diff --git a/src/cli/handlers/worktree-gitlab-link-context.ts b/src/cli/handlers/worktree-gitlab-link-context.ts
index fe1bd6b7f56..ba78726852e 100644
--- a/src/cli/handlers/worktree-gitlab-link-context.ts
+++ b/src/cli/handlers/worktree-gitlab-link-context.ts
@@ -3,11 +3,12 @@ import type { Repo } from '../../shared/repo-types'
 import type { RuntimeWorktreeRecord } from '../../shared/runtime-types'
 import { parseGitLabIssueOrMRLink, type ProjectSlug } from '../../shared/new-workspace/gitlab-links'
 import { RuntimeClientError, type RuntimeClient } from '../runtime-client'
+import type { CliRepoTarget } from '../worktree-project-target'
 
 export async function assertGitLabLinkFlagProjectsMatch(
   flags: Map<string, string | boolean>,
   client: RuntimeClient,
-  target: { repo: string } | { worktree: string }
+  target: CliRepoTarget | { worktree: string }
 ): Promise<void> {
   const projects = ['gitlab-issue', 'gitlab-mr'].flatMap((name) => {
     const value = flags.get(name)
@@ -22,7 +23,7 @@ export async function assertGitLabLinkFlagProjectsMatch(
   }
 
   let project: ProjectSlug | null = null
-  let repo: string
+  let repoTarget: CliRepoTarget
   if ('worktree' in target) {
     const result = await client.call<{ worktree: RuntimeWorktreeRecord }>('worktree.show', target)
     const context = result.result.worktree.linkedTaskSourceContext
@@ -30,12 +31,12 @@ export async function assertGitLabLinkFlagProjectsMatch(
     if (context?.provider === 'gitlab' && identity?.provider === 'gitlab' && identity.webUrl) {
       project = parseRemoteProjectRefCandidate(identity.webUrl)
     }
-    repo = `id:${result.result.worktree.repoId}`
+    repoTarget = { repo: `id:${result.result.worktree.repoId}` }
   } else {
-    repo = target.repo
+    repoTarget = target
   }
   if (!project) {
-    const result = await client.call<{ repo: Repo }>('repo.show', { repo })
+    const result = await client.call<{ repo: Repo }>('repo.show', repoTarget)
     const remoteUrl = result.result.repo.gitRemoteIdentity?.remoteUrl
     project = remoteUrl ? parseRemoteProjectRefCandidate(remoteUrl) : null
   }
diff --git a/src/cli/handlers/worktree.ts b/src/cli/handlers/worktree.ts
index 2836528193e..75bec4b5fb0 100644
--- a/src/cli/handlers/worktree.ts
+++ b/src/cli/handlers/worktree.ts
@@ -34,7 +34,7 @@ import { projectWorktreePsTerminalVerdict } from '../worktree-ps-terminal-verdic
 import {
   assertWorkspaceTargetFlagsCompatible,
   hasWorkspaceProjectTarget,
-  getCreateRepoSelector
+  getCreateRepoTarget
 } from '../worktree-project-target'
 import {
   assertWorktreeParentFlagsCompatible,
@@ -176,8 +176,8 @@ export const WORKTREE_HANDLERS: Record<string, CommandHandler> = {
     const linearIssueLink = getOptionalLinearIssueLinkFlag(flags, 'linear-issue')
     const activate = flags.get('activate') === true || flags.get('run-hooks') === true
     const name = getRequiredStringFlag(flags, 'name')
-    const repo = await getCreateRepoSelector(flags, cwdParentWorktree, client)
-    await assertGitLabLinkFlagProjectsMatch(flags, client, { repo })
+    const repoTarget = await getCreateRepoTarget(flags, cwdParentWorktree, client)
+    await assertGitLabLinkFlagProjectsMatch(flags, client, repoTarget)
     const linkedItems = referenceInputs
       ? await resolveReferenceInputs(context, referenceInputs)
       : undefined
@@ -185,7 +185,8 @@ export const WORKTREE_HANDLERS: Record<string, CommandHandler> = {
       await assertReferenceWritesSupported(client)
     }
     const create = {
-      repo,
+      // Older hosts drop `repoHostId` and keep refusing an id on several hosts, as before.
+      ...repoTarget,
       name,
       displayName: name,
       displayNameKind: 'user',
diff --git a/src/cli/index-worktree-create-repo-host.test.ts b/src/cli/index-worktree-create-repo-host.test.ts
new file mode 100644
index 00000000000..0fbcda05b9b
--- /dev/null
+++ b/src/cli/index-worktree-create-repo-host.test.ts
@@ -0,0 +1,253 @@
+import { describe, expect, it, vi } from 'vitest'
+
+const {
+  callMock,
+  runtimeClientConstructorMock,
+  serveOrcaAppMock,
+  getDefaultUserDataPathMock,
+  addEnvironmentFromPairingCodeMock,
+  listEnvironmentsMock,
+  spawnMock
+} = vi.hoisted(() => ({
+  callMock: vi.fn(),
+  runtimeClientConstructorMock: vi.fn(),
+  serveOrcaAppMock: vi.fn(),
+  getDefaultUserDataPathMock: vi.fn(() => '/tmp/orca-user-data'),
+  addEnvironmentFromPairingCodeMock: vi.fn(),
+  listEnvironmentsMock: vi.fn(),
+  spawnMock: vi.fn()
+}))
+
+vi.mock('./runtime-client', async () => {
+  const { createRuntimeClientModuleMock } = await import('./index-test-harness.js')
+  return createRuntimeClientModuleMock({
+    callMock,
+    runtimeClientConstructorMock,
+    serveOrcaAppMock,
+    getDefaultUserDataPathMock
+  })
+})
+
+vi.mock('./runtime/environments', () => ({
+  addEnvironmentFromPairingCode: addEnvironmentFromPairingCodeMock,
+  listEnvironments: listEnvironmentsMock,
+  removeEnvironment: vi.fn(),
+  resolveEnvironment: vi.fn()
+}))
+
+vi.mock('child_process', async () => {
+  const { createChildProcessModuleMock } = await import('./index-test-harness.js')
+  return createChildProcessModuleMock(spawnMock)
+})
+
+import { main } from './index'
+import { buildWorktree, okFixture, queueFixtures, worktreeListFixture } from './test-fixtures'
+import { useWorktreeAwarenessEnvironment } from './index-test-harness'
+
+function buildSetup(overrides: { id: string; hostId: string; repoId: string; path: string }) {
+  return {
+    projectId: 'github:stablyai/orca',
+    displayName: 'Orca',
+    setupState: 'ready',
+    setupMethod: 'legacy-repo',
+    createdAt: 1,
+    updatedAt: 1,
+    ...overrides
+  }
+}
+
+// Why one repo id on two setups: a project copied between hosts keeps its id (Codex review 6 #6).
+const TWIN_SETUPS = [
+  buildSetup({ id: 'setup-1', hostId: 'local', repoId: 'repo-1', path: '/tmp/orca' }),
+  buildSetup({ id: 'setup-1', hostId: 'runtime:gpu', repoId: 'repo-1', path: '/srv/orca' })
+]
+
+describe('orca worktree create carries the selected host', () => {
