Fix Antigravity source-control model discovery and retired defaults (#21606)

* fix(antigravity): discover current source-control models and use CLI defaults

* fix(antigravity): gate configured models on remote runtime support

* fix(runtime): forward default TUI agent for remote git generation

* test(runtime): cover inherited agent forwarding

src/main/runtime/rpc/methods/git-commit-message-generation-methods.ts

@@ -13,6 +13,7 @@ type CommitMessageGenerationOverride = {
   sourceControlAi?: GlobalSettings['sourceControlAi']
   sourceControlAiResolvedParams?: ResolvedSourceControlAiGenerationParams
   agentCmdOverrides?: GlobalSettings['agentCmdOverrides']
+  defaultTuiAgent?: GlobalSettings['defaultTuiAgent']
   commitMessageDiscoveryHostKey?: string
 }
 
@@ -23,6 +24,7 @@ function buildCommitMessageGenerationOverride(params: {
   sourceControlAi?: unknown
   sourceControlAiResolvedParams?: unknown
   agentCmdOverrides?: unknown
+  defaultTuiAgent?: GlobalSettings['defaultTuiAgent']
   commitMessageDiscoveryHostKey?: string
 }): CommitMessageGenerationOverride | undefined {
   if (
@@ -30,6 +32,7 @@ function buildCommitMessageGenerationOverride(params: {
     params.sourceControlAi === undefined &&
     params.sourceControlAiResolvedParams === undefined &&
     params.agentCmdOverrides === undefined &&
+    params.defaultTuiAgent === undefined &&
     params.commitMessageDiscoveryHostKey === undefined
   ) {
     return undefined
@@ -52,6 +55,7 @@ function buildCommitMessageGenerationOverride(params: {
           agentCmdOverrides: params.agentCmdOverrides as GlobalSettings['agentCmdOverrides']
         }
       : {}),
+    ...(params.defaultTuiAgent !== undefined ? { defaultTuiAgent: params.defaultTuiAgent } : {}),
     ...(params.commitMessageDiscoveryHostKey !== undefined
       ? { commitMessageDiscoveryHostKey: params.commitMessageDiscoveryHostKey }
       : {})

src/main/runtime/runtime-git-generation-context.ts

@@ -48,7 +48,10 @@ export function pullRequestDraftGitExec(
 }
 
 export type RuntimeCommitMessageSettingsOverride = Partial<
-  Pick<GlobalSettings, 'commitMessageAi' | 'sourceControlAi' | 'agentCmdOverrides'>
+  Pick<
+    GlobalSettings,
+    'commitMessageAi' | 'sourceControlAi' | 'agentCmdOverrides' | 'defaultTuiAgent'
+  >
 > & {
   commitMessageDiscoveryHostKey?: string
   sourceControlAiResolvedParams?: ResolvedSourceControlAiGenerationParams

src/renderer/src/components/settings/source-control-action-recipe-options.ts

@@ -59,6 +59,7 @@ export const getActionDescriptions = createLocalizedCatalog(
 const FALLBACK_AGENT_ARGS_PLACEHOLDER = '--model sonnet'
 
 const AGENT_ARGS_PLACEHOLDER_OVERRIDES: Partial<Record<TuiAgent, string>> = {
+  antigravity: '--effort low',
   // Why: Source Control AI action prompts are short, reviewable tasks; the
   // mini Codex model is a better default hint than the frontier model.
   codex: '--model gpt-5.4-mini',

