feat(orchestration): support OpenCode worker model selection

docs/site/content/docs/cli/orchestration.mdx

@@ -44,7 +44,7 @@ orca orchestration worker-start --task <taskId> --worktree new-child --name bill
 orca orchestration worker-start --task <taskId> --worktree current --agent claude --model <opaque-model-id> --effort high --json
 ```
 
-`--model` accepts opaque provider model IDs for Claude, Codex, and Cursor. `--effort` requires `--model` and only applies when that agent/model supports the level. Neither flag can combine with `--terminal` (reuse an existing pane). Overrides apply to that launch only and show under `launch.requested` / `launch.effective` in the start receipt. Federated starts need a worker host that advertises launch-preference support.
+`--model` accepts opaque provider model IDs for Claude, Codex, Cursor, Antigravity, and OpenCode. `--effort` requires `--model` and only applies when that agent/model supports the level. Neither flag can combine with `--terminal` (reuse an existing pane). Overrides apply to that launch only and show under `launch.requested` / `launch.effective` in the start receipt. Federated starts need a worker host that advertises launch-preference support.
 
 Wait for completions (process every message in a Delivery, then ack):
 

skill-guides/orchestration/references/coordinator-loop.md

@@ -21,7 +21,7 @@ when an older CLI rejects the flag. A nested worker must respect
 
 ## Launch preferences
 
-For a fresh Claude, Codex, Cursor, or Antigravity terminal, `--model` accepts an opaque
+For a fresh Claude, Codex, Cursor, Antigravity, or OpenCode terminal, `--model` accepts an opaque
 provider model ID. Pass it only when the user named a model; otherwise omit it
 so the worker inherits the user's configured agent default. Add `--effort` only
 when that model supports it:

src/cli/specs/orchestration-worker-specs.ts

@@ -34,7 +34,7 @@ export const ORCHESTRATION_WORKER_COMMAND_SPECS: CommandSpec[] = [
     notes: [
       'Current and existing worktrees never rerun setup; a fresh agent terminal is created unless --terminal is explicit.',
       'When reusing --terminal, pass --worktree for that terminal; current means the coordinator worktree.',
-      '--model supports Claude, Codex, Cursor, and Antigravity opaque provider model ids; --effort requires --model. Neither can combine with --terminal.',
+      '--model supports Claude, Codex, Cursor, Antigravity, and OpenCode opaque provider model ids; --effort requires --model. Neither can combine with --terminal.',
       'New worktrees use agent-first creation and default --setup to run. Repository start-immediately runs setup beside the agent; wait-for-setup gates agent readiness and task input.',
       'Creation flags (--name, --repo, --base-branch, --display-name, --comment, --setup) are rejected for current/existing worktrees. Use exact --repo on the selected server; project/host convenience routing remains on worktree create.',
       "How the worker runs follows the user's own setting for new agent tabs; there is no flag for it and no caller needs to ask. A dispatch the setting cannot apply to still starts, so the placement, agent, and launch options passed here are always the ones honoured.",

src/main/runtime/rpc/methods/orchestration/worker/worker-launch-preferences.test.ts

@@ -67,6 +67,29 @@ describe('orchestration worker launch preferences', () => {
     ).toEqual({ model: 'gpt-5.6-sol' })
   })
 
+  it('passes an opaque OpenCode model through the launch catalog', () => {
+    expect(
+      resolveWorkerLaunchPreferences({
+        agent: 'opencode',
+        model: 'zai-coding-plan/glm-5.3-flash'
+      })
+    ).toEqual({
+      preferences: { model: 'zai-coding-plan/glm-5.3-flash' },
+      receipt: {
+        requested: {
+          agent: 'opencode',
+          model: 'zai-coding-plan/glm-5.3-flash',
+          effort: null
+        },
+        effective: {
+          agent: 'opencode',
+          model: 'zai-coding-plan/glm-5.3-flash',
+          effort: null
+        }
+      }
+    })
+  })
+
   it.each([
     {
       model: 'gpt-5.6-sol',
@@ -138,6 +161,16 @@ describe('orchestration worker launch preferences', () => {
     }
   })
 
+  it('rejects unsupported OpenCode effort instead of silently dropping it', () => {
+    expect(() =>
+      resolveWorkerLaunchPreferences({
+        agent: 'opencode',
+        model: 'zai-coding-plan/glm-5.3-flash',
+        effort: 'high'
+      })
+    ).toThrow('Agent opencode model zai-coding-plan/glm-5.3-flash does not support effort high.')