+  useWorktreeAwarenessEnvironment({
+    callMock,
+    serveOrcaAppMock,
+    getDefaultUserDataPathMock,
+    addEnvironmentFromPairingCodeMock,
+    listEnvironmentsMock,
+    spawnMock
+  })
+
+  function queueCreate(): void {
+    queueFixtures(
+      callMock,
+      okFixture('req_project_setups', { setups: TWIN_SETUPS }),
+      okFixture('req_create', {
+        worktree: buildWorktree('/tmp/orca/feature', 'feature', 'abc', 'repo-1'),
+        lineage: null,
+        warnings: []
+      })
+    )
+  }
+
+  it('sends the host --project --host chose, not just the repo id', async () => {
+    queueCreate()
+    vi.spyOn(console, 'log').mockImplementation(() => {})
+
+    await main(
+      [
+        'worktree',
+        'create',
+        '--project',
+        'github:stablyai/orca',
+        '--host',
+        'local',
+        '--name',
+        'feature',
+        '--no-parent',
+        '--json'
+      ],
+      '/tmp/repo'
+    )
+
+    expect(callMock).toHaveBeenNthCalledWith(
+      2,
+      'worktree.create',
+      expect.objectContaining({ repo: 'id:repo-1', repoHostId: 'local' })
+    )
+  })
+
+  it('applies --host to a --project-host-setup id that repeats across hosts', async () => {
+    queueCreate()
+    vi.spyOn(console, 'log').mockImplementation(() => {})
+
+    await main(
+      [
+        'worktree',
+        'create',
+        '--project-host-setup',
+        'setup-1',
+        '--host',
+        'local',
+        '--name',
+        'feature',
+        '--no-parent',
+        '--json'
+      ],
+      '/tmp/repo'
+    )
+
+    expect(callMock).toHaveBeenNthCalledWith(
+      2,
+      'worktree.create',
+      expect.objectContaining({ repo: 'id:repo-1', repoHostId: 'local' })
+    )
+  })
+
+  it('asks for --host when a repeated --project-host-setup id names two hosts', async () => {
+    const logSpy = vi.spyOn(console, 'log').mockImplementation(() => {})
+    const errSpy = vi.spyOn(console, 'error').mockImplementation(() => {})
+    const priorExitCode = process.exitCode
+    queueCreate()
+
+    await main(
+      [
+        'worktree',
+        'create',
+        '--project-host-setup',
+        'setup-1',
+        '--name',
+        'feature',
+        '--no-parent',
+        '--json'
+      ],
+      '/tmp/repo'
+    )
+
+    expect(callMock).toHaveBeenCalledTimes(1)
+    const printed = [...logSpy.mock.calls, ...errSpy.mock.calls].flat().join('\n')
+    expect(printed).toContain('Ambiguous --project-host-setup setup-1')
+    expect(process.exitCode).toBe(1)
+    process.exitCode = priorExitCode
+  })
+
+  it('checks a GitLab link against the repo on the selected host', async () => {
+    queueFixtures(
+      callMock,
+      okFixture('req_project_setups', { setups: TWIN_SETUPS }),
+      okFixture('req_repo', {
+        repo: { id: 'repo-1', gitRemoteIdentity: { remoteUrl: 'https://gitlab.com/acme/app.git' } }
+      }),
+      okFixture('req_create', {
+        worktree: buildWorktree('/tmp/orca/feature', 'feature', 'abc', 'repo-1'),
+        lineage: null,
+        warnings: []
+      })
+    )
+    vi.spyOn(console, 'log').mockImplementation(() => {})
+
+    await main(
+      [
+        'worktree',
+        'create',
+        '--project',
+        'github:stablyai/orca',
+        '--host',
+        'local',
+        '--gitlab-mr',
+        'https://gitlab.com/acme/app/-/merge_requests/5',
+        '--name',
+        'feature',
+        '--no-parent',
+        '--json'
+      ],
+      '/tmp/repo'
+    )
+
+    expect(callMock).toHaveBeenNthCalledWith(2, 'repo.show', {
+      repo: 'id:repo-1',
+      repoHostId: 'local'
+    })
+    expect(callMock).toHaveBeenNthCalledWith(
+      3,
+      'worktree.create',
+      expect.objectContaining({ repo: 'id:repo-1', repoHostId: 'local' })
+    )
+  })
+
+  it('names the host when a --project-host-setup id is missing there', async () => {
+    const logSpy = vi.spyOn(console, 'log').mockImplementation(() => {})
+    const errSpy = vi.spyOn(console, 'error').mockImplementation(() => {})
+    const priorExitCode = process.exitCode
+    queueFixtures(callMock, okFixture('req_project_setups', { setups: [TWIN_SETUPS[1]] }))
+
+    await main(
+      [
+        'worktree',
+        'create',
+        '--project-host-setup',
+        'setup-1',
+        '--host',
+        'local',
+        '--name',
+        'feature',
+        '--no-parent',
+        '--json'
+      ],
+      '/tmp/repo'
+    )
+
+    const printed = [...logSpy.mock.calls, ...errSpy.mock.calls].flat().join('\n')
+    expect(printed).toContain('not ready or was not found: setup-1 on local')
+    process.exitCode = priorExitCode
+  })
+
+  it('keeps --repo selector-only', async () => {
+    queueFixtures(
+      callMock,
+      worktreeListFixture([buildWorktree('/tmp/repo', 'main', 'abc', 'repo-1')]),
+      okFixture('req_create', {
+        worktree: buildWorktree('/tmp/repo/feature', 'feature', 'abc', 'repo-1')
+      })
+    )
+    vi.spyOn(console, 'log').mockImplementation(() => {})
+
+    await main(['worktree', 'create', '--repo', 'id:repo-1', '--name', 'f', '--json'], '/tmp/repo')
+
+    expect(callMock.mock.calls[1]?.[1]).not.toHaveProperty('repoHostId')
+  })
+})
diff --git a/src/cli/index-worktree-create-target.test.ts b/src/cli/index-worktree-create-target.test.ts
index 8679b2b9257..9752a29defd 100644
--- a/src/cli/index-worktree-create-target.test.ts
+++ b/src/cli/index-worktree-create-target.test.ts
@@ -169,6 +169,7 @@ describe('orca cli worktree awareness', () => {
     expect(callMock).toHaveBeenNthCalledWith(1, 'projectHostSetup.list')
     expect(callMock).toHaveBeenNthCalledWith(2, 'worktree.create', {
       repo: 'id:repo-gpu',
+      repoHostId: 'runtime:gpu',
       name: 'feature',
       displayName: 'feature',
       displayNameKind: 'user',
diff --git a/src/cli/worktree-project-target.ts b/src/cli/worktree-project-target.ts
index 51de5d13e28..66413289be5 100644
--- a/src/cli/worktree-project-target.ts
+++ b/src/cli/worktree-project-target.ts
@@ -7,6 +7,8 @@ import { RuntimeClientError } from './runtime-client'
 
