fix: delay codex terminal prompt submission (#226)

* fix: delay codex terminal prompt submission

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix: preserve multiline terminal prompts

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: centdix

backend/src/__tests__/agent-chat-service.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "bun:test";
 import { getAgentDefinition } from "../services/agent-registry";
-import { resolveAgentChatSupport } from