chat: point OpenCode at a fixed pm2-managed server (fixes empty model picker)

The per-cwd `opencode serve` spawning is replaced by a single fixed server
(http://127.0.0.1:4096, OPENCODE_SERVER_URL) managed by pm2 — added as
`officer-opencode` in ecosystem.config.cjs (cwd = home).

Root-cause fix for the empty model selector: list-models shelled out to
`opencode models`, which failed at runtime on the deployed server (the picker got
only Claude tiers). It now reads the fixed server's GET /config/providers over HTTP —
11ms and reliable — so the curated OpenCode models (Big Pickle, Claude Haiku) show up.

- server-manager.ts — drops spawning; exposes OPENCODE_SERVER_URL + a health check.
- client.ts — createSession no longer binds a directory (sessions live in the one
  server's project).
- send-opencode.ts / opencode-sessions.ts / chat.ts — use the fixed server; drop the
  cwd/home plumbing. Session list/load/delete/rename now hit :4096.

Verified end-to-end against the live server: model list, streaming turn, session
list, and transcript load all work with no spawning.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/servers/api/chat/chat.ts

@@ -18,7 +18,6 @@ import {
 } from './opencode-sessions';
 import { listChatModels } from './list-models';
 import { logger } from './logger';
-import { getHomeDirForRole } from '../../data-path';
 import { readSttConfig } from '../server-settings/stt';
 import { transcribeAudio } from '../stt/transcribe';
 
@@ -26,11 +25,9 @@ export const chatRouter = createRouter();
 
 // The working directory a request operates on: an explicit ?cwd= (a chosen pwd), else the default
 // claude_sessions dir. Claude groups sessions by cwd, so this selects which project group we read.
+// (OpenCode sessions all live in the one fixed server and ignore cwd.)
 const cwdOf = (ctx: Context, email: string): string => ctx.req.query('cwd')?.trim() || getClaudeSessionsCwd(email);
 
-// The home dir an OpenCode `serve` runs under (so it reads the user's ~/.local/share/opencode auth).
-const homeOf = (ctx: Context): string => getHomeDirForRole(ctx.get('user').email, ctx.get('user').role);
-
 // GET /chat/pwds — the default /chat dir plus every directory that already has Claude sessions.
 chatRouter.get('/pwds', (ctx) => {
   const email = ctx.get('user').email;
@@ -43,7 +40,7 @@ chatRouter.get('/sessions', async (ctx) => {
   const email = ctx.get('user').email;
   const cwd = cwdOf(ctx, email);
   const claude = listClaudeSessions(email, cwd).map((s) => ({ ...s, harness: 'claude' as const }));
-  const opencode = await listOpenCodeSessions(cwd, homeOf(ctx));
+  const opencode = await listOpenCodeSessions();
   const sessions = [...claude, ...opencode].sort((a, b) => b.updatedAt.localeCompare(a.updatedAt));
   return ctx.json({ sessions });
 });
@@ -53,9 +50,7 @@ chatRouter.get('/sessions/:id', async (ctx) => {
   const email = ctx.get('user').email;
   const id = ctx.req.param('id');
   const cwd = cwdOf(ctx, email);
-  const detail = isOpenCodeSessionId(id)
-    ? await loadOpenCodeSession(cwd, homeOf(ctx), id)
-    : loadClaudeSession(email, cwd, id);
+  const detail = isOpenCodeSessionId(id) ? await loadOpenCodeSession(id) : loadClaudeSession(email, cwd, id);
   if (!detail) return ctx.text('Not found', 404);
   return ctx.json(detail);
 });
@@ -65,9 +60,7 @@ chatRouter.delete('/sessions/:id', async (ctx) => {
   const email = ctx.get('user').email;
   const id = ctx.req.param('id');
   const cwd = cwdOf(ctx, email);
-  const ok = isOpenCodeSessionId(id)
-    ? await deleteOpenCodeSession(cwd, homeOf(ctx), id)
-    : deleteClaudeSession(email, cwd, id);
+  const ok = isOpenCodeSessionId(id) ? await deleteOpenCodeSession(id) : deleteClaudeSession(email, cwd, id);
   if (!ok) return ctx.text('Not found', 404);
   return ctx.json({ ok: true });
 });
@@ -80,7 +73,7 @@ chatRouter.patch('/sessions/:id/title', async (ctx) => {
   const { title } = await ctx.req.json<{ title?: string }>();
   if (!title?.trim()) return ctx.text('title is required', 400);
   const ok = isOpenCodeSessionId(id)
-    ? await renameOpenCodeSession(cwd, homeOf(ctx), id, title.trim())
+    ? await renameOpenCodeSession(id, title.trim())
     : renameClaudeSession(email, cwd, id, title.trim());
   if (!ok) return ctx.text('Not found', 404);
   return ctx.json({ ok: true });