 export type ProjectCreateTarget = {
   repoSelector: string
+  /** The selected setup's host; a repo id alone is ambiguous once it is set up on two hosts. */
+  repoHostId: string
   setup: ProjectHostSetup
 }
 
@@ -44,19 +46,12 @@ export function assertWorkspaceTargetFlagsCompatible(flags: Map<string, string |
   }
 }
 
-export async function resolveProjectCreateRepoSelector(
-  flags: Map<string, string | boolean>,
-  client: RuntimeClient
-): Promise<string | undefined> {
-  return (await resolveProjectCreateTarget(flags, client))?.repoSelector
-}
-
 // Why: the routed runtime can hold both an exact `runtime:<id>` row and a `local` row for the
 // same project; the exact stamp is the one the caller named, so it wins the selection.
 function selectSetupOnHost(
   candidates: readonly ProjectHostSetup[],
   host: ParsedExecutionHost | undefined,
-  projectSelector: string | undefined
+  selectorLabel: string
 ): ProjectHostSetup | undefined {
   if (host) {
     return (
@@ -67,12 +62,12 @@ function selectSetupOnHost(
   // Why: one host is not a choice, so demanding --host for it was ceremony. Two are a choice, and
   // picking one would run the command on a machine the caller never named.
   const hostIds = new Set(candidates.map(setupHostId))
-  if (hostIds.size <= 1 || projectSelector === undefined) {
+  if (hostIds.size <= 1) {
     return candidates[0]
   }
   throw new RuntimeClientError(
     'invalid_argument',
-    `Ambiguous --project ${projectSelector}: it is set up on ${hostIds.size} hosts. Pass --host to choose one.`,
+    `Ambiguous ${selectorLabel}: it is set up on ${hostIds.size} hosts. Pass --host to choose one.`,
     {
       knownProjectHostSetups: candidates.map(summarizeSetup),
       nextSteps: [
@@ -125,14 +120,19 @@ export async function resolveProjectCreateTarget(
       : (await findProjectSetups(client, result.result.setups, projectId)).filter(
           (candidate) => candidate.setupState === 'ready'
         )
+  // Why --host applies to both: setup ids are per host, so the same id can name two setups.
   const setup = projectHostSetupId
-    ? ready.find((candidate) => candidate.id === projectHostSetupId)
-    : selectSetupOnHost(candidates, host, projectId)
+    ? selectSetupOnHost(
+        ready.filter((candidate) => candidate.id === projectHostSetupId),
+        host,
+        `--project-host-setup ${projectHostSetupId}`
+      )
+    : selectSetupOnHost(candidates, host, `--project ${projectId}`)
   if (!setup) {
     if (projectHostSetupId) {
       throw new RuntimeClientError(
         'invalid_argument',
-        `Project host setup is not ready or was not found: ${projectHostSetupId}`
+        `Project host setup is not ready or was not found: ${projectHostSetupId}${host ? ` on ${host.id}` : ''}`
       )
     }
     // Why: blaming the host when no project matched sent callers to debug the wrong flag.
@@ -162,6 +162,7 @@ export async function resolveProjectCreateTarget(
   }
   return {
     repoSelector: `id:${setup.repoId}`,
+    repoHostId: setupHostId(setup),
     setup
   }
 }
@@ -175,22 +176,28 @@ function getRepoSelectorFromWorktreeId(worktreeId: string | undefined): string |
   return `id:${worktreeId.slice(0, separatorIndex)}`
 }
 