src/renderer/src/runtime/antigravity-generation-compatibility.test.ts

@@ -0,0 +1,93 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { getDefaultSettings } from '../../../shared/constants'
+import { ANTIGRAVITY_CONFIGURED_MODEL_RUNTIME_CAPABILITY } from '../../../shared/protocol-version'
+import {
+  generateRuntimeCommitMessage,
+  generateRuntimePullRequestFields
+} from './runtime-git-generation-client'
+
+const mocks = vi.hoisted(() => ({ supports: vi.fn(), rpc: vi.fn() }))
+vi.mock('./runtime-rpc-client', () => ({
+  getActiveRuntimeTarget: () => ({ kind: 'environment', environmentId: 'remote-test' }),
+  runtimeEnvironmentSupportsCapability: mocks.supports,
+  callRuntimeRpc: mocks.rpc
+}))
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  mocks.supports.mockResolvedValue(false)
+  mocks.rpc.mockResolvedValue({ success: true })
+})
+
+for (const operation of ['commitMessage', 'pullRequest'] as const) {
+  describe(operation, () => {
+    function generate(model: string, resolved = true, agentArgs?: string) {
+      const settings = getDefaultSettings('/tmp')
+      settings.activeRuntimeEnvironmentId = 'remote-test'
+      settings.sourceControlAi = { ...settings.sourceControlAi!, agentId: 'antigravity' }
+      const context = { settings, worktreeId: 'wt-1', worktreePath: '/remote/workspace' }
+      const overrides = resolved
+        ? {
+            sourceControlAiResolvedParams: {
+              agentId: 'antigravity' as const,
+              model,
+              ...(agentArgs ? { agentArgs } : {})
+            }
+          }
+        : undefined
+      return operation === 'commitMessage'
+        ? generateRuntimeCommitMessage(context, overrides)
+        : generateRuntimePullRequestFields(
+            context,
+            { base: 'main', title: '', body: '', draft: true },
+            overrides
+          )
+    }
+
+    it('does not send the new default sentinel to an older server', async () => {
+      expect(await generate('default')).toMatchObject({
+        success: false,
+        error: expect.stringContaining('Update the remote server')
+      })
+      expect(mocks.rpc).not.toHaveBeenCalled()
+      expect(mocks.supports).toHaveBeenCalledWith(
+        'remote-test',
+        ANTIGRAVITY_CONFIGURED_MODEL_RUNTIME_CAPABILITY
+      )
+    })
+
+    it('guards settings-derived defaults as well as one-shot selections', async () => {
+      expect(await generate('default', false)).toMatchObject({ success: false })
+      expect(mocks.rpc).not.toHaveBeenCalled()
+    })
+
+    it('sends the unchanged selection to a server that supports the configured model', async () => {
+      mocks.supports.mockResolvedValue(true)
+      expect(await generate('default')).toMatchObject({ success: true })
+      expect(mocks.rpc).toHaveBeenCalledWith(
+        { kind: 'environment', environmentId: 'remote-test' },
+        operation === 'commitMessage'
+          ? 'git.generateCommitMessage'
+          : 'git.generatePullRequestFields',
+        expect.objectContaining({
+          sourceControlAiResolvedParams: { agentId: 'antigravity', model: 'default' }
+        }),
+        expect.anything()
+      )
+    })
+
+    it('keeps explicit models usable on older servers without requiring the new capability', async () => {
+      expect(await generate('gemini-3.8-flash-low')).toMatchObject({ success: true })
+      expect(mocks.supports).not.toHaveBeenCalled()
+      expect(mocks.rpc).toHaveBeenCalledTimes(1)
+    })
+
+    it('accepts an explicit model supplied through the recipe CLI arguments', async () => {
+      expect(await generate('default', true, '--model gemini-3.8-flash-low')).toMatchObject({
+        success: true
+      })
+      expect(mocks.supports).not.toHaveBeenCalled()
+      expect(mocks.rpc).toHaveBeenCalledTimes(1)
+    })
+  })
+}

src/renderer/src/runtime/antigravity-generation-compatibility.ts

@@ -0,0 +1,52 @@
+import { ANTIGRAVITY_CONFIGURED_MODEL_RUNTIME_CAPABILITY } from '../../../shared/protocol-version'
+import { hasFlag } from '../../../shared/agent-cli-flag-detection'
+import { planCommitMessageGeneration } from '../../../shared/commit-message-plan'
+import { resolveSourceControlAiForOperation } from '../../../shared/source-control-ai'
+import {
+  getRuntimeCommitMessageSettings,
+  type RuntimeGitContext,
+  type RuntimeGenerateCommitMessageOverrides
+} from './runtime-git-client-context'
+import { runtimeEnvironmentSupportsCapability } from './runtime-rpc-client'
+
+export async function antigravityGenerationCompatibilityError(
+  environmentId: string,
+  context: RuntimeGitContext,
+  operation: 'commitMessage' | 'pullRequest',
+  overrides?: RuntimeGenerateCommitMessageOverrides
+): Promise<string | null> {
+  let params = overrides?.sourceControlAiResolvedParams
+  if (!params) {
+    const settings = getRuntimeCommitMessageSettings(context.settings, context.connectionId)
+    const resolved = resolveSourceControlAiForOperation({
+      settings: {
+        ...settings,
+        defaultTuiAgent: context.settings?.defaultTuiAgent ?? null,
+        sourceControlAi: overrides?.sourceControlAi ?? settings.sourceControlAi,
+        agentCmdOverrides: overrides?.agentCmdOverrides ?? settings.agentCmdOverrides ?? {}
+      },
+      operation,
+      discoveryHostKey: settings.commitMessageDiscoveryHostKey
+    })
+    if (resolved.ok) {
+      params = resolved.value.params
+    }
+  }
+  if (params?.agentId !== 'antigravity' || params.model !== 'default') {
+    return null
+  }
+  const planned = planCommitMessageGeneration(params, '')
+  // A recipe or command override can already supply a model that older planners understand.
+  if (planned.ok && hasFlag(planned.plan.args, ['--model'])) {
+    return null
+  }
+  if (
+    await runtimeEnvironmentSupportsCapability(
+      environmentId,
+      ANTIGRAVITY_CONFIGURED_MODEL_RUNTIME_CAPABILITY
+    )
+  ) {
+    return null
+  }
+  return 'This remote Orca server does not support Antigravity’s configured model. Update the remote server or select an explicit Antigravity model.'
+}

