diff --git a/packages/opencode-config/README.md b/packages/opencode-config/README.md
new file mode 100644
index 00000000..28e60bd2
--- /dev/null
+++ b/packages/opencode-config/README.md
@@ -0,0 +1,32 @@
+# opencode-config
+
+## TLDR
+Template config + plugins injected into every OpenCode instance that CodeNomad launches. It provides a CodeNomad bridge plugin for local event exchange between the CLI server and opencode.
+
+## What it is
+A packaged config directory that CodeNomad copies into `~/.config/codenomad/opencode-config` for production builds or uses directly in dev. OpenCode autoloads any `plugin/*.ts` or `plugin/*.js` from this directory.
+
+## How it works
+- CodeNomad sets `OPENCODE_CONFIG_DIR` when spawning each opencode instance (`packages/server/src/workspaces/manager.ts`).
+- This template is synced from `packages/opencode-config` (`packages/server/src/opencode-config.ts`, `packages/server/scripts/copy-opencode-config.mjs`).
+- OpenCode autoloads plugins from `plugin/` (`packages/opencode-config/plugin/codenomad.ts`).
+- The `CodeNomadPlugin` reads `CODENOMAD_INSTANCE_ID` + `CODENOMAD_BASE_URL`, connects to `GET /workspaces/:id/plugin/events`, and posts to `POST /workspaces/:id/plugin/event` (`packages/opencode-config/plugin/lib/client.ts`).
+- The server exposes the plugin routes and maps events into the UI SSE pipeline (`packages/server/src/server/routes/plugin.ts`, `packages/server/src/plugins/handlers.ts`).
+
+## Expectations
+- Local-only bridge (no auth/token yet).
+- Plugin must fail startup if it cannot connect after 3 retries.
+- Keep plugin entrypoints thin; put shared logic under `plugin/lib/` to avoid autoloaded helpers.
+- Keep event shapes small and explicit; use `type` + `properties` only.
+
+## Ideas
+- Add feature modules under `plugin/lib/features/` (tool lifecycle, permission prompts, custom commands).
+- Expand `/workspaces/:id/plugin/*` with dedicated endpoints as needed.
+- Promote stable event shapes and version tags once the protocol settles.
+
+## Pointers
+- Plugin entry: `packages/opencode-config/plugin/codenomad.ts`
+- Plugin client: `packages/opencode-config/plugin/lib/client.ts`
+- Plugin server routes: `packages/server/src/server/routes/plugin.ts`
+- Plugin event handling: `packages/server/src/plugins/handlers.ts`
+- Workspace env injection: `packages/server/src/workspaces/manager.ts`
diff --git a/packages/opencode-config/plugin/codenomad.ts b/packages/opencode-config/plugin/codenomad.ts
new file mode 100644
index 00000000..166cb256
--- /dev/null
+++ b/packages/opencode-config/plugin/codenomad.ts
@@ -0,0 +1,35 @@
+import { createCodeNomadClient, getCodeNomadConfig } from "./lib/client"
+
+export async function CodeNomadPlugin() {
+  const config = getCodeNomadConfig()
+  const client = createCodeNomadClient(config)
+
+  await client.startEvents((event) => {
+    if (event.type === "codenomad.ping") {
+      void client.postEvent({
+        type: "codenomad.pong",
+        properties: {
+          ts: Date.now(),
+          pingTs: (event.properties as any)?.ts,
+        },
+      }).catch(() => {})
+    }
+  })
+
+  return {
+    async event(input: { event: any }) {
+      const opencodeEvent = input?.event
+      if (!opencodeEvent || typeof opencodeEvent !== "object") return
+
+      if (opencodeEvent.type === "session.idle") {
+        const sessionID = (opencodeEvent as any).properties?.sessionID
+        void client.postEvent({
+          type: "opencode.session.idle",
+          properties: {
+            sessionID,
+          },
+        }).catch(() => {})
+      }
+    },
+  }
+}
diff --git a/packages/opencode-config/plugin/lib/client.ts b/packages/opencode-config/plugin/lib/client.ts
new file mode 100644
index 00000000..b6727de4
--- /dev/null
+++ b/packages/opencode-config/plugin/lib/client.ts