-export async function getCreateRepoSelector(
+/**
+ * The repo a create names, as RPC params: spread it whole into every call that looks the repo up,
+ * so the host a project target picked is never dropped. `--repo` stays selector-only.
+ */
+export type CliRepoTarget = { repo: string; repoHostId?: string }
+
+export async function getCreateRepoTarget(
   flags: Map<string, string | boolean>,
   cwdParentWorktree: { worktreeId: string } | undefined,
   client: RuntimeClient
-): Promise<string> {
-  const projectRepoSelector = await resolveProjectCreateRepoSelector(flags, client)
-  if (projectRepoSelector) {
-    return projectRepoSelector
+): Promise<CliRepoTarget> {
+  const projectTarget = await resolveProjectCreateTarget(flags, client)
+  if (projectTarget) {
+    return { repo: projectTarget.repoSelector, repoHostId: projectTarget.repoHostId }
   }
   const explicitRepo = getPresentStringFlag(flags, 'repo')
   if (explicitRepo) {
-    return explicitRepo
+    return { repo: explicitRepo }
   }
   const inferredRepo = getRepoSelectorFromWorktreeId(cwdParentWorktree?.worktreeId)
   if (inferredRepo) {
-    return inferredRepo
+    return { repo: inferredRepo }
   }
   throw new RuntimeClientError(
     'invalid_argument',
diff --git a/src/main/ipc/repos/repo-ipc-wsl-move-fence.test.ts b/src/main/ipc/repos/repo-ipc-wsl-move-fence.test.ts
index fdc80d51e10..663305da3b1 100644
--- a/src/main/ipc/repos/repo-ipc-wsl-move-fence.test.ts
+++ b/src/main/ipc/repos/repo-ipc-wsl-move-fence.test.ts
@@ -16,6 +16,7 @@ import {
 import { RuntimeRepositorySettingsController } from '../../runtime/runtime-repository-settings-controller'
 import { registerFolderWorkspaceHandlers } from './folder-workspace-handlers'
 import { registerRepoCatalogHandlers } from './repo-catalog-handlers'
+import { runtimeRepoSelectorText } from '../../runtime/runtime-repo-selector'
 
 const { handlers } = vi.hoisted(() => ({
   handlers: new Map<string, (event: unknown, args: unknown) => unknown>()
@@ -133,7 +134,7 @@ describe('RuntimeRepositorySettingsController under a WSL move', () => {
     const notifyReposChanged = vi.fn()
     const controller = new RuntimeRepositorySettingsController({
       getStore: () => store,
-      resolveRepo: async (id) => repo(id),
+      resolveRepo: async (selector) => repo(runtimeRepoSelectorText(selector)),
       forgetTerminalTopology: vi.fn(),
       invalidateResolvedWorktrees: vi.fn(),
       invalidateWorktreeScan: vi.fn(),
diff --git a/src/main/runtime/construction/runtime-construction-services.ts b/src/main/runtime/construction/runtime-construction-services.ts
index c7fe2510fb8..e6c73137729 100644
--- a/src/main/runtime/construction/runtime-construction-services.ts
+++ b/src/main/runtime/construction/runtime-construction-services.ts
@@ -41,6 +41,7 @@ import type { WorkspaceSessionState } from '../../../shared/workspace-session-st
 import type { AgentStatusIpcPayload } from '../../../shared/agent-status-types'
 import type * as PtyControllerContract from '../runtime-pty-controller-contract'
 import type { RuntimeClientEventBus } from '../runtime-client-event-bus'
+import type { RuntimeRepoSelector } from '../runtime-repo-selector'
 
 export abstract class RuntimeConstructionServices {
   abstract getOrchestrationDb(): OrchestrationDb
@@ -179,7 +180,7 @@ export abstract class RuntimeConstructionServices {
     hostIds: ExecutionHostId[]
     omittedHostIds: ExecutionHostId[]
   }
-  protected abstract resolveRepoSelector(selector: string): Promise<Repo>
+  protected abstract resolveRepoSelector(selector: RuntimeRepoSelector): Promise<Repo>
   protected abstract selectReposBySelector(selector: string): Repo[]
   protected abstract listRepoWorktreesForListing(
     repo: Repo,
diff --git a/src/main/runtime/construction/runtime-file-command-state.ts b/src/main/runtime/construction/runtime-file-command-state.ts
index 9dd7b754d7b..6cc4666f013 100644
--- a/src/main/runtime/construction/runtime-file-command-state.ts
+++ b/src/main/runtime/construction/runtime-file-command-state.ts
@@ -32,6 +32,7 @@ import type { ResolvedWorktree } from '../runtime-worktree-path-identity'
 import type { Repo } from '../../../shared/repo-types'
 import { isWslMoveWorktreeBlocked } from '../../persistence/moving-wsl-projects/wsl-move-background-backoff'
 import { worktreeRowTarget } from '../../persistence/host-qualified-worktree-meta'
+import type { RuntimeRepoSelector } from '../runtime-repo-selector'
 
 export abstract class OrcaRuntimeWithFileCommands extends OrcaRuntimeWithPreservedBranchCleanup {
   abstract resolveRuntimeFileTarget(worktreeSelector: string): Promise<{
@@ -93,7 +94,7 @@ export abstract class OrcaRuntimeWithFileCommands extends OrcaRuntimeWithPreserv
 
   protected abstract resolveWorktreeSelector(selector: string): Promise<ResolvedWorktree>
 
-  protected abstract resolveRepoSelector(selector: string): Promise<Repo>
+  protected abstract resolveRepoSelector(selector: RuntimeRepoSelector): Promise<Repo>
 