src/renderer/src/runtime/runtime-git-client-context.ts

@@ -32,7 +32,12 @@ export type RuntimePullRequestGenerationInput = {
 }
 
 export type RuntimeGitSettings = Pick<GlobalSettings, 'activeRuntimeEnvironmentId'> &
-  Partial<Pick<GlobalSettings, 'commitMessageAi' | 'sourceControlAi' | 'agentCmdOverrides'>>
+  Partial<
+    Pick<
+      GlobalSettings,
+      'commitMessageAi' | 'sourceControlAi' | 'agentCmdOverrides' | 'defaultTuiAgent'
+    >
+  >
 
 export type RuntimeDiscoverCommitMessageModelsResult =
   | {
@@ -77,7 +82,12 @@ export function getRuntimeGitScope(
 export function getRuntimeCommitMessageSettings(
   settings: RuntimeGitSettings | null | undefined,
   connectionId?: string
-): Partial<Pick<GlobalSettings, 'commitMessageAi' | 'sourceControlAi' | 'agentCmdOverrides'>> & {
+): Partial<
+  Pick<
+    GlobalSettings,
+    'commitMessageAi' | 'sourceControlAi' | 'agentCmdOverrides' | 'defaultTuiAgent'
+  >
+> & {
   commitMessageDiscoveryHostKey?: string
 } {
   if (!settings) {
@@ -94,6 +104,9 @@ export function getRuntimeCommitMessageSettings(
     ...(settings.agentCmdOverrides !== undefined
       ? { agentCmdOverrides: settings.agentCmdOverrides }
       : {}),
+    ...(settings.defaultTuiAgent !== undefined
+      ? { defaultTuiAgent: settings.defaultTuiAgent }
+      : {}),
     commitMessageDiscoveryHostKey: getCommitMessageModelDiscoveryHostKeyForScope(scope)
   }
 }

src/renderer/src/runtime/runtime-git-client.test.ts

@@ -721,6 +721,7 @@ describe('runtime git client', () => {
     await generateRuntimeCommitMessage({
       settings: {
         activeRuntimeEnvironmentId: 'env-1',
+        defaultTuiAgent: 'codex',
         commitMessageAi,
         agentCmdOverrides
       },
@@ -733,6 +734,7 @@ describe('runtime git client', () => {
       method: 'git.generateCommitMessage',
       params: {
         worktree: 'id:wt-1',
+        defaultTuiAgent: 'codex',
         commitMessageAi,
         agentCmdOverrides,
         commitMessageDiscoveryHostKey: 'runtime:env-1'

src/renderer/src/runtime/runtime-git-generation-client.ts

@@ -1,4 +1,5 @@
 import { getRepoIdFromWorktreeId } from '../../../shared/worktree/id'
+import { antigravityGenerationCompatibilityError } from './antigravity-generation-compatibility'
 import {
   getRuntimeCommitMessageSettings,
   resolveLocalWorktreePath,
@@ -32,6 +33,15 @@ export async function generateRuntimeCommitMessage(
       ...(overrides?.agentCmdOverrides ? { agentCmdOverrides: overrides.agentCmdOverrides } : {})
     }) as Promise<RuntimeGenerateCommitMessageResult>
   }
+  const compatibilityError = await antigravityGenerationCompatibilityError(
+    target.environmentId,
+    context,
+    'commitMessage',
+    overrides
+  )
+  if (compatibilityError) {
+    return { success: false, error: compatibilityError }
+  }
   return callRuntimeRpc<RuntimeGenerateCommitMessageResult>(
     target,
     'git.generateCommitMessage',
@@ -114,6 +124,15 @@ export async function generateRuntimePullRequestFields(
       ...(overrides?.agentCmdOverrides ? { agentCmdOverrides: overrides.agentCmdOverrides } : {})
     }) as Promise<RuntimeGeneratePullRequestFieldsResult>
   }
+  const compatibilityError = await antigravityGenerationCompatibilityError(
+    target.environmentId,
+    context,
+    'pullRequest',
+    overrides
+  )
+  if (compatibilityError) {
+    return { success: false, error: compatibilityError }
+  }
   return callRuntimeRpc<RuntimeGeneratePullRequestFieldsResult>(
     target,
     'git.generatePullRequestFields',