@@ -0,0 +1,165 @@
+export type PluginEvent = {
+  type: string
+  properties?: Record<string, unknown>
+}
+
+export type CodeNomadConfig = {
+  instanceId: string
+  baseUrl: string
+}
+
+export function getCodeNomadConfig(): CodeNomadConfig {
+  return {
+    instanceId: requireEnv("CODENOMAD_INSTANCE_ID"),
+    baseUrl: requireEnv("CODENOMAD_BASE_URL"),
+  }
+}
+
+export function createCodeNomadClient(config: CodeNomadConfig) {
+  return {
+    postEvent: (event: PluginEvent) => postPluginEvent(config.baseUrl, config.instanceId, event),
+    startEvents: (onEvent: (event: PluginEvent) => void) => startPluginEvents(config.baseUrl, config.instanceId, onEvent),
+  }
+}
+
+function requireEnv(key: string): string {
+  const value = process.env[key]
+  if (!value || !value.trim()) {
+    throw new Error(`[CodeNomadPlugin] Missing required env var ${key}`)
+  }
+  return value
+}
+
+function delay(ms: number) {
+  return new Promise<void>((resolve) => setTimeout(resolve, ms))
+}
+
+async function postPluginEvent(baseUrl: string, instanceId: string, event: PluginEvent) {
+  const url = `${baseUrl.replace(/\/+$/, "")}/workspaces/${instanceId}/plugin/event`
+  const response = await fetch(url, {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+    },
+    body: JSON.stringify(event),
+  })
+
+  if (!response.ok) {
+    throw new Error(`[CodeNomadPlugin] POST ${url} failed (${response.status})`)
+  }
+}
+
+async function startPluginEvents(baseUrl: string, instanceId: string, onEvent: (event: PluginEvent) => void) {
+  const url = `${baseUrl.replace(/\/+$/, "")}/workspaces/${instanceId}/plugin/events`
+
+  // Fail plugin startup if we cannot establish the initial connection.
+  const initialBody = await connectWithRetries(url, 3)
+
+  // After startup, keep reconnecting; throw after 3 consecutive failures.
+  void consumeWithReconnect(url, onEvent, initialBody)
+}
+
+async function connectWithRetries(url: string, maxAttempts: number) {
+  let lastError: unknown
+
+  for (let attempt = 1; attempt <= maxAttempts; attempt += 1) {
+    try {
+      const response = await fetch(url, { headers: { Accept: "text/event-stream" } })
+      if (!response.ok || !response.body) {
+        throw new Error(`[CodeNomadPlugin] SSE unavailable (${response.status})`)
+      }
+      return response.body
+    } catch (error) {
+      lastError = error
+      await delay(500 * attempt)
+    }
+  }
+
+  const reason = lastError instanceof Error ? lastError.message : String(lastError)
+  throw new Error(`[CodeNomadPlugin] Failed to connect to CodeNomad after ${maxAttempts} retries: ${reason}`)
+}
+
+async function consumeWithReconnect(
+  url: string,
+  onEvent: (event: PluginEvent) => void,
+  initialBody: ReadableStream<Uint8Array>,
+) {
+  let consecutiveFailures = 0
+  let body: ReadableStream<Uint8Array> | null = initialBody
+
+  while (true) {
+    try {
+      if (!body) {
+        body = await connectWithRetries(url, 3)
+      }
+
+      await consumeSseBody(body, onEvent)
+      body = null
+      consecutiveFailures = 0
+    } catch (error) {
+      body = null
+      consecutiveFailures += 1
+      if (consecutiveFailures >= 3) {
+        const reason = error instanceof Error ? error.message : String(error)
+        throw new Error(`[CodeNomadPlugin] Plugin event stream failed after 3 retries: ${reason}`)
+      }
+      await delay(500 * consecutiveFailures)
+    }
+  }
+}
+
+async function consumeSseBody(body: ReadableStream<Uint8Array>, onEvent: (event: PluginEvent) => void) {
+  const reader = body.getReader()
+  const decoder = new TextDecoder()
+  let buffer = ""
+
+  while (true) {
+    const { done, value } = await reader.read()
+    if (done || !value) {
+      break
+    }
+
+    buffer += decoder.decode(value, { stream: true })