src/servers/api/chat/list-models.ts

@@ -1,6 +1,5 @@
 import type { ModelInfo } from './types';
-import { homedir } from 'os';
-import { join } from 'path';
+import { OPENCODE_SERVER_URL } from './opencode/server-manager';
 
 // The Claude harness runs the `claude` CLI, so its tiers are a fixed set.
 const CLAUDE_CODE_MODELS: ModelInfo[] = [
@@ -9,46 +8,47 @@ const CLAUDE_CODE_MODELS: ModelInfo[] = [
   { id: 'claude-code/haiku', name: 'haiku', provider: 'claude-code', contextWindow: 200000, maxTokens: 8192, reasoning: false, images: true },
 ];
 
-const OPENCODE_BIN = process.env.OPENCODE_BIN || join(homedir(), '.opencode', 'bin', 'opencode');
-
-// Curated OpenCode models to surface in the picker (the full `opencode models` catalog is ~58 entries).
+// Curated OpenCode models to surface in the picker (the full catalog is ~58 entries).
 const OPENCODE_ALLOWLIST = new Set(['opencode/big-pickle', 'opencode/claude-haiku-4-5']);
 
-// Cache the OpenCode catalog; it's stable for a session and `opencode models` costs a subprocess.
+// Cache the OpenCode catalog; it's stable for a session.
 let openCodeCache: ModelInfo[] | null = null;
 
 export function invalidateModelCache(): void {
   openCodeCache = null;
 }
 
-// Enumerate OpenCode models via `opencode models` (ids are `providerID/modelID`, e.g.
-// `opencode/claude-opus-4-8`). Metadata (context/tokens/modalities) is left at neutral defaults for
-// now — it can be enriched later from a serve's GET /config/providers.
+type ProvidersResponse = {
+  providers?: Array<{ id?: string; models?: Record<string, unknown> }>;
+};
+
+// Enumerate OpenCode models from the fixed server's GET /config/providers (reliable — no subprocess).
+// Model ids are `providerID/modelID` (e.g. `opencode/claude-haiku-4-5`); metadata is left at neutral
+// defaults for now.
 async function listOpenCodeModels(): Promise<ModelInfo[]> {
   if (openCodeCache) return openCodeCache;
   try {
-    const proc = Bun.spawn([OPENCODE_BIN, 'models'], { stdout: 'pipe', stderr: 'ignore' });
-    const out = await new Response(proc.stdout).text();
-    await proc.exited;
+    const res = await fetch(`${OPENCODE_SERVER_URL}/config/providers`, { signal: AbortSignal.timeout(5000) });
+    if (!res.ok) return [];
+    const data = (await res.json()) as ProvidersResponse;
 
-    const models: ModelInfo[] = out
-      // eslint-disable-next-line no-control-regex
-      .replace(/\x1b\[[0-9;]*m/g, '')
-      .split('\n')
-      .map((line) => line.trim())
-      .filter((line) => OPENCODE_ALLOWLIST.has(line))
-      .map((full) => {
-        const slash = full.indexOf('/');
-        return {
+    const models: ModelInfo[] = [];
+    for (const provider of data.providers ?? []) {
+      const providerId = provider.id ?? '';
+      for (const modelId of Object.keys(provider.models ?? {})) {
+        const full = `${providerId}/${modelId}`;
+        if (!OPENCODE_ALLOWLIST.has(full)) continue;
+        models.push({
           id: full,
-          name: full.slice(slash + 1),
-          provider: full.slice(0, slash),
+          name: modelId,
+          provider: providerId,
           contextWindow: 200000,
           maxTokens: 8192,
           reasoning: false,
           images: true,
-        } satisfies ModelInfo;
-      });
+        });
+      }
+    }
 
     openCodeCache = models;
     return models;

src/servers/api/chat/opencode-sessions.ts

@@ -3,15 +3,15 @@ import { ensureServer } from './opencode/server-manager';
 import { getConnection } from './opencode/client';
 import { logger } from './logger';
 
-// The OpenCode analog of claude-sessions.ts. OpenCode's own SQLite store is the source of truth, read
-// via its HTTP API (never the DB directly). A `serve` is directory-scoped, so listing sessions for a
-// cwd just means asking the serve rooted at that cwd. Returns the same shapes as the Claude reader,
+// The OpenCode analog of claude-sessions.ts. OpenCode's own store is the source of truth, read via the
+// fixed pm2-managed server's HTTP API (never the DB directly). All OpenCode /chat sessions live in that
+// one server's project, so listing is just GET /session. Returns the same shapes as the Claude reader,
 // tagged harness:'opencode', so chat.ts can merge both harnesses transparently.
 
-/** List OpenCode sessions for a working directory. Never throws — returns [] if OpenCode is unavailable. */
-export async function listOpenCodeSessions(cwd: string, home: string): Promise<ClaudeSessionSummary[]> {
+/** List OpenCode sessions. Never throws — returns [] if the server is unavailable. */
+export async function listOpenCodeSessions(): Promise<ClaudeSessionSummary[]> {
   try {
-    const { baseUrl } = await ensureServer(cwd, home);
+    const { baseUrl } = await ensureServer();
     const sessions = await getConnection(baseUrl).listSessions();
     return sessions.map((s) => {
       const created = s.time?.created ?? Date.now();
@@ -19,7 +19,7 @@ export async function listOpenCodeSessions(cwd: string, home: string): Promise<C
       return {
         id: s.id,
         title: s.title || '(untitled)',
-        cwd,
+        cwd: s.location?.directory ?? '',
         createdAt: new Date(created).toISOString(),
         updatedAt: new Date(updated).toISOString(),
         messageCount: 0, // the session list endpoint doesn't include a turn count
@@ -27,15 +27,15 @@ export async function listOpenCodeSessions(cwd: string, home: string): Promise<C
       } satisfies ClaudeSessionSummary;
     });
   } catch (err) {
-    logger.warn('Failed to list OpenCode sessions', { cwd, error: String(err) });
+    logger.warn('Failed to list OpenCode sessions', { error: String(err) });
     return [];
   }
 }
 
 /** Load one OpenCode session's transcript, rebuilt into the shared display message shape. */
-export async function loadOpenCodeSession(cwd: string, home: string, sessionId: string): Promise<ClaudeSessionDetail | null> {
+export async function loadOpenCodeSession(sessionId: string): Promise<ClaudeSessionDetail | null> {
   try {
-    const { baseUrl } = await ensureServer(cwd, home);
+    const { baseUrl } = await ensureServer();
     const stored = await getConnection(baseUrl).getMessages(sessionId);
 
     const messages: ClaudeChatMessage[] = [];
@@ -70,21 +70,21 @@ export async function loadOpenCodeSession(cwd: string, home: string, sessionId:
               isError: Boolean(p.state?.error),
             });
           }
-          // text-part deltas already excluded reasoning; skip reasoning/step-* parts here too.
+          // skip reasoning/step-* parts (parity with the streaming delta filter).
         }
       }
     }
 
-    return { id: sessionId, model: modelId ? `opencode/${modelId}` : 'opencode', cwd, messages };
+    return { id: sessionId, model: modelId ? `opencode/${modelId}` : 'opencode', cwd: '', messages };
   } catch (err) {
     logger.warn('Failed to load OpenCode session', { sessionId, error: String(err) });
     return null;
   }
 }
 
-export async function deleteOpenCodeSession(cwd: string, home: string, sessionId: string): Promise<boolean> {
+export async function deleteOpenCodeSession(sessionId: string): Promise<boolean> {
   try {
-    const { baseUrl } = await ensureServer(cwd, home);
+    const { baseUrl } = await ensureServer();
     return await getConnection(baseUrl).deleteSession(sessionId);
   } catch (err) {
     logger.warn('Failed to delete OpenCode session', { sessionId, error: String(err) });
@@ -92,9 +92,9 @@ export async function deleteOpenCodeSession(cwd: string, home: string, sessionId
   }
 }
 
-export async function renameOpenCodeSession(cwd: string, home: string, sessionId: string, title: string): Promise<boolean> {
+export async function renameOpenCodeSession(sessionId: string, title: string): Promise<boolean> {
   try {
-    const { baseUrl } = await ensureServer(cwd, home);
+    const { baseUrl } = await ensureServer();
     return await getConnection(baseUrl).renameSession(sessionId, title);
   } catch (err) {
     logger.warn('Failed to rename OpenCode session', { sessionId, error: String(err) });

src/servers/api/chat/opencode/client.ts

@@ -105,8 +105,9 @@ class ServerConnection {
     return (await res.json()) as T;
   }
 
-  async createSession(directory: string, title?: string): Promise<string> {
-    const session = await this.postJson<{ id?: string }>('/session', { directory, title });
+  async createSession(title?: string): Promise<string> {
+    // No `directory` — the session lives in the fixed server's own project (its cwd).
+    const session = await this.postJson<{ id?: string }>('/session', title ? { title } : {});
     if (!session.id) throw new Error('opencode POST /session returned no id');
     return session.id;
   }

src/servers/api/chat/opencode/server-manager.ts

@@ -1,118 +1,19 @@
-import type { Subprocess } from 'bun';
-import { homedir } from 'os';
-import { join } from 'path';
-import { mkdirSync } from 'fs';
-import { logger } from '../logger';
+// The OpenCode server is a fixed, pm2-managed process (see officer-opencode in ecosystem.config.cjs)
+// listening on a known port — not spawned per-cwd by us. All OpenCode chat + session traffic goes to
+// this one server; sessions live in its project store. Override the URL with OPENCODE_SERVER_URL.
 
-// The `opencode` binary. Pinned (like CLAUDE_BIN) rather than resolved from PATH; override with
-// OPENCODE_BIN. NOTE: the installed binary is 1.17.9 — the 1.18.4 upgrade never landed on disk.
-const OPENCODE_BIN = process.env.OPENCODE_BIN || join(homedir(), '.opencode', 'bin', 'opencode');
+export const OPENCODE_SERVER_URL = process.env.OPENCODE_SERVER_URL || 'http://127.0.0.1:4096';
 
-const HEALTH_TIMEOUT_MS = 20_000;
-const HEALTH_POLL_MS = 200;
-const START_ATTEMPTS = 3;
-
-type OpenCodeServer = {
-  baseUrl: string;
-  proc: Subprocess;
-  port: number;
-};
-
-// One warm `opencode serve` per working directory (sessions bind to a directory at creation).
-const servers = new Map<string, OpenCodeServer>();
-const starting = new Map<string, Promise<OpenCodeServer>>();
-
-/** Grab an ephemeral free port by briefly binding one and releasing it. */
-function getFreePort(): number {
-  const probe = Bun.serve({ port: 0, hostname: '127.0.0.1', fetch: () => new Response('') });
-  const port = probe.port;
-  probe.stop(true);
-  if (port == null) throw new Error('failed to acquire a free port');
-  return port;
-}
-
-async function isHealthy(baseUrl: string): Promise<boolean> {
+export async function isServerHealthy(): Promise<boolean> {
   try {
-    const res = await fetch(`${baseUrl}/api/health`, { signal: AbortSignal.timeout(2000) });
+    const res = await fetch(`${OPENCODE_SERVER_URL}/api/health`, { signal: AbortSignal.timeout(3000) });
     return res.ok;
   } catch {
     return false;
   }
 }
 
-async function waitHealthy(baseUrl: string, timeoutMs: number): Promise<boolean> {
-  const deadline = Date.now() + timeoutMs;
-  while (Date.now() < deadline) {
-    if (await isHealthy(baseUrl)) return true;
-    await new Promise((r) => setTimeout(r, HEALTH_POLL_MS));
-  }
-  return false;
-}
-
-async function startServer(cwd: string, home: string): Promise<OpenCodeServer> {
-  mkdirSync(cwd, { recursive: true });
-
-  for (let attempt = 1; attempt <= START_ATTEMPTS; attempt += 1) {
-    const port = getFreePort();
-    const baseUrl = `http://127.0.0.1:${port}`;
-    // Loopback-only + no OPENCODE_SERVER_PASSWORD → the server is open on 127.0.0.1 (single-user box).
-    // HOME is set to the caller's home so `opencode` reads that user's ~/.local/share/opencode auth.
-    const proc = Bun.spawn([OPENCODE_BIN, 'serve', '--port', String(port), '--hostname', '127.0.0.1'], {
-      cwd,
-      env: { ...process.env, HOME: home },
-      stdout: 'ignore',
-      stderr: 'ignore',
-    });
-
-    if (await waitHealthy(baseUrl, HEALTH_TIMEOUT_MS)) {
-      logger.info('opencode serve started', { cwd, baseUrl });
-      proc.exited.then((code) => {
-        // Drop the cached entry on exit so the next turn respawns.
-        if (servers.get(cwd)?.proc === proc) servers.delete(cwd);
-        logger.warn('opencode serve exited', { cwd, code });
-      });
-      return { baseUrl, proc, port };
-    }
-
-    logger.warn('opencode serve failed health check, retrying', { cwd, baseUrl, attempt });
-    try {
-      proc.kill();
-    } catch {
-      /* already gone */
-    }
-  }
-
-  throw new Error(`opencode serve failed to start for cwd ${cwd}`);
-}
-
-/** Ensure a healthy `opencode serve` for `cwd`, returning its base URL. Dedupes concurrent starts. */
-export async function ensureServer(cwd: string, home: string): Promise<{ baseUrl: string }> {
-  const existing = servers.get(cwd);
-  if (existing && (await isHealthy(existing.baseUrl))) {
-    return { baseUrl: existing.baseUrl };
-  }
-  if (existing) {
-    try {
-      existing.proc.kill();
-    } catch {
-      /* already gone */
-    }
-    servers.delete(cwd);
-  }
-
-  const inflight = starting.get(cwd);
-  if (inflight) {
-    const s = await inflight;
-    return { baseUrl: s.baseUrl };
-  }
-
-  const promise = startServer(cwd, home);
-  starting.set(cwd, promise);
-  try {
-    const server = await promise;
-    servers.set(cwd, server);
-    return { baseUrl: server.baseUrl };
-  } finally {
-    starting.delete(cwd);
-  }
+/** The base URL of the fixed OpenCode server. */
+export async function ensureServer(): Promise<{ baseUrl: string }> {
+  return { baseUrl: OPENCODE_SERVER_URL };
 }

src/servers/channels/send-opencode.ts

@@ -4,7 +4,6 @@ import { ensureServer } from '@@/api/chat/opencode/server-manager';
 import { getConnection } from '@@/api/chat/opencode/client';
 import { createEventMapper } from '@@/api/chat/opencode/event-mapper';
 import { getOpenCodeSession, setOpenCodeSession } from '@@/api/chat/opencode/state';
-import { getHomeDirForRole } from '../data-path';
 
 // The OpenCode analog of send-claude-code.ts's streaming path. Drives a turn against a warm
 // `opencode serve` over HTTP + SSE, mapping events to the shared ChatEvent contract.
@@ -34,22 +33,19 @@ function splitModel(model: string): { providerID: string; modelID: string } {
 }
 
 export async function sendOpenCodeStreaming(params: OpenCodeStreamingParams): Promise<OpenCodeStreamingHandle> {
-  const home = getHomeDirForRole(params.email, params.role ?? '');
-  const cwd = params.cwd || home;
-
   logger.info('OpenCode streaming exec', { sessionKey: params.sessionKey, model: params.model });
 
-  const { baseUrl } = await ensureServer(cwd, home);
+  const { baseUrl } = await ensureServer();
   const conn = getConnection(baseUrl);
 
   // Resolve the OpenCode session: a known mapping, or — when resuming from history — the sessionKey is
-  // itself the OpenCode session id (`ses_…`); otherwise create one bound to the cwd.
+  // itself the OpenCode session id (`ses_…`); otherwise create a new one.
   let opencodeSessionId =
     getOpenCodeSession(params.sessionKey) ??
     (params.sessionKey.startsWith('ses_') ? params.sessionKey : undefined) ??
     params.resumeSessionId;
   if (!opencodeSessionId) {
-    opencodeSessionId = await conn.createSession(cwd);
+    opencodeSessionId = await conn.createSession();
   }
   setOpenCodeSession(params.sessionKey, opencodeSessionId);
   const sessionId = opencodeSessionId;