(0)
+  })
+
+  it("warns when tui.json has our entry but server plugin is missing from opencode.json", async () => {
+    //#given tui.json has the TUI entry but opencode.json does not have the server entry
+    writeOpenCodeConfig(["some-other-plugin"])
+    writeTuiConfig([`${PLUGIN_NAME}/tui`])
+
+    //#when running the check
+    const result = await checkTuiPluginConfig()
+
+    //#then status is warn — TUI-only registration can't function without the server side
+    expect(result.status).toBe("warn")
+    expect(result.issues).toHaveLength(1)
+    expect(result.issues[0].severity).toBe("warning")
+    expect(result.issues[0].title).toContain("Server plugin entry missing")
+    expect(result.issues[0].fix).toBeDefined()
+  })
+
+  it("skips when neither config registers the plugin", async () => {
+    //#given an opencode.json and tui.json with no oh-my-openagent entries
+    writeOpenCodeConfig(["some-other-plugin"])
+    writeTuiConfig(["some-other-tui-plugin"])
+
+    //#when running the check
+    const result = await checkTuiPluginConfig()
+
+    //#then status is skip — plugin not installed at all
+    expect(result.status).toBe("skip")
+    expect(result.issues).toHaveLength(0)
+    expect(result.message).toContain("not registered")
+  })
+
+  it("passes when legacy server entry is paired with legacy TUI entry", async () => {
+    //#given legacy package names in both configs
+    writeOpenCodeConfig(["oh-my-opencode"])
+    writeTuiConfig(["oh-my-opencode/tui"])
+
+    //#when running the check
+    const result = await checkTuiPluginConfig()
+
+    //#then legacy aliases are accepted
+    expect(result.status).toBe("pass")
+    expect(result.issues).toHaveLength(0)
+  })
+})
diff --git a/src/cli/doctor/checks/tui-plugin-config.ts b/src/cli/doctor/checks/tui-plugin-config.ts
new file mode 100644
index 000000000..8fe07024e
--- /dev/null
+++ b/src/cli/doctor/checks/tui-plugin-config.ts
@@ -0,0 +1,181 @@
+import { existsSync, readFileSync } from "node:fs"
+import { join } from "node:path"
+
+import {
+  ACCEPTED_PACKAGE_NAMES,
+  LEGACY_PLUGIN_NAME,
+  PLUGIN_NAME,
+  getOpenCodeConfigDir,
+  getOpenCodeConfigPaths,
+  parseJsonc,
+} from "../../../shared"
+import { CHECK_IDS, CHECK_NAMES } from "../constants"
+import type { CheckResult, DoctorIssue } from "../types"
+
+const TUI_SUBPATH = "tui"
+
+interface OpenCodeConfigShape {
+  plugin?: string[]
+}
+
+interface TuiConfigShape {
+  plugin?: string[]
+}
+
+interface ServerPluginInfo {
+  registered: boolean
+  configPath: string | null
+}
+
+interface TuiPluginInfo {
+  registered: boolean
+  configPath: string | null
+  exists: boolean
+}
+
+// Returns true if `entry` is a file:-URL pointing at a directory whose
+// package.json declares one of our accepted package names. opencode-tui loads
+// such entries via the `./tui` subpath export, so a `file:` entry already
+// satisfies the TUI plugin registration even without an explicit
+// `oh-my-openagent/tui` entry. Mirrors the helper used in
+// add-tui-plugin-to-tui-config.ts during installation.
+function isOurFilePluginEntry(entry: string): boolean {
+  if (!entry.startsWith("file:")) return false
+  let path = entry.slice("file:".length)
+  if (path.startsWith("//")) path = path.slice(2)
+  try {
+    const pkgJsonPath = join(path, "package.json")
+    if (!existsSync(pkgJsonPath)) return false
+    const parsed = JSON.parse(readFileSync(pkgJsonPath, "utf-8")) as { name?: unknown }
+    return typeof parsed.name === "string"
+      && (ACCEPTED_PACKAGE_NAMES as readonly string[]).includes(parsed.name)
+  } catch {
+    return false
+  }
+}
+
+function isServerPluginEntry(entry: string): boolean {
+  if (entry === PLUGIN_NAME || entry.startsWith(`${PLUGIN_NAME}@`)) return true
+  if (entry === LEGACY_PLUGIN_NAME || entry.startsWith(`${LEGACY_PLUGIN_NAME}@`)) return true
+  if (entry.startsWith("file:") && isOurFilePluginEntry(entry)) return true
+  return false
+}
+
+function isTuiPluginEntry(entry: string): boolean {
+  const canonicalPrefix = `${PLUGIN_NAME}/${TUI_SUBPATH}`
+  const legacyPrefix = `${LEGACY_PLUGIN_NAME}/${TUI_SUBPATH}`
+  if (entry === canonicalPrefix || entry.startsWith(`${canonicalPrefix}@`)) return true
+  if (entry === legacyPrefix || entry.startsWith(`${legacyPrefix}@`)) return true
+  // file: entries pointing at our package already expose the ./tui subpath via
+  // package.json `exports`, so the TUI plugin loads without a separate entry.