   protected readonly fileCommands = new RuntimeFileCommands({
     getRuntimeId: () => this.runtimeId,
diff --git a/src/main/runtime/rpc/methods/agent-launch-worktree-creation.ts b/src/main/runtime/rpc/methods/agent-launch-worktree-creation.ts
index 2e77a987d26..5194c341bfb 100644
--- a/src/main/runtime/rpc/methods/agent-launch-worktree-creation.ts
+++ b/src/main/runtime/rpc/methods/agent-launch-worktree-creation.ts
@@ -21,7 +21,7 @@ import type { AgentLaunchWorkspaceFactory } from '../../../agent-launch/agent-la
 import { combineLaunchWarnings } from '../../../agent-launch/agent-launch-warnings'
 import type { RpcContext } from '../core'
 import { resolveRpcWorkspaceCreatorProvenance } from '../workspace-creator-context'
-import { buildManagedWorktreeCreateArgs } from './worktree-create-args'
+import { buildManagedWorktreeCreateArgs, worktreeCreateRepoSelector } from './worktree-create-args'
 import { toAgentLaunchPreferences } from '../../../../shared/agent-launch-preferences'
 import type { AgentLaunchParams } from '../../../../shared/rpc-contract/agent-launch-params'
 import { agentLaunchFolderWorkspaceCreator } from './agent-launch-folder-workspace-creation'
@@ -61,7 +61,7 @@ export function agentLaunchWorkspaceFactory(
       // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: already validated by `AgentLaunch`; the executor only removed the reserved agent fields, so the rest of the payload is the parsed shape.
       const params = create as WorktreeCreateParams
       const { runtime } = context
-      const repo = await runtime.showRepo(params.repo)
+      const repo = await runtime.showRepo(worktreeCreateRepoSelector(params))
       const automationProvenance = resolveAutomationWorkspaceProvenance({
         authority: runtime,
         repoSelector: params.repo,
diff --git a/src/main/runtime/rpc/methods/agent-launch.ts b/src/main/runtime/rpc/methods/agent-launch.ts
index a7a1217f43c..1f1fd09f680 100644
--- a/src/main/runtime/rpc/methods/agent-launch.ts
+++ b/src/main/runtime/rpc/methods/agent-launch.ts
@@ -166,8 +166,9 @@ function runLegacyAgentLaunch(
       presentation: params.presentation
     })
   if (params.target.kind === 'create-worktree' && params.target.create.clientMutationId) {
+    const { repo, repoHostId } = params.target.create
     return context.runtime.dedupeWorktreeCreate(
-      params.target.create.repo,
+      repoHostId ? { repo, repoHostId } : repo,
       `agent.launch:${params.target.create.clientMutationId}`,
       execute
     )
diff --git a/src/main/runtime/rpc/methods/repo.ts b/src/main/runtime/rpc/methods/repo.ts
index 67c942ef6da..4937527a068 100644
--- a/src/main/runtime/rpc/methods/repo.ts
+++ b/src/main/runtime/rpc/methods/repo.ts
@@ -5,7 +5,8 @@ import {
   includesQualifiedSearchRefs,
   projectRepoSearchRefsForClient
 } from './repo-search-ref-projection'
-import { RepoSelector } from '../../../../shared/rpc-contract/github-repo-target-params'
+import { RepoSelector, RepoShow } from '../../../../shared/rpc-contract/github-repo-target-params'
+import { hostQualifiedRepoSelector } from '../../runtime-repo-selector'
 import {
   projectRepoResultVisibilityForClient,
   projectRepoVisibilityForClient
@@ -172,9 +173,12 @@ export const REPO_METHODS = [
   defineMethod({
     name: 'repo.show',
     permission: 'workspace',
-    params: RepoSelector,
+    params: RepoShow,
     handler: async (params, context) => ({
-      repo: projectRepoVisibilityForClient(await context.runtime.showRepo(params.repo), context)
+      repo: projectRepoVisibilityForClient(
+        await context.runtime.showRepo(hostQualifiedRepoSelector(params.repo, params.repoHostId)),
+        context
+      )
     })
   }),
   defineMethod({
diff --git a/src/main/runtime/rpc/methods/worktree-create-args.ts b/src/main/runtime/rpc/methods/worktree-create-args.ts
index 2ee45da5f17..dd29fbc834d 100644
--- a/src/main/runtime/rpc/methods/worktree-create-args.ts
+++ b/src/main/runtime/rpc/methods/worktree-create-args.ts
@@ -2,6 +2,7 @@ import { terminalImageViewerSupported } from '../../terminal-image-viewer-env'
 import type { z } from 'zod'
 import { resolveRuntimeNavigationTarget } from '../../../../shared/runtime-navigation'
 import type { OrcaRuntimeService } from '../../orca-runtime'
+import { hostQualifiedRepoSelector, type RuntimeRepoSelector } from '../../runtime-repo-selector'
 import type { WorktreeCreate } from '../../../../shared/rpc-contract/worktree-create-params'
 
 type WorktreeCreateParams = z.infer<typeof WorktreeCreate>
@@ -11,6 +12,13 @@ type CreateProvenance = Pick<
   'automationProvenance' | 'cliProvenance' | 'creatorProvenance'
 >
 