+
+    let separatorIndex = buffer.indexOf("\n\n")
+    while (separatorIndex >= 0) {
+      const chunk = buffer.slice(0, separatorIndex)
+      buffer = buffer.slice(separatorIndex + 2)
+      separatorIndex = buffer.indexOf("\n\n")
+
+      const event = parseSseChunk(chunk)
+      if (event) {
+        onEvent(event)
+      }
+    }
+  }
+
+  throw new Error("SSE stream ended")
+}
+
+function parseSseChunk(chunk: string): PluginEvent | null {
+  const lines = chunk.split(/\r?\n/)
+  const dataLines: string[] = []
+
+  for (const line of lines) {
+    if (line.startsWith(":")) continue
+    if (line.startsWith("data:")) {
+      dataLines.push(line.slice(5).trimStart())
+    }
+  }
+
+  if (dataLines.length === 0) return null
+
+  const payload = dataLines.join("\n").trim()
+  if (!payload) return null
+
+  try {
+    const parsed = JSON.parse(payload)
+    if (!parsed || typeof parsed !== "object" || typeof (parsed as any).type !== "string") {
+      return null
+    }
+    return parsed as PluginEvent
+  } catch {
+    return null
+  }
+}
diff --git a/packages/server/src/index.ts b/packages/server/src/index.ts
index 8144faae..6b548402 100644
--- a/packages/server/src/index.ts
+++ b/packages/server/src/index.ts
@@ -122,22 +122,6 @@ async function main() {
   logger.info({ options }, "Starting CodeNomad CLI server")
 
   const eventBus = new EventBus(eventLogger)
-  const configStore = new ConfigStore(options.configPath, eventBus, configLogger)
-  const binaryRegistry = new BinaryRegistry(configStore, eventBus, configLogger)
-  const workspaceManager = new WorkspaceManager({
-    rootDir: options.rootDir,
-    configStore,
-    binaryRegistry,
-    eventBus,
-    logger: workspaceLogger,
-  })
-  const fileSystemBrowser = new FileSystemBrowser({ rootDir: options.rootDir, unrestricted: options.unrestrictedRoot })
-  const instanceStore = new InstanceStore()
-  const instanceEventBridge = new InstanceEventBridge({
-    workspaceManager,
-    eventBus,
-    logger: logger.child({ component: "instance-events" }),
-  })
 
   const serverMeta: ServerMeta = {
     httpBaseUrl: `http://${options.host}:${options.port}`,
@@ -150,6 +134,24 @@ async function main() {
     addresses: [],
   }
 
+  const configStore = new ConfigStore(options.configPath, eventBus, configLogger)
+  const binaryRegistry = new BinaryRegistry(configStore, eventBus, configLogger)
+  const workspaceManager = new WorkspaceManager({
+    rootDir: options.rootDir,
+    configStore,
+    binaryRegistry,
+    eventBus,
+    logger: workspaceLogger,
+    getServerBaseUrl: () => serverMeta.httpBaseUrl,
+  })
+  const fileSystemBrowser = new FileSystemBrowser({ rootDir: options.rootDir, unrestricted: options.unrestrictedRoot })
+  const instanceStore = new InstanceStore()
+  const instanceEventBridge = new InstanceEventBridge({
+    workspaceManager,
+    eventBus,
+    logger: logger.child({ component: "instance-events" }),
+  })
+
   const releaseMonitor = startReleaseMonitor({
     currentVersion: packageJson.version,
     logger: logger.child({ component: "release-monitor" }),
diff --git a/packages/server/src/plugins/channel.ts b/packages/server/src/plugins/channel.ts
new file mode 100644
index 00000000..c4d645ea
--- /dev/null
+++ b/packages/server/src/plugins/channel.ts
@@ -0,0 +1,55 @@
+import type { FastifyReply } from "fastify"
+import type { Logger } from "../logger"
+
+export interface PluginOutboundEvent {
+  type: string
+  properties?: Record<string, unknown>
+}
+
+interface ClientConnection {
+  reply: FastifyReply
+  workspaceId: string
+}
+
+export class PluginChannelManager {
+  private readonly clients = new Set<ClientConnection>()
+
+  constructor(private readonly logger: Logger) {}
+
+  register(workspaceId: string, reply: FastifyReply) {