+  if (entry.startsWith("file:") && isOurFilePluginEntry(entry)) return true
+  return false
+}
+
+export function detectServerPluginRegistration(): ServerPluginInfo {
+  const paths = getOpenCodeConfigPaths({ binary: "opencode", version: null })
+  const configPath = existsSync(paths.configJsonc)
+    ? paths.configJsonc
+    : existsSync(paths.configJson)
+      ? paths.configJson
+      : null
+
+  if (!configPath) {
+    return { registered: false, configPath: null }
+  }
+
+  try {
+    const parsed = parseJsonc<OpenCodeConfigShape>(readFileSync(configPath, "utf-8"))
+    const plugins = parsed.plugin ?? []
+    return { registered: plugins.some(isServerPluginEntry), configPath }
+  } catch {
+    return { registered: false, configPath }
+  }
+}
+
+export function detectTuiPluginRegistration(): TuiPluginInfo {
+  const tuiJsonPath = join(getOpenCodeConfigDir({ binary: "opencode" }), "tui.json")
+  if (!existsSync(tuiJsonPath)) {
+    return { registered: false, configPath: tuiJsonPath, exists: false }
+  }
+
+  try {
+    const parsed = parseJsonc<TuiConfigShape>(readFileSync(tuiJsonPath, "utf-8"))
+    const plugins = parsed.plugin ?? []
+    return { registered: plugins.some(isTuiPluginEntry), configPath: tuiJsonPath, exists: true }
+  } catch {
+    return { registered: false, configPath: tuiJsonPath, exists: true }
+  }
+}
+
+export async function checkTuiPluginConfig(): Promise<CheckResult> {
+  const name = CHECK_NAMES[CHECK_IDS.TUI_PLUGIN]
+  const server = detectServerPluginRegistration()
+  const tui = detectTuiPluginRegistration()
+  const issues: DoctorIssue[] = []
+  const details: string[] = []
+
+  if (server.configPath) details.push(`opencode.json: ${server.configPath}`)
+  if (tui.configPath) details.push(`tui.json: ${tui.configPath}`)
+
+  if (!server.registered && !tui.registered) {
+    return {
+      name,
+      status: "skip",
+      message: "Plugin not registered (server or TUI)",
+      details: details.length > 0 ? details : undefined,
+      issues,
+    }
+  }
+
+  if (server.registered && !tui.registered) {
+    issues.push({
+      title: "TUI plugin entry missing from tui.json",
+      description:
+        "The server plugin is registered in opencode.json, but the TUI plugin entry "
+        + `("${PLUGIN_NAME}/${TUI_SUBPATH}") is missing from tui.json. The Roles · `
+        + "Models sidebar section and TUI-only commands will not appear.",
+      fix: "Re-run the installer (`npx oh-my-openagent install`) to auto-write tui.json, "
+        + `or add "${PLUGIN_NAME}/${TUI_SUBPATH}" to the "plugin" array in ${tui.configPath}.`,
+      affects: ["TUI sidebar", "TUI commands"],
+      severity: "warning",
+    })
+    return {
+      name,
+      status: "warn",
+      message: "TUI plugin entry missing from tui.json",
+      details: details.length > 0 ? details : undefined,
+      issues,
+    }
+  }
+
+  if (!server.registered && tui.registered) {
+    issues.push({
+      title: "Server plugin entry missing from opencode.json",
+      description:
+        `The TUI plugin entry ("${PLUGIN_NAME}/${TUI_SUBPATH}") is registered in tui.json, `
+        + "but the server plugin (oh-my-openagent) is missing from opencode.json. "
+        + "The plugin cannot function correctly without both halves — the server side "
+        + "handles tool dispatch, hook execution, and SDK integration.",
+      fix: "Re-run the installer (`npx oh-my-openagent install`) to auto-write opencode.json, "
+        + `or add "${PLUGIN_NAME}" to the "plugin" array in ${server.configPath ?? "opencode.json"}.`,
+      affects: ["tool dispatch", "hook execution", "SDK integration"],
+      severity: "warning",
+    })
+    return {
+      name,
+      status: "warn",
+      message: "Server plugin entry missing from opencode.json",
+      details: details.length > 0 ? details : undefined,
+      issues,
+    }
+  }
+
+  return {
+    name,
+    status: "pass",
+    message: "Server and TUI plugin entries are both registered",
+    details: details.length > 0 ? details : undefined,
+    issues,
+  }
+}
diff --git a/src/cli/doctor/constants.ts b/src/cli/doctor/constants.ts
index dad93f8e8..f209d5901 100644
--- a/src/cli/doctor/constants.ts
+++ b/src/cli/doctor/constants.ts
@@ -21,6 +21,7 @@ export const STATUS_COLORS = {
 export const CHECK_IDS = {
   SYSTEM: "system",
   CONFIG: "config",
+  TUI_PLUGIN: "tui-plugin",
   TOOLS: "tools",
   MODELS: "models",
   TEAM_MODE: "team-mode",
@@ -29,6 +30,7 @@ export const CHECK_IDS = {
 export const CHECK_NAMES: Record<string, string> = {
   [CHECK_IDS.SYSTEM]: "System",
   [CHECK_IDS.CONFIG]: "Configuration",
+  [CHECK_IDS.TUI_PLUGIN]: "TUI Plugin",
   [CHECK_IDS.TOOLS]: "Tools",
   [CHECK_IDS.MODELS]: "Models",
   [CHECK_IDS.TEAM_MODE]: "Team Mode",