+/** The create's repo, narrowed to `repoHostId` when the caller named one. */
+export function worktreeCreateRepoSelector(
+  params: Pick<WorktreeCreateParams, 'repo' | 'repoHostId'>
+): RuntimeRepoSelector {
+  return hostQualifiedRepoSelector(params.repo, params.repoHostId)
+}
+
 /** Wire params → runtime create args. Kept out of the method table so the mapping can grow with
  *  the schema without the table becoming unreadable. */
 export function buildManagedWorktreeCreateArgs(
@@ -20,7 +28,7 @@ export function buildManagedWorktreeCreateArgs(
 ): ManagedWorktreeCreateArgs {
   const viewerSupported = origin && terminalImageViewerSupported(origin)
   return {
-    repoSelector: params.repo,
+    repoSelector: worktreeCreateRepoSelector(params),
     // A phone's retry key is the identity of its creation.
     creationId: params.creationId ?? params.clientMutationId,
     ...(viewerSupported !== undefined ? { terminalImageViewerSupported: viewerSupported } : {}),
diff --git a/src/main/runtime/rpc/methods/worktree.ts b/src/main/runtime/rpc/methods/worktree.ts
index 153824e48da..7f48b08048b 100644
--- a/src/main/runtime/rpc/methods/worktree.ts
+++ b/src/main/runtime/rpc/methods/worktree.ts
@@ -11,7 +11,7 @@ import { displayNameUpdatePinsLabel } from '../../../../shared/worktree/display-
 import { getWorkspaceStatusWarning } from '../../../../shared/workspace-status-warning'
 import { createWorktreeWithStartupAgent } from '../../../agent-launch/startup-agent-worktree-create'
 import { defineMethod } from '../core'
-import { buildManagedWorktreeCreateArgs } from './worktree-create-args'
+import { buildManagedWorktreeCreateArgs, worktreeCreateRepoSelector } from './worktree-create-args'
 import { resolvePairedCallerHostId } from './paired-caller-host-id'
 import { resolveRuntimeNavigationTarget } from '../../../../shared/runtime-navigation'
 import { resolveRpcWorkspaceCreatorProvenance } from '../workspace-creator-context'
@@ -96,9 +96,9 @@ export const WORKTREE_METHODS = [
       // Why: a mobile create interrupted by a connection migration is retried with
       // the same clientMutationId; dedupe so the host returns the in-flight/created
       // worktree instead of spawning a duplicate. No key (desktop/CLI) runs plainly.
-      context.runtime.dedupeWorktreeCreate(params.repo, params.clientMutationId, async () => {
+      context.runtime.dedupeWorktreeCreate(params, params.clientMutationId, async () => {
         const { runtime } = context
-        const repo = await runtime.showRepo(params.repo)
+        const repo = await runtime.showRepo(worktreeCreateRepoSelector(params))
         const automationProvenance = resolveAutomationWorkspaceProvenance({
           authority: runtime,
           repoSelector: params.repo,
diff --git a/src/main/runtime/runtime-managed-worktree-create-types.ts b/src/main/runtime/runtime-managed-worktree-create-types.ts
index 53ac465c4df..77eb0e3b6f8 100644
--- a/src/main/runtime/runtime-managed-worktree-create-types.ts
+++ b/src/main/runtime/runtime-managed-worktree-create-types.ts
@@ -14,9 +14,10 @@ import type { WorktreeStartupLaunch } from '../../shared/worktree/launch-types'
 import type { TaskSourceContext } from '../../shared/task-source-context'
 import type { WorktreeStartupDraftPaste } from './runtime-worktree-agent-startup'
 import type { RuntimeNavigationTarget } from '../../shared/runtime-navigation'
+import type { RuntimeRepoSelector } from './runtime-repo-selector'
 
 export type RuntimeManagedWorktreeCreateArgs = {
-  repoSelector: string
+  repoSelector: RuntimeRepoSelector
   name: string
   nameWasGenerated?: boolean
   navigation?: RuntimeNavigationTarget
diff --git a/src/main/runtime/runtime-repo-selector.ts b/src/main/runtime/runtime-repo-selector.ts
new file mode 100644
index 00000000000..840d665a428
--- /dev/null
+++ b/src/main/runtime/runtime-repo-selector.ts
@@ -0,0 +1,27 @@
+import type { ExecutionHostId } from '../../shared/execution-host'
+
+/**
+ * A repo selector, optionally narrowed to one host. One repo id can be set up on several hosts, so
+ * the host travels with the selector: every lookup that re-resolves it keeps the caller's choice.
+ */
+export type RuntimeRepoSelector =
+  | string
+  | { readonly selector: string; readonly hostId: ExecutionHostId }
+
+/** The wire pair (`repo`, optional `repoHostId`) as one selector; absent host keeps the old string. */
+export function hostQualifiedRepoSelector(
+  selector: string,
+  hostId: ExecutionHostId | undefined
+): RuntimeRepoSelector {
+  return hostId ? { selector, hostId } : selector
+}
+
+export function runtimeRepoSelectorText(selector: RuntimeRepoSelector): string {
+  return typeof selector === 'string' ? selector : selector.selector
+}
+
+export function runtimeRepoSelectorHostId(
+  selector: RuntimeRepoSelector
+): ExecutionHostId | undefined {
+  return typeof selector === 'string' ? undefined : selector.hostId
+}
diff --git a/src/main/runtime/runtime-repository-settings-controller.ts b/src/main/runtime/runtime-repository-settings-controller.ts
index 559200ffba1..29593d7fb51 100644
--- a/src/main/runtime/runtime-repository-settings-controller.ts
+++ b/src/main/runtime/runtime-repository-settings-controller.ts
@@ -1,6 +1,7 @@
 import { isFolderRepo } from '../../shared/repo-kind'
 import { commitProvenRepoKindChange } from '../folder-repo-git-conversion'
 import type { Repo } from '../../shared/repo-types'
+import type { RuntimeRepoSelector } from './runtime-repo-selector'
 import type { GhAccountBinding } from '../../shared/github/account-binding'
 import { invalidateAuthorizedRootsCache } from '../ipc/registered-worktree-roots-cache'
 import { prepareLocalWorktreeRootForRepo } from '../worktree-root-preparation'
@@ -12,7 +13,7 @@ const PROJECT_TERMINAL_STOP_BUDGET_MS = 10_000
 
 type RuntimeRepositorySettingsDependencies = {
   getStore: () => RuntimeStore | null
-  resolveRepo: (selector: string) => Promise<Repo>
+  resolveRepo: (selector: RuntimeRepoSelector) => Promise<Repo>
   forgetTerminalTopology: (repoId: string) => void
   /** Optional so test doubles and older wiring keep removing without it. */
   stopProjectTerminals?: (
@@ -62,7 +63,7 @@ function omitUndefined<T extends Record<string, unknown>>(value: T): Partial<T>
 export class RuntimeRepositorySettingsController {
   constructor(private readonly deps: RuntimeRepositorySettingsDependencies) {}
 