+  })
+
   it('rejects effort without a model', () => {
     expect(() => resolveWorkerLaunchPreferences({ agent: 'codex', effort: 'high' })).toThrow(
       '--effort requires --model'

src/main/runtime/rpc/methods/orchestration/worker/worker-launch-preferences.ts

@@ -1,10 +1,12 @@
 import type { AgentLaunchPreferences } from '../../../../../../shared/agent-session-host-authority'
 import {
   findCatalogModel,
-  findCatalogOption,
-  getAgentSessionOptionCatalog
+  findCatalogOption
 } from '../../../../../../shared/agent-session-option-catalog'
-import { resolveAgentSessionOptionLaunch } from '../../../../../../shared/agent-session-option-launch'
+import {
+  getAgentSessionOptionLaunchCatalog,
+  resolveAgentSessionOptionLaunch
+} from '../../../../../../shared/agent-session-option-launch'
 import { ORCHESTRATION_WORKER_LAUNCH_PREFERENCES_RUNTIME_CAPABILITY } from '../../../../../../shared/protocol-version'
 import type { TuiAgent } from '../../../../../../shared/tui-agent'
 import { OrchestrationError } from '../../../../orchestration/orchestration-error'
@@ -66,7 +68,7 @@ export function resolveWorkerLaunchPreferences(args: {
     }
   }
 
-  const catalog = getAgentSessionOptionCatalog(args.agent)
+  const catalog = getAgentSessionOptionLaunchCatalog(args.agent)
   if (!catalog?.supportsWorkerLaunchPreferences || !catalog.modelApply.launchArgs) {
     throw new OrchestrationError(
       'invalid_argument',

src/shared/agent-session-option-catalog-opencode.test.ts

@@ -0,0 +1,34 @@
+import { describe, expect, it } from 'vitest'
+import { getAgentSessionOptionCatalog } from './agent-session-option-catalog'
+import {
+  removeOverriddenAgentSessionArgs,
+  resolveAgentSessionOptionLaunch
+} from './agent-session-option-launch'
+
+describe('OpenCode launch options', () => {
+  it('does not expose worker-only launch options as an interactive session catalog', () => {
+    expect(getAgentSessionOptionCatalog('opencode')).toBeNull()
+  })
+
+  it('maps an opaque model id to the OpenCode --model flag', () => {
+    expect(
+      resolveAgentSessionOptionLaunch('opencode', {
+        model: 'zai-coding-plan/glm-5.3-flash'
+      })
+    ).toEqual({
+      args: ['--model', 'zai-coding-plan/glm-5.3-flash'],
+      appliedValues: { model: 'zai-coding-plan/glm-5.3-flash' }
+    })
+  })
+
+  it('removes a configured model flag before applying a per-launch model', () => {
+    expect(
+      removeOverriddenAgentSessionArgs('opencode', { model: 'zai-coding-plan/glm-5.3-flash' }, [
+        '--model',
+        'opencode/global-default',
+        '--log-level',
+        'DEBUG'
+      ])
+    ).toEqual(['--log-level', 'DEBUG'])
+  })
+})

src/shared/agent-session-option-catalog-opencode.ts

@@ -0,0 +1,16 @@
+import { hasFlag } from './agent-cli-flag-detection'
+import { removeAgentArgOption } from './agent-session-option-agent-args'
+import type { AgentSessionOptionCatalog } from './agent-session-option-catalog-types'
+
+const MODEL_FLAGS = ['-m', '--model'] as const
+
+// Why: worker-start needs launch serialization without exposing a new Native Chat option surface.
