coder(providers): v2.3 provider-lifecycle phase 3 — generic ACP dispatch

ACP dispatch now spawns from the resolved registry's launch spec instead of a hardcoded per-name switch. acp-spawn.ts gains resolveLaunchSpec(resolved, installPath): launchCommand (config override / custom-ACP command) wins, else the kept resolveAcpSpawnArgs switch is the built-in fallback. acp-dispatch.ts spawns spec.binary/spec.args with env { ...process.env, ...spec.env }; dispatcher.ts loads the resolved def by task.agent and passes it through. Config-defined custom ACP providers dispatch with no new switch case. Built-in dispatch (opencode/goose/qwen) is byte-identical to pre-v2.3 — proven by a regression test (opencode->['acp'], goose->['acp'], qwen->['--acp'], binary=installPath ?? id, empty env -> plain process.env). Deliberate deviation from design's !installPath->null: the installPath ?? id fallback is preserved. setSessionMode/permission/streaming and the dispatcher poll/NOTIFY/running-guard untouched. 7 new acp-spawn.test.ts cases. No routes/UI (Phase 4+).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/coder/src/services/__tests__/acp-spawn.test.ts

@@ -0,0 +1,73 @@
+import { describe, it, expect } from 'vitest';
+import { resolveLaunchSpec, resolveAcpSpawnArgs } from '../acp-spawn.js';
+import { buildResolvedRegistry } from '../provider-config-registry.js';
+import type { CoderProvidersFile } from '../provider-config.js';
+import { PROVIDERS } from '../provider-registry.js';
+
+/** Resolved def for a provider id under the given config (default: no override). */
+function builtin(name: string, providers: CoderProvidersFile['providers'] = {}) {
+  const def = buildResolvedRegistry(PROVIDERS, { providers }).get(name);
+  if (!def) throw new Error(`no resolved def for ${name}`);
+  return def;
+}
+
+describe('resolveLaunchSpec', () => {
+  // --- byte-identical built-in regression (the HARD CONSTRAINT) ---------------
+  // These argv values are the pre-v2.3 resolveAcpSpawnArgs switch outputs and
+  // MUST NOT change. spawn() is `spawn(spec.binary, spec.args, ...)`, so argv
+  // parity here is dispatch parity.
+  it('opencode (no override) → byte-identical argv ["acp"], binary = installPath', () => {
+    const spec = resolveLaunchSpec(builtin('opencode'), '/usr/bin/opencode');
+    expect(spec).not.toBeNull();
+    expect(spec!.args).toEqual(['acp']); // pre-v2.3 value
+    expect(spec!.binary).toBe('/usr/bin/opencode');
+    expect(spec!.env).toBeUndefined();
+    // cross-check against the switch source-of-truth
+    expect(spec!.args).toEqual(resolveAcpSpawnArgs('opencode'));
+  });
+
+  it('goose → ["acp"], qwen → ["--acp"] (byte-identical)', () => {
+    expect(resolveLaunchSpec(builtin('goose'), '/usr/bin/goose')!.args).toEqual(['acp']);
+    expect(resolveLaunchSpec(builtin('qwen'), '/usr/bin/qwen')!.args).toEqual(['--acp']);
+  });
+
+  it('built-in with null installPath falls back to the bare id (pre-v2.3 `installPath ?? agent`)', () => {
+    const spec = resolveLaunchSpec(builtin('opencode'), null);
+    expect(spec!.binary).toBe('opencode');
+    expect(spec!.args).toEqual(['acp']);
+  });
+
+  it('non-ACP / unknown provider → null (claude has no ACP argv)', () => {
+    expect(resolveLaunchSpec(builtin('claude'), '/usr/bin/claude')).toBeNull();
+    expect(resolveLaunchSpec(builtin('boocode'), null)).toBeNull();
+  });
+
+  // --- config-driven launch (the new capability) ------------------------------
+  it('custom ACP entry → configured command + env reach the spec', () => {
+    const def = builtin('amp-acp', {
+      'amp-acp': { extends: 'acp', label: 'Amp', command: ['amp-acp', '--acp'], env: { AMP_KEY: 'x' } },
+    });
+    const spec = resolveLaunchSpec(def, '/usr/local/bin/amp-acp');
+    expect(spec).not.toBeNull();
+    expect(spec!.binary).toBe('amp-acp'); // command[0], not the resolved install path
+    expect(spec!.args).toEqual(['--acp']); // command.slice(1)
+    expect(spec!.env).toEqual({ AMP_KEY: 'x' });
+  });
+
+  it('built-in WITH a config command override uses the override, not the switch default', () => {
+    const def = builtin('opencode', { opencode: { command: ['opencode', 'acp', '--verbose'], env: { DEBUG: '1' } } });
+    const spec = resolveLaunchSpec(def, '/usr/bin/opencode');
+    expect(spec!.binary).toBe('opencode');
+    expect(spec!.args).toEqual(['acp', '--verbose']);
+    expect(spec!.env).toEqual({ DEBUG: '1' });
+  });
+});
+
+describe('acp-dispatch spawn wiring (documented pass-through)', () => {
+  // dispatchViaAcp spawns `spawn(spec.binary, spec.args, { env: { ...process.env, ...spec.env } })`.
+  // The env merge layers config env over process.env; for a built-in with no
+  // config env, spec.env is undefined → { ...process.env } (byte-identical).
+  it('built-in with no config env yields an undefined spec.env (→ plain process.env at spawn)', () => {
+    expect(resolveLaunchSpec(builtin('opencode'), '/usr/bin/opencode')!.env).toBeUndefined();
+  });
+});