src/shared/antigravity-source-control.test.ts

@@ -0,0 +1,65 @@
+import { describe, expect, it } from 'vitest'
+import { getDefaultSettings } from './constants'
+import { resolveSourceControlAiForOperation } from './source-control-ai'
+import { planCommitMessageGeneration } from './commit-message-plan'
+
+describe('Antigravity source-control model selection', () => {
+  for (const host of ['local', 'ssh:verification-host']) {
+    for (const operation of ['commitMessage', 'branchName', 'pullRequest'] as const) {
+      it(`${operation} on ${host} falls back from a retired saved model to the CLI configuration`, () => {
+        const settings = getDefaultSettings('/tmp')
+        settings.sourceControlAi = {
+          ...settings.sourceControlAi!,
+          enabled: true,
+          agentId: 'antigravity',
+          selectedModelByAgent: { antigravity: 'Gemini 3.5 Flash (Medium)' },
+          selectedModelByAgentByHost: {
+            [host]: { antigravity: 'Gemini 3.5 Flash (Medium)' }
+          },
+          discoveredModelsByAgent: {},
+          discoveredModelsByAgentByHost: {}
+        }
+        const result = resolveSourceControlAiForOperation({
+          settings,
+          repo: null,
+          operation,
+          discoveryHostKey: host
+        })
+        expect(result.ok).toBe(true)
+        if (!result.ok) {
+          throw new Error(result.error)
+        }
+        expect(result.value.params.model).toBe('default')
+        const plan = planCommitMessageGeneration(result.value.params, 'Write Git text')
+        expect(plan.ok).toBe(true)
+        if (!plan.ok) {
+          throw new Error(plan.error)
+        }
+        expect(plan.plan.args).toEqual(['--print=Write Git text', '--sandbox'])
+        expect(plan.plan.stdinPayload).toBeNull()
+      })
+    }
+  }
+
+  it('lets explicit recipe arguments override the discovered model and requested effort once', () => {
+    const result = planCommitMessageGeneration(
+      {
+        agentId: 'antigravity',
+        model: 'gemini-3.8-flash-medium',
+        thinkingLevel: 'medium',
+        agentArgs: '--model gemini-3.7-flash-low --effort low'
+      },
+      'Write Git text'
+    )
+    expect(result.ok).toBe(true)
+    if (!result.ok) {
+      throw new Error(result.error)
+    }
+    expect(result.plan.args.filter((arg) => arg === '--model')).toHaveLength(1)
+    expect(result.plan.args.filter((arg) => arg === '--effort')).toHaveLength(1)
+    expect(result.plan.args).not.toContain('gemini-3.8-flash-medium')
+    expect(result.plan.args).not.toContain('medium')
+    expect(result.plan.args).toContain('gemini-3.7-flash-low')
+    expect(result.plan.args).toContain('low')
+  })
+})

src/shared/commit-message-agent-spec.test.ts

@@ -653,8 +653,41 @@ describe('buildArgs (Antigravity)', () => {
     expect(spec.modelDiscovery?.args).toEqual(['models'])
   })
 
-  it('uses Gemini 3.5 Flash (Medium) as default model', () => {
-    expect(COMMIT_MESSAGE_AGENT_SPECS.antigravity?.defaultModelId).toBe('Gemini 3.5 Flash (Medium)')
+  it('uses the configured CLI model instead of a bundled model that can retire', () => {
+    expect(spec.defaultModelId).toBe('default')
+    expect(
+      spec.buildArgs({ prompt: 'Generate a commit message', model: spec.defaultModelId })
+    ).toEqual(['--print=Generate a commit message', '--sandbox'])
+  })
+
+  it('passes only a nonempty requested effort', () => {
+    expect(spec.buildArgs({ prompt: 'P', model: 'default', thinkingLevel: '' })).not.toContain(
+      '--effort'
+    )
+    expect(spec.buildArgs({ prompt: 'P', model: 'default', thinkingLevel: 'high' })).toEqual([
+      '--print=P',
+      '--sandbox',
+      '--effort',
+      'high'
+    ])
+  })
+
+  it('parses current tab-separated IDs without treating progress text as a model', () => {
+    expect(
+      parseAntigravityModels(
+        [
+          'Fetching available models...',
+          'id\tLabel',
+          'gemini-3.8-flash-medium\tGemini 3.8 Flash (Medium)',
+          'claude-sonnet-4-6\tClaude Sonnet 4.6 (Thinking)',
+          'gemini-3.8-flash-medium\tGemini 3.8 Flash (Medium)',
+          ''
+        ].join('\r\n')
+      )
+    ).toEqual([
+      { id: 'gemini-3.8-flash-medium', label: 'Gemini 3.8 Flash (Medium)' },
+      { id: 'claude-sonnet-4-6', label: 'Claude Sonnet 4.6 (Thinking)' }
+    ])
   })
 })
 