-  async show(repoSelector: string): Promise<Repo> {
+  async show(repoSelector: RuntimeRepoSelector): Promise<Repo> {
     return await this.deps.resolveRepo(repoSelector)
   }
 
diff --git a/src/main/runtime/runtime-worktree-create-repo-host.test.ts b/src/main/runtime/runtime-worktree-create-repo-host.test.ts
new file mode 100644
index 00000000000..d8e3e584432
--- /dev/null
+++ b/src/main/runtime/runtime-worktree-create-repo-host.test.ts
@@ -0,0 +1,121 @@
+import './rpc/unused-default-rpc-methods.test-fixture'
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import type { Repo } from '../../shared/repo-types'
+import { RpcDispatcher } from './rpc/dispatcher'
+import type { RpcContext, RpcRequest } from './rpc/core'
+import { REPO_METHODS } from './rpc/methods/repo'
+import { WORKTREE_METHODS } from './rpc/methods/worktree'
+import { agentLaunchWorkspaceFactory } from './rpc/methods/agent-launch-worktree-creation'
+import { OrcaRuntimeService } from './orca-runtime'
+
+// Why twins: a project copied between hosts keeps its repo id (Codex review 6 #6).
+const REPOS: Repo[] = [
+  {
+    id: 'dup',
+    path: '/laptop/dup',
+    displayName: 'Dup',
+    badgeColor: '#000',
+    addedAt: 1,
+    kind: 'git',
+    executionHostId: 'local'
+  },
+  {
+    id: 'dup',
+    path: '/remote/dup',
+    displayName: 'Dup',
+    badgeColor: '#000',
+    addedAt: 2,
+    kind: 'git',
+    executionHostId: 'ssh:gpu'
+  }
+]
+
+function createRuntime(): OrcaRuntimeService {
+  // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: these paths stop right after repo resolution, which reads only these store methods.
+  return new OrcaRuntimeService({
+    getRepos: () => REPOS,
+    getRepo: (id: string) => REPOS.find((repo) => repo.id === id) ?? null,
+    getAllWorktreeMeta: () => ({}),
+    getWorktreeMeta: () => null,
+    setWorktreeMeta: vi.fn(),
+    getGitHubCache: () => null,
+    getSettings: () => ({})
+  } as never)
+}
+
+/** Stops every create at the step that receives the resolved repo, and records that repo. */
+function stopAtResolvedProject() {
+  return vi
+    .spyOn(
+      // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: spies on the private step that receives the resolved repo; it exists on the prototype.
+      OrcaRuntimeService.prototype as unknown as {
+        createInResolvedProject: (args: unknown, repo: Repo) => Promise<never>
+      },
+      'createInResolvedProject'
+    )
+    .mockRejectedValue(new Error('stop after resolution'))
+}
+
+function request(method: string, params: unknown): RpcRequest {
+  return { id: 'req-1', authToken: 'tok', method, params }
+}
+
+describe('a repo id set up on two hosts, named with repoHostId', () => {
+  afterEach(() => {
+    vi.restoreAllMocks()
+  })
+
+  it('repo.show resolves the row on the named host and still refuses a bare id', async () => {
+    const dispatcher = new RpcDispatcher({ runtime: createRuntime(), methods: REPO_METHODS })
+
+    const named = await dispatcher.dispatch(
+      request('repo.show', { repo: 'id:dup', repoHostId: 'ssh:gpu' })
+    )
+    const bare = await dispatcher.dispatch(request('repo.show', { repo: 'id:dup' }))
+
+    expect(named).toMatchObject({ ok: true, result: { repo: { path: '/remote/dup' } } })
+    expect(bare).toMatchObject({ ok: false, error: { code: 'selector_ambiguous' } })
+  })
+
+  it.each([
+    ['plain', {}],
+    ['with a startup agent', { startupAgent: 'claude' }],
+    ['with a linked startup draft', { startupDraft: 'Fix the bug' }]
+  ])('worktree.create keeps the host through every lookup (%s)', async (_label, extra) => {
+    const reached = stopAtResolvedProject()
+    const dispatcher = new RpcDispatcher({ runtime: createRuntime(), methods: WORKTREE_METHODS })
+
+    await dispatcher.dispatch(
+      request('worktree.create', { repo: 'id:dup', repoHostId: 'local', name: 'x', ...extra })
+    )
+
+    expect(reached).toHaveBeenCalledTimes(1)
+    expect(reached.mock.calls[0]?.[1]).toMatchObject({ path: '/laptop/dup' })
+  })
+
+  it('agent.launch create-worktree keeps the host', async () => {
+    const reached = stopAtResolvedProject()
+    const runtime = createRuntime()
+    // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: the create reads only `runtime` and the creator-provenance fields, which default when absent.
+    const factory = agentLaunchWorkspaceFactory({ runtime } as unknown as RpcContext, 'claude')
+
+    await expect(
+      factory.createWorktree({
+        create: { repo: 'id:dup', repoHostId: 'ssh:gpu', name: 'x' },
+        startupAgent: 'claude'
+      })
+    ).rejects.toThrow('stop after resolution')
+
+    expect(reached.mock.calls[0]?.[1]).toMatchObject({ path: '/remote/dup' })
+  })
+
+  it('a retried create for one host never coalesces with the same retry for another', async () => {
+    const runtime = createRuntime()
+    const run = vi.fn(async () => 'created')
+
+    await runtime.dedupeWorktreeCreate({ repo: 'id:dup', repoHostId: 'local' }, 'retry-1', run)
+    await runtime.dedupeWorktreeCreate({ repo: 'id:dup', repoHostId: 'ssh:gpu' }, 'retry-1', run)
+
+    expect(run).toHaveBeenCalledTimes(2)
+  })
+})
diff --git a/src/main/runtime/terminal/launch/terminal-create-deduplication.ts b/src/main/runtime/terminal/launch/terminal-create-deduplication.ts
index 7298e71a792..1d77b402e00 100644
--- a/src/main/runtime/terminal/launch/terminal-create-deduplication.ts
+++ b/src/main/runtime/terminal/launch/terminal-create-deduplication.ts
@@ -9,7 +9,8 @@ import { getRegisteredSshState } from '../../../ssh/targets/ssh-target-registry'
 import {
   getConnectionExecutionHostId,
   LOCAL_EXECUTION_HOST_ID,
-  toSshExecutionHostId
+  toSshExecutionHostId,
+  type ExecutionHostId
 } from '../../../../shared/execution-host'
 import { resolveWorktreeLaunchHost } from '../../worktree-launch-host-repo'
 import type { TuiAgent } from '../../../../shared/tui-agent'
@@ -196,14 +197,21 @@ export abstract class OrcaRuntimeWithTerminalCreateDeduplication extends OrcaRun
   // drop immediately so a genuine retry starts fresh, and successes linger
   // briefly so a retry whose response was lost in the cutover still reconciles.
   dedupeWorktreeCreate<T>(
-    repoSelector: string,
+    target: string | { repo: string; repoHostId?: ExecutionHostId },
     clientMutationId: string | undefined,
     run: () => Promise<T>
   ): Promise<T> {
     if (!clientMutationId) {
       return run()
     }
-    const key = `${repoSelector}\0${clientMutationId}`
+    // Why the host: two creates for one repo id on different hosts are different creates.
+    const repoKey =
+      typeof target === 'string'
+        ? target
+        : target.repoHostId
+          ? `${target.repoHostId}\0${target.repo}`
+          : target.repo
+    const key = `${repoKey}\0${clientMutationId}`
     const inflight = this.worktreeCreateByMutationId.get(key)
     if (inflight) {
       // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: Callers must use one operation/result type per repo and mutation key.
diff --git a/src/main/runtime/workspaces/workspace-selectors.ts b/src/main/runtime/workspaces/workspace-selectors.ts
index 57c67b33a8e..155f03f02d2 100644
--- a/src/main/runtime/workspaces/workspace-selectors.ts
+++ b/src/main/runtime/workspaces/workspace-selectors.ts
@@ -3,6 +3,11 @@ import type { ResolvedWorktree } from '../runtime-worktree-path-identity'
 import { splitWorktreeIdForFilesystem, worktreeIdentityKey } from '../../../shared/worktree/id'
 import { branchSelectorMatches, runtimePathsEqual } from '../runtime-worktree-path-identity'
 import { getRepoExecutionHostId, getWorktreeExecutionHostId } from '../../../shared/execution-host'
+import {
+  runtimeRepoSelectorHostId,
+  runtimeRepoSelectorText,
+  type RuntimeRepoSelector
+} from '../runtime-repo-selector'
 import type {
   WorktreeLineageInput,
   WorktreeLineageResolution
@@ -172,11 +177,15 @@ export abstract class RuntimeWorkspaceSelectors extends OrcaRuntimeWithResolveBr
     )
   }
 
