fix(startup): auto-disable a migrated preset row a plugin registers again

src/main/index.ts

@@ -39,6 +39,7 @@ import { HarnessShell } from './harness-shell'
 import { HARNESS_SHELL_URL, HARNESS_BOOT_CHANNEL, HARNESS_BOOT_FAILED_CHANNEL, isHarnessShellUrl, isHarnessBootPage } from '../shared/harness-boot'
 import {
   DEFAULT_HARNESS_PORT,
+  extractDuplicateAgentPresetId,
   extractFailureCause,
   extractPluginFailureReferences,
   HarnessRuntime,
@@ -113,7 +114,7 @@ import {
   pruneUnresolvableProfileBundles
 } from './state/plugin-recovery'
 import { ensureSafeModeProfile, SAFE_MODE_PROFILE } from './state/safe-mode-profile'
-import { migrateLegacyAgentPresets } from './state/legacy-preset-migration'
+import { disableMigratedLegacyPreset, migrateLegacyAgentPresets } from './state/legacy-preset-migration'
 import { WindowStateManager } from './state/window-state'
 import {
   isProjectedGenerationPlugin,
@@ -286,6 +287,8 @@ let webImportActionResolver: ((action: WebImportAction) => void) | undefined
 let mainWindowNavigationVersion = 0
 let rendererPluginFailureLogs: string[] = []
 let pluginRecoveryRemovedPlugins: string[] = []
+/** Migrated preset rows auto-disabled because a plugin registers the same id at runtime. */
+let autoDisabledPresetIds = new Set<string>()
 /** Plugins a deferred migration has not moved yet; their legacy copies may be manifest-only. */
 let migrationPendingPlugins = new Set<string>()
 let pluginRecoveryResetTimer: ReturnType<typeof setTimeout> | undefined
@@ -2292,6 +2295,19 @@ async function showPluginRecovery(options?: {
         timeoutMs: waitForRendererEvidence ? PLUGIN_RECOVERY_EVIDENCE_TIMEOUT_MS : 0
       })
       if (!developmentDemoUnknown) detection.plugins = evidence.targets(detection.plugins, removedPlugins)
+
+      // A preset the user's plugin registers at runtime can also live as a row the
+      // legacy migration generated; the duplicate id aborts startup and the row
+      // regenerates nothing only if it stays present. Disable that one row and
+      // relaunch: the plugin's own registration keeps the preset alive (#814).
+      const duplicatePresetId = extractDuplicateAgentPresetId(detection.logs)
+      if (duplicatePresetId && !autoDisabledPresetIds.has(duplicatePresetId)) {
+        if (await disableMigratedLegacyPreset(dshHome, duplicatePresetId, (line) => runtime.note(line))) {
+          autoDisabledPresetIds.add(duplicatePresetId)
+          await launchWithFreshEvidence()
+          continue
+        }
+      }
       // A plugin the deferred migration left manifest-only is not broken; removing
       // it would delete a working plugin because of an install-time failure. A
       // pending plugin whose legacy copy is installed can still be the culprit.

src/main/runtime/harness-runtime.ts

@@ -1024,6 +1024,17 @@ export function extractOffendingPlugins(logLines: readonly string[]): string[] {
   return extractPluginReferences(logLines, isActionablePluginReference)
 }
 
+export function extractDuplicateAgentPresetId(
+  logLines: readonly string[]
+): string | undefined {
+  for (const line of latestHarnessAttemptLogs(logLines)) {
+    if (!line.startsWith('[stderr] ')) continue
+    const match = line.slice(8).match(/Duplicate agent preset:\s*([^\s"']+)/i)
+    if (match?.[1]) return match[1].trim()
+  }
+  return undefined
+}
+
 export function extractDuplicateLoaderEntryId(
   logLines: readonly string[]
 ): string | undefined {

src/main/state/legacy-preset-migration.ts

@@ -119,3 +119,54 @@ export async function migrateLegacyAgentPresets(dshHome: string, note: (line: st
   await writeTextAtomically(profilePatch, next)
   note(`[desktop] converted ${pending.length} legacy agent presets for the web Profile; originals and backup retained`)
 }
+
+/**
+ * Disable the migrated row of one preset whose id a plugin already registers at
+ * runtime. The registry rejects a duplicate id, so startup aborts while both the
+ * row and the registration exist (#814). The row is kept — `existingIds` then
+ * still sees it as migrated and never rewrites it — but a disabled row takes no
+ * part in mounting or the startup audit, so the plugin's own registration is the
+ * single live preset on the next launch.
+ */
+
+export async function disableMigratedLegacyPreset(
+  dshHome: string,
+  presetId: string,
+  note: (line: string) => void
+): Promise<boolean> {
+  if (!PRESET_ID.test(presetId)) return false
+  const profilePatch = join(dshHome, 'profiles', 'web', 'cordis.patch.yml')
+  const previous = await readFile(profilePatch, 'utf8').catch((error: unknown) => {
+    if ((error as NodeJS.ErrnoException).code === 'ENOENT') return ''
+    throw error
+  })
+  const lines = previous.split('\n')
+  // Block boundaries by line, not index-of-string: the preset id can appear in
+  // rows outside the migrated block, and only the migrated rows are ours to edit.
+  let blockStart = -1
+  let blockEnd = -1
+  for (let index = 0; index < lines.length; index++) {
+    const line = lines[index] as string
+    if (line.includes(START)) blockStart = index
+    else if (line.includes(END)) blockEnd = index
+  }
+  if (blockStart === -1 || blockEnd === -1 || blockEnd < blockStart) return false
+
+  const wanted = `preset-${presetId}`
+  for (let index = blockStart; index <= blockEnd; index++) {
+    const match = /^(\s*)- id: (\S+)\s*$/.exec(lines[index] as string)
+    if (!match || match[2] !== wanted) continue
+    const fieldIndent = `${match[1]}  `
+    // The entry's own fields run until the next row at the entry indent.
+    for (let scan = index + 1; scan <= blockEnd; scan++) {
+      const later = lines[scan] as string
+      if (later && !later.startsWith(fieldIndent) && later.trimStart().startsWith('- ')) break
+      if (later.startsWith(`${fieldIndent}disabled:`)) return false
+    }
+    lines.splice(index + 1, 0, `${fieldIndent}disabled: true`)
+    await writeTextAtomically(profilePatch, lines.join('\n'))
+    note(`[desktop] disabled the migrated legacy preset row for "${presetId}"; a plugin registers it at runtime (#814)`)
+    return true
+  }
+  return false
+}