src/shared/commit-message-agent-specs-secondary.ts

@@ -216,15 +216,17 @@ export function buildSecondaryCommitMessageAgentSpecs({
       // using `--print=<value>` so a leading-dash prompt binds to the flag instead of
       // being parsed as its own option, and --sandbox/--model stay separate options.
       promptDelivery: 'argv',
-      buildArgs: ({ prompt, model }) => [`--print=${prompt}`, '--sandbox', '--model', model],
+      buildArgs: ({ prompt, model, thinkingLevel }) => [
+        `--print=${prompt}`,
+        '--sandbox',
+        ...(model && model !== 'default' ? ['--model', model] : []),
+        ...(thinkingLevel ? ['--effort', thinkingLevel] : [])
+      ],
+      singletonOptions: [['--model'], ['--effort']],
       modelSource: 'dynamic',
       modelDiscovery: { binary: 'agy', args: ['models'], parse: parseAntigravityModels },
-      models: [
-        { id: 'Gemini 3.5 Flash (Medium)', label: 'Gemini 3.5 Flash (Medium)' },
-        { id: 'Gemini 3.5 Flash (High)', label: 'Gemini 3.5 Flash (High)' },
-        { id: 'Gemini 3.5 Flash (Low)', label: 'Gemini 3.5 Flash (Low)' }
-      ],
-      defaultModelId: 'Gemini 3.5 Flash (Medium)'
+      models: [{ id: 'default', label: 'Config default' }],
+      defaultModelId: 'default'
     }
   }
 }

src/shared/commit-message-model-parsers.ts

@@ -235,13 +235,22 @@ export function parseCursorModels(stdout: string): CommitMessageModel[] {
 export function parseAntigravityModels(stdout: string): CommitMessageModel[] {
   const models: CommitMessageModel[] = []
   for (const rawLine of iterateModelOutputLines(stdout)) {
-    const id = rawLine.trim()
-    if (id.length === 0) {
+    const line = rawLine.trim()
+    const separator = line.indexOf('\t')
+    const id = (separator === -1 ? line : line.slice(0, separator)).trim()
+    const label = separator === -1 ? id : line.slice(separator + 1).trim()
+    // Older agy versions list display names; current versions emit id<TAB>label.
+    if (
+      !id ||
+      !label ||
+      (separator === -1 && !/^.+ \((?:low|medium|high|thinking)\)$/i.test(id)) ||
+      (separator !== -1 && (/\s/.test(id) || /^(?:id|model)$/i.test(id)))
+    ) {
       continue
     }
     models.push({
       id,
-      label: id
+      label
     })
   }
   return uniqueModels(models)

src/shared/protocol-version.ts

@@ -292,7 +292,11 @@ export const ELECTRON_REMOTE_RUNTIME_CLIENT_CAPABILITIES = [
   SESSION_TABS_RETIREMENT_PROOF_DELTA_RUNTIME_CAPABILITY
 ] as const
 
+export const ANTIGRAVITY_CONFIGURED_MODEL_RUNTIME_CAPABILITY =
+  'git.antigravity-configured-model.v1' as const
+
 export const RUNTIME_CAPABILITIES = [
+  ANTIGRAVITY_CONFIGURED_MODEL_RUNTIME_CAPABILITY,
   'files.pathsExist',
   'runtime.status.compat.v1',
   'runtime.environments.v1',

src/shared/rpc-contract/git-params.ts

@@ -1,5 +1,6 @@
 import { z } from 'zod'
 import { OptionalGitAdmissionTier } from './git-admission-tier-params'
+import { OptionalTuiAgent } from './worktree-params'
 
 export const WorktreeSelector = z.object({
   worktree: z
@@ -183,6 +184,7 @@ export const GitGenerateCommitMessage = WorktreeSelector.extend({
   sourceControlAi: SourceControlAiSettings.optional(),
   sourceControlAiResolvedParams: ResolvedSourceControlAiGenerationParams.optional(),
   agentCmdOverrides: z.record(z.string(), z.string()).optional(),
+  defaultTuiAgent: OptionalTuiAgent.nullable(),
   commitMessageDiscoveryHostKey: z.string().optional()
 })