+    const connection: ClientConnection = { workspaceId, reply }
+    this.clients.add(connection)
+    this.logger.debug({ workspaceId }, "Plugin SSE client connected")
+
+    let closed = false
+    const close = () => {
+      if (closed) return
+      closed = true
+      this.clients.delete(connection)
+      this.logger.debug({ workspaceId }, "Plugin SSE client disconnected")
+    }
+
+    return { close }
+  }
+
+  send(workspaceId: string, event: PluginOutboundEvent) {
+    for (const client of this.clients) {
+      if (client.workspaceId !== workspaceId) continue
+      this.write(client.reply, event)
+    }
+  }
+
+  broadcast(event: PluginOutboundEvent) {
+    for (const client of this.clients) {
+      this.write(client.reply, event)
+    }
+  }
+
+  private write(reply: FastifyReply, event: PluginOutboundEvent) {
+    try {
+      reply.raw.write(`data: ${JSON.stringify(event)}\n\n`)
+    } catch (error) {
+      this.logger.warn({ err: error }, "Failed to write plugin SSE event")
+    }
+  }
+}
diff --git a/packages/server/src/plugins/handlers.ts b/packages/server/src/plugins/handlers.ts
new file mode 100644
index 00000000..b12432b5
--- /dev/null
+++ b/packages/server/src/plugins/handlers.ts
@@ -0,0 +1,62 @@
+import type { EventBus } from "../events/bus"
+import type { WorkspaceManager } from "../workspaces/manager"
+import type { Logger } from "../logger"
+import type { PluginOutboundEvent } from "./channel"
+
+export interface PluginInboundEvent {
+  type: string
+  properties?: Record<string, unknown>
+}
+
+interface HandlerDeps {
+  workspaceManager: WorkspaceManager
+  eventBus: EventBus
+  logger: Logger
+}
+
+export function handlePluginEvent(workspaceId: string, event: PluginInboundEvent, deps: HandlerDeps) {
+  switch (event.type) {
+    case "codenomad.pong":
+      deps.logger.debug({ workspaceId, properties: event.properties }, "Plugin pong received")
+      return
+
+    case "opencode.session.idle": {
+      const workspace = deps.workspaceManager.get(workspaceId)
+      const title = workspace?.name || workspace?.path?.split(/[\\/]/).filter(Boolean).pop() || "CodeNomad"
+
+      const sessionId = readString(event.properties?.sessionID)
+      const message = sessionId ? `Session ${sessionId} is idle` : "Session is idle"
+
+      deps.eventBus.publish({
+        type: "instance.event",
+        instanceId: workspaceId,
+        event: {
+          type: "tui.toast.show",
+          properties: {
+            title,
+            message,
+            variant: "info",
+            duration: 8000,
+          },
+        },
+      })
+      return
+    }
+
+    default:
+      deps.logger.debug({ workspaceId, eventType: event.type }, "Unhandled plugin event")
+  }
+}
+
+export function buildPingEvent(): PluginOutboundEvent {
+  return {
+    type: "codenomad.ping",
+    properties: {
+      ts: Date.now(),
+    },
+  }
+}
+
+function readString(value: unknown): string | undefined {
+  return typeof value === "string" && value.trim() ? value : undefined
+}
diff --git a/packages/server/src/server/http-server.ts b/packages/server/src/server/http-server.ts
index eb57fb0f..0af7b408 100644
--- a/packages/server/src/server/http-server.ts
+++ b/packages/server/src/server/http-server.ts
@@ -18,6 +18,7 @@ import { registerFilesystemRoutes } from "./routes/filesystem"
 import { registerMetaRoutes } from "./routes/meta"
 import { registerEventRoutes } from "./routes/events"
 import { registerStorageRoutes } from "./routes/storage"
+import { registerPluginRoutes } from "./routes/plugin"
 import { ServerMeta } from "../api-types"
 import { InstanceStore } from "../storage/instance-store"
 
@@ -110,6 +111,7 @@ export function createHttpServer(deps: HttpServerDeps) {
     eventBus: deps.eventBus,