apps/coder/src/services/acp-dispatch.ts

@@ -26,7 +26,8 @@ import type { Broker } from '@boocode/server/broker';
 import type { WsFrame } from '@boocode/server/ws-frames';
 import { spawn } from 'node:child_process';
 import { findThoughtLevelConfigId } from './acp-derive.js';
-import { resolveAcpSpawnArgs } from './acp-spawn.js';
+import { resolveLaunchSpec } from './acp-spawn.js';
+import { getResolvedRegistry, type ResolvedProviderDef } from './provider-config-registry.js';
 import { createAcpNdJsonStream } from './acp-stream.js';
 import { waitForPermissionResponse, waitForElicitationResponse, cancelPendingPermission } from './permission-waiter.js';
 import { mergeTaskCommands, getTaskCommands } from './agent-commands-cache.js';
@@ -59,6 +60,9 @@ export interface AcpDispatchOpts {
   messageId?: string;
   broker?: Broker;
   installPath?: string;
+  /** v2.3 phase 3: resolved registry def for launch-spec resolution. The
+   *  dispatcher loads this by task.agent; falls back to a registry lookup here. */
+  resolved?: ResolvedProviderDef;
   signal?: AbortSignal;
   log: FastifyBaseLogger;
 }
@@ -282,8 +286,12 @@ export async function dispatchViaAcp(opts: AcpDispatchOpts): Promise<AcpDispatch
     broker,
   } = opts;
 
-  const args = resolveAcpSpawnArgs(agent);
-  if (!args) {
+  // v2.3 phase 3: launch from the resolved registry def (config override /
+  // custom-ACP command) with the built-in switch as the fallback. The dispatcher
+  // passes `resolved`; fall back to a registry lookup if it didn't.
+  const resolved = opts.resolved ?? getResolvedRegistry().get(agent);
+  const spec = resolved ? resolveLaunchSpec(resolved, installPath ?? null) : null;
+  if (!spec) {
     return {
       exitCode: 1,
       output: `Agent '${agent}' does not support ACP.`,
@@ -293,12 +301,11 @@ export async function dispatchViaAcp(opts: AcpDispatchOpts): Promise<AcpDispatch
     };
   }
 
-  const binary = installPath ?? agent;
-  log.info({ agent, binary, worktreePath, modeId, model: opts.model }, 'acp-dispatch: spawning');
-  const child = spawn(binary, args, {
+  log.info({ agent, binary: spec.binary, worktreePath, modeId, model: opts.model }, 'acp-dispatch: spawning');
+  const child = spawn(spec.binary, spec.args, {
     cwd: worktreePath,
     stdio: ['pipe', 'pipe', 'pipe'],
-    env: { ...process.env },
+    env: { ...process.env, ...spec.env },
   });
 
   const streamCtx = new AcpStreamContext(

apps/coder/src/services/acp-spawn.ts

@@ -1,5 +1,9 @@
+import type { ResolvedProviderDef } from './provider-config-registry.js';
+
 /**
- * Resolve ACP spawn argv per provider (host-probe verified 2026-05-25).
+ * Resolve ACP spawn argv per built-in provider (host-probe verified 2026-05-25).
+ * Source of truth for built-in default argv — resolveLaunchSpec wraps these; it
+ * does NOT replace them.
  */
 export function resolveAcpSpawnArgs(agent: string): string[] | null {
   switch (agent) {
@@ -13,6 +17,34 @@ export function resolveAcpSpawnArgs(agent: string): string[] | null {
   }
 }
 
+/**
+ * v2.3 phase 3: resolve the launch spec for an ACP dispatch (design.md §5.1).
+ * Consults the resolved registry's launchCommand (config override or custom-ACP
+ * entry) first; otherwise falls back to the built-in default argv above.
+ *
+ * Byte-identical to pre-v2.3 for built-ins with no override: binary is
+ * `installPath ?? id` and args come from resolveAcpSpawnArgs — exactly the
+ * `binary = installPath ?? agent` + `resolveAcpSpawnArgs(agent)` the dispatcher
+ * used before. (Deliberate deviation from design §5.1's `!installPath → null`:
+ * the old path spawned the bare agent name when install_path was missing, so we
+ * preserve the `?? id` fallback rather than fail.)
+ */
+export function resolveLaunchSpec(
+  resolved: ResolvedProviderDef,
+  installPath: string | null,
+): { binary: string; args: string[]; env?: Record<string, string> } | null {
+  if (resolved.launchCommand) {
+    return {
+      binary: resolved.launchCommand[0],
+      args: resolved.launchCommand.slice(1),
+      env: resolved.env,
+    };
+  }
+  const args = resolveAcpSpawnArgs(resolved.id);
+  if (!args) return null;
+  return { binary: installPath ?? resolved.id, args, env: resolved.env };
+}
+
 export function resolveAcpProbeBinaries(agent: string): string[] {
   return [agent];
 }

apps/coder/src/services/dispatcher.ts

@@ -5,6 +5,7 @@ import type { WsFrame } from '@boocode/server/ws-frames';
 import type { Config } from '../config.js';
 import { createWorktree, diffWorktree, cleanupWorktree } from './worktrees.js';
 import { dispatchViaAcp } from './acp-dispatch.js';
+import { getResolvedRegistry } from './provider-config-registry.js';
 import { dispatchViaPty } from './pty-dispatch.js';
 import { clearTaskCommands, setTaskCommands } from './agent-commands-cache.js';
 import { getManifestCommands } from './provider-commands.js';
@@ -340,6 +341,7 @@ export function createDispatcher(deps: Deps): { start(): void; stop(): Promise<v
       if (supportsAcp) {
         const result = await dispatchViaAcp({
           agent,
+          resolved: getResolvedRegistry().get(agent),
           task: task.input,
           worktreePath,
           installPath: installPath ?? undefined,