-  protected async resolveRepoSelector(selector: string): Promise<Repo> {
+  protected async resolveRepoSelector(selector: RuntimeRepoSelector): Promise<Repo> {
     if (!this.store) {
       throw new Error('repo_not_found')
     }
-    const candidates = this.selectReposBySelector(selector)
+    const matches = this.selectReposBySelector(runtimeRepoSelectorText(selector))
+    const hostId = runtimeRepoSelectorHostId(selector)
+    const candidates = hostId
+      ? matches.filter((repo) => getRepoExecutionHostId(repo) === hostId)
+      : matches
 
     if (candidates.length === 1) {
       return candidates[0]
diff --git a/src/shared/rpc-contract/github-repo-target-params.ts b/src/shared/rpc-contract/github-repo-target-params.ts
index 199e90ad388..c8a9135dc67 100644
--- a/src/shared/rpc-contract/github-repo-target-params.ts
+++ b/src/shared/rpc-contract/github-repo-target-params.ts
@@ -1,10 +1,14 @@
 import { z } from 'zod'
 import { OptionalString, requiredString } from './rpc-param-primitives'
+import { OptionalExecutionHostId } from './worktree-params'
 
 export const RepoSelector = z.object({
   repo: requiredString('Missing repo selector')
 })
 
+/** `repo.show`: `repoHostId` narrows a repo id set up on several hosts; older hosts drop it. */
+export const RepoShow = RepoSelector.extend({ repoHostId: OptionalExecutionHostId })
+
 export const SlugRepo = z.object({
   owner: requiredString('Missing owner'),
   repo: requiredString('Missing repo'),
diff --git a/src/shared/rpc-contract/rpc-params-catalog.generated.ts b/src/shared/rpc-contract/rpc-params-catalog.generated.ts
index 5052e1b4e98..e3672b9326b 100644
--- a/src/shared/rpc-contract/rpc-params-catalog.generated.ts
+++ b/src/shared/rpc-contract/rpc-params-catalog.generated.ts
@@ -289,7 +289,7 @@ import {
   UpdatePrState,
   UpdatePrTitle
 } from './github-pull-request-update-params'
-import { RepoSelector, SlugRepo } from './github-repo-target-params'
+import { RepoSelector, RepoShow, SlugRepo } from './github-repo-target-params'
 import {
   IssuesList,
   RateLimit,
@@ -1252,7 +1252,7 @@ export const RPC_PARAMS_BY_METHOD = {
   'repo.searchRefs': RepoSearchRefs,
   'repo.setBaseRef': RepoSetBaseRef,
   'repo.setupScriptImports': RepoSelector,
-  'repo.show': RepoSelector,
+  'repo.show': RepoShow,
   'repo.sparsePresets': RepoSelector,
   'repo.update': RepoUpdate,
   'runtime.automaticWork.resume': null,
diff --git a/src/shared/rpc-contract/worktree-create-params.ts b/src/shared/rpc-contract/worktree-create-params.ts
index a492b78a0b2..d026d67980b 100644
--- a/src/shared/rpc-contract/worktree-create-params.ts
+++ b/src/shared/rpc-contract/worktree-create-params.ts
@@ -16,6 +16,7 @@ import {
 import {
   AutomationWorkspaceProvenanceRequest,
   CliWorkspaceProvenanceRequest,
+  OptionalExecutionHostId,
   OptionalTuiAgent,
   assertLinkedWorkItemSourceContextMatch
 } from './worktree-params'
@@ -26,6 +27,9 @@ export const WorktreeCreate = z
       .unknown()
       .transform((v) => (typeof v === 'string' ? v : ''))
       .pipe(z.string().min(1, 'Missing repo selector')),
+    /** The host of the repo row `repo` names: one repo id can be set up on several hosts. Absent
+     *  (older clients) keeps the selector-only lookup, which refuses an id on several hosts. */
+    repoHostId: OptionalExecutionHostId,
     name: OptionalString,
     /** Set by clients that fell back to a generated creature name. Absent means user-typed, so the
      *  host neither skips a retired candidate nor retires the name it lands on. */