     workspaceManager: deps.workspaceManager,
   })
+  registerPluginRoutes(app, { workspaceManager: deps.workspaceManager, eventBus: deps.eventBus, logger: proxyLogger })
   registerInstanceProxyRoutes(app, { workspaceManager: deps.workspaceManager, logger: proxyLogger })
 
 
diff --git a/packages/server/src/server/routes/plugin.ts b/packages/server/src/server/routes/plugin.ts
new file mode 100644
index 00000000..374ce545
--- /dev/null
+++ b/packages/server/src/server/routes/plugin.ts
@@ -0,0 +1,75 @@
+import { FastifyInstance } from "fastify"
+import { z } from "zod"
+import type { WorkspaceManager } from "../../workspaces/manager"
+import type { EventBus } from "../../events/bus"
+import type { Logger } from "../../logger"
+import { PluginChannelManager } from "../../plugins/channel"
+import { buildPingEvent, handlePluginEvent } from "../../plugins/handlers"
+
+interface RouteDeps {
+  workspaceManager: WorkspaceManager
+  eventBus: EventBus
+  logger: Logger
+}
+
+const PluginEventSchema = z.object({
+  type: z.string().min(1),
+  properties: z.record(z.unknown()).optional(),
+})
+
+export function registerPluginRoutes(app: FastifyInstance, deps: RouteDeps) {
+  const channel = new PluginChannelManager(deps.logger.child({ component: "plugin-channel" }))
+
+  app.get<{ Params: { id: string } }>("/workspaces/:id/plugin/events", (request, reply) => {
+    const workspace = deps.workspaceManager.get(request.params.id)
+    if (!workspace) {
+      reply.code(404).send({ error: "Workspace not found" })
+      return
+    }
+
+    reply.raw.setHeader("Content-Type", "text/event-stream")
+    reply.raw.setHeader("Cache-Control", "no-cache")
+    reply.raw.setHeader("Connection", "keep-alive")
+    reply.raw.flushHeaders?.()
+    reply.hijack()
+
+    const registration = channel.register(request.params.id, reply)
+
+    const heartbeat = setInterval(() => {
+      channel.send(request.params.id, buildPingEvent())
+    }, 15000)
+
+    const close = () => {
+      clearInterval(heartbeat)
+      registration.close()
+      reply.raw.end?.()
+    }
+
+    request.raw.on("close", close)
+    request.raw.on("error", close)
+  })
+
+  const handleWildcard = async (request: any, reply: any) => {
+    const workspaceId = request.params.id as string
+    const workspace = deps.workspaceManager.get(workspaceId)
+    if (!workspace) {
+      reply.code(404).send({ error: "Workspace not found" })
+      return
+    }
+
+    const suffix = (request.params["*"] as string | undefined) ?? ""
+    const normalized = suffix.replace(/^\/+/, "")
+
+    if (normalized === "event" && request.method === "POST") {
+      const parsed = PluginEventSchema.parse(request.body ?? {})
+      handlePluginEvent(workspaceId, parsed, { workspaceManager: deps.workspaceManager, eventBus: deps.eventBus, logger: deps.logger })
+      reply.code(204).send()
+      return
+    }
+
+    reply.code(404).send({ error: "Unknown plugin endpoint" })
+  }
+
+  app.all("/workspaces/:id/plugin/*", handleWildcard)
+  app.all("/workspaces/:id/plugin", handleWildcard)
+}
diff --git a/packages/server/src/workspaces/manager.ts b/packages/server/src/workspaces/manager.ts
index 02af0223..4d93f73a 100644
--- a/packages/server/src/workspaces/manager.ts
+++ b/packages/server/src/workspaces/manager.ts
@@ -20,6 +20,7 @@ interface WorkspaceManagerOptions {
   binaryRegistry: BinaryRegistry
   eventBus: EventBus
   logger: Logger
+  getServerBaseUrl: () => string
 }
 
 interface WorkspaceRecord extends WorkspaceDescriptor {}
@@ -108,6 +109,8 @@ export class WorkspaceManager {
     const environment = {
       ...userEnvironment,
       OPENCODE_CONFIG_DIR: this.opencodeConfigDir,
+      CODENOMAD_INSTANCE_ID: id,
+      CODENOMAD_BASE_URL: this.options.getServerBaseUrl(),
     }
 
     try {