test/legacy-preset-migration.test.ts

@@ -2,10 +2,14 @@ import { mkdtemp, mkdir, readFile, rm, writeFile } from 'node:fs/promises'
 import { spawn } from 'node:child_process'
 import { tmpdir } from 'node:os'
 import { join, resolve } from 'node:path'
-import { afterEach, expect, it } from 'vitest'
+import { afterEach, describe, expect, it } from 'vitest'
 import jsYaml from 'js-yaml'
 import { applyEntryPatches, entryListSchema } from '@deepseek-ai/cordis-plugin-include'
-import { migrateLegacyAgentPresets } from '../src/main/state/legacy-preset-migration'
+import {
+  disableMigratedLegacyPreset,
+  migrateLegacyAgentPresets
+} from '../src/main/state/legacy-preset-migration'
+import { extractDuplicateAgentPresetId } from '../src/main/runtime/harness-runtime'
 import { HarnessRuntime } from '../src/main/runtime/harness-runtime'
 import { resolveTestNodeExecutable } from './node-executable'
 
@@ -148,3 +152,88 @@ it('publishes a migrated custom preset through the real Harness web registry', a
     await runtime.stop()
   }
 }, 45_000)
+
+describe('disableMigratedLegacyPreset', () => {
+  const homes: string[] = []
+  afterEach(async () => {
+    await Promise.all(homes.map((home) => rm(home, { recursive: true, force: true })))
+    homes.length = 0
+  })
+
+  async function patchHome(patch: string): Promise<string> {
+    const home = await mkdtemp(join(tmpdir(), 'dsh-preset-disable-'))
+    homes.push(home)
+    await mkdir(join(home, 'profiles', 'web'), { recursive: true })
+    await writeFile(join(home, 'profiles', 'web', 'cordis.patch.yml'), patch)
+    return home
+  }
+
+  it('disables only the named migrated preset row and stays idempotent', async () => {
+    const home = await patchHome(`# dsh-desktop legacy presets begin
+- insert:
+    - id: preset-aitoearn
+      name: '@deepseek-ai/dsh-agent-preset'
+      config:
+        id: aitoearn
+        plugins:
+          - aitoearn-plugin
+- insert:
+    - id: preset-other
+      name: '@deepseek-ai/dsh-agent-preset'
+      config:
+        id: other
+        plugins:
+          - other-plugin
+# dsh-desktop legacy presets end
+`)
+    const changedFirst = await disableMigratedLegacyPreset(home, 'aitoearn', () => {})
+    expect(changedFirst).toBe(true)
+    const first = await readFile(join(home, 'profiles', 'web', 'cordis.patch.yml'), 'utf8')
+    expect(first).toContain('    - id: preset-aitoearn\n      disabled: true')
+    expect(first).not.toContain('preset-other\n      disabled')
+
+    const changedSecond = await disableMigratedLegacyPreset(home, 'aitoearn', () => {})
+    expect(changedSecond).toBe(false)
+    const second = await readFile(join(home, 'profiles', 'web', 'cordis.patch.yml'), 'utf8')
+    expect(second.match(/disabled: true/g)).toHaveLength(1)
+  })
+
+  it('disables a built-in-style preset row at its own field indent', async () => {
+    const home = await patchHome(`# dsh-desktop legacy presets begin
+- id: preset-standard
+  config:
+    id: standard
+    plugins:
+      - standard-plugin
+# dsh-desktop legacy presets end
+`)
+    expect(await disableMigratedLegacyPreset(home, 'standard', () => {})).toBe(true)
+    const text = await readFile(join(home, 'profiles', 'web', 'cordis.patch.yml'), 'utf8')
+    expect(text).toContain('- id: preset-standard\n  disabled: true')
+  })
+
+  it('leaves rows outside the migration block alone', async () => {
+    const home = await patchHome(`- id: preset-aitoearn
+  config:
+    id: aitoearn
+# dsh-desktop legacy presets begin
+- insert:
+    - id: preset-real
+      name: '@deepseek-ai/dsh-agent-preset'
+# dsh-desktop legacy presets end
+`)
+    expect(await disableMigratedLegacyPreset(home, 'aitoearn', () => {})).toBe(false)
+  })
+})
+
+describe('extractDuplicateAgentPresetId', () => {
+  it('reads the duplicate preset id from the latest stderr attempt logs', () => {
+    const logs = [
+      '[stderr] older attempt: noise',
+      '[2026-10-27T00:00:00.000Z] attempt marker',
+      '[stderr] error agent-preset: Error: Duplicate agent preset: aitoearn'
+    ]
+    expect(extractDuplicateAgentPresetId(logs)).toBe('aitoearn')
+    expect(extractDuplicateAgentPresetId(['[stderr] unrelated'])).toBeUndefined()
+  })
+})