feat(plugin): add session title rename tool

packages/opencode-config/plugin/codenomad.ts

@@ -1,13 +1,15 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { createCodeNomadClient, getCodeNomadConfig } from "./lib/client"
 import { createBackgroundProcessTools } from "./lib/background-process"
+import { createSessionTools } from "./lib/session"
 
 let voiceModeEnabled = false
 
 export async function CodeNomadPlugin(input: PluginInput) {
   const config = getCodeNomadConfig()
   const client = createCodeNomadClient(config)
   const backgroundProcessTools = createBackgroundProcessTools(config, { baseDir: input.directory })
+  const sessionTools = createSessionTools(config)
 
   await client.startEvents((event) => {
     if (event.type === "codenomad.ping") {
@@ -29,6 +31,7 @@ export async function CodeNomadPlugin(input: PluginInput) {
   return {
     tool: {
       ...backgroundProcessTools,
+      ...sessionTools,
     },
     async "chat.message"(_input: { sessionID: string }, output: { message: { system?: string } }) {
       if (!voiceModeEnabled) {

packages/opencode-config/plugin/lib/session.ts

@@ -0,0 +1,49 @@
+import { tool } from "@opencode-ai/plugin/tool"
+import { createCodeNomadRequester, type CodeNomadConfig } from "./request"
+
+type SessionRenameResponse = {
+  sessionID: string
+  title: string
+}
+
+export function createSessionTools(config: CodeNomadConfig) {
+  const requester = createCodeNomadRequester(config)
+
+  const request = async <T>(path: string, init?: RequestInit): Promise<T> => {
+    return requester.requestJson<T>(path, init)
+  }
+
+  return {
+    rename_session: tool({
+      description:
+        "Rename the current session when the user asks to change the chat title. Use a short descriptive title that reflects the current task.",
+      args: {
+        title: tool.schema
+          .string()
+          .describe("New session title, kept short and descriptive, for example 'Fix login bug' or 'Add session rename tool'"),
+      },
+      async execute(args, context) {
+        const sessionID = context.sessionID
+        if (!sessionID) {
+          return "Error: No active session is available for renaming."
+        }
+
+        const trimmedTitle = args.title.trim()
+        if (!trimmedTitle) {
+          return "Error: Session title cannot be empty."
+        }
+
+        const result = await request<SessionRenameResponse>("/session/title", {
+          method: "POST",
+          body: JSON.stringify({
+            sessionID,
+            directory: context.directory,
+            title: trimmedTitle,
+          }),
+        })
+
+        return `Renamed session ${result.sessionID} to \"${result.title}\".`
+      },
+    }),
+  }
+}

packages/server/src/server/routes/plugin.ts

@@ -27,6 +27,12 @@ const VoiceModeStateSchema = z.object({
   connectionId: z.string().trim().min(1),
 })
 
+const SessionTitleUpdateSchema = z.object({
+  sessionID: z.string().trim().min(1),
+  directory: z.string().trim().min(1).optional(),
+  title: z.string().trim().min(1),
+})
+
 export function registerPluginRoutes(app: FastifyInstance, deps: RouteDeps) {
   app.get<{ Params: { id: string } }>("/workspaces/:id/plugin/events", (request, reply) => {
     const workspace = deps.workspaceManager.get(request.params.id)
@@ -92,6 +98,49 @@ export function registerPluginRoutes(app: FastifyInstance, deps: RouteDeps) {
       return
     }
 
+    if (normalized === "session/title" && request.method === "POST") {
+      const parsed = SessionTitleUpdateSchema.parse(request.body ?? {})
+      const port = deps.workspaceManager.getInstancePort(workspaceId)
+      if (!port) {
+        reply.code(502).send({ error: "Workspace instance is not ready" })
+        return
+      }
+
+      const params = new URLSearchParams()
+      if (parsed.directory) {
+        params.set("directory", parsed.directory)
+      }
+
+      const targetUrl = `http://127.0.0.1:${port}/session/${encodeURIComponent(parsed.sessionID)}${params.size > 0 ? `?${params.toString()}` : ""}`
+      const headers: Record<string, string> = {
+        "content-type": "application/json",
+      }
+
+      const authorization = deps.workspaceManager.getInstanceAuthorizationHeader(workspaceId)
+      if (authorization) {
+        headers.authorization = authorization
+      }
+
+      const response = await fetch(targetUrl, {
+        method: "PATCH",
+        headers,
+        body: JSON.stringify({ title: parsed.title }),
+      })
+
+      if (!response.ok) {
+        const message = await response.text().catch(() => "")
+        reply.code(response.status).send({ error: message || `Session update failed with ${response.status}` })
+        return
+      }
+
+      const payload = (await response.json().catch(() => null)) as { id?: string; title?: string } | null
+      reply.send({
+        sessionID: payload?.id ?? parsed.sessionID,
+        title: payload?.title ?? parsed.title,
+      })
+      return
+    }
+
     reply.code(404).send({ error: "Unknown plugin endpoint" })
   }