+export const OPENCODE_LAUNCH_OPTION_CATALOG: AgentSessionOptionCatalog = {
+  supportsWorkerLaunchPreferences: true,
+  models: [],
+  modelApply: {
+    launchArgs: (value) => ['--model', String(value)],
+    agentArgsOverride: (tokens) => hasFlag(tokens, MODEL_FLAGS),
+    removeAgentArgs: (tokens) => removeAgentArgOption(tokens, MODEL_FLAGS)
+  }
+}

src/shared/agent-session-option-launch.ts

@@ -1,18 +1,26 @@
 import type { AgentType } from './agent-status-types'
 import { findCatalogModel, getAgentSessionOptionCatalog } from './agent-session-option-catalog'
+import { OPENCODE_LAUNCH_OPTION_CATALOG } from './agent-session-option-catalog-opencode'
+import type { AgentSessionOptionCatalog } from './agent-session-option-catalog-types'
 import type { SessionOptionValue } from './native-chat-session-options'
 
 export type ResolvedSessionOptionLaunch = {
   args: string[]
   appliedValues: Record<string, SessionOptionValue>
 }
 
+export function getAgentSessionOptionLaunchCatalog(
+  agent: AgentType
+): AgentSessionOptionCatalog | null {
+  return agent === 'opencode' ? OPENCODE_LAUNCH_OPTION_CATALOG : getAgentSessionOptionCatalog(agent)
+}
+
 export function removeOverriddenAgentSessionArgs(
   agent: AgentType,
   values: Record<string, SessionOptionValue> | null | undefined,
   tokens: readonly string[]
 ): string[] {
-  const catalog = getAgentSessionOptionCatalog(agent)
+  const catalog = getAgentSessionOptionLaunchCatalog(agent)
   const modelId = typeof values?.model === 'string' ? values.model : null
   if (!catalog || !values || !modelId) {
     return [...tokens]
@@ -34,7 +42,7 @@ export function resolveAgentSessionOptionLaunch(
   trailingAgentArgs: readonly string[] = [],
   includeCatalogDefaults = true
 ): ResolvedSessionOptionLaunch {
-  const catalog = getAgentSessionOptionCatalog(agent)
+  const catalog = getAgentSessionOptionLaunchCatalog(agent)
   const modelId = typeof values?.model === 'string' ? values.model : null
   if (!catalog || !values || !modelId) {
     return { args: [], appliedValues: {} }

src/shared/tui-agent-startup-session-options.test.ts

@@ -72,6 +72,24 @@ describe('tui agent startup session options', () => {
     expect(plan?.sessionOptions).toEqual({ model: 'gemini-3.1-pro-high', effort: 'high' })
   })
 
+  it('keeps OpenCode agent arguments while replacing only the per-launch model', () => {
+    const plan = buildAgentStartupPlan({
+      agent: 'opencode',
+      prompt: '',
+      cmdOverrides: {},
+      platform: 'linux',
+      allowEmptyPromptLaunch: true,
+      sessionOptions: { model: 'zai-coding-plan/glm-5.3-flash' },
+      sessionOptionsOverrideAgentArgs: true,
+      agentArgs: '--share --model opencode/global-default'
+    })
+    expect(plan?.launchCommand).toBe("opencode '--share' '--model' 'zai-coding-plan/glm-5.3-flash'")
+    expect(plan?.launchConfig.agentCommand).toBe(
+      "opencode '--share' '--model' 'opencode/global-default'"
+    )
+    expect(plan?.sessionOptions).toEqual({ model: 'zai-coding-plan/glm-5.3-flash' })
+  })
+
   it('inserts worker preferences before an argument terminator', () => {
     const plan = buildAgentStartupPlan({
       agent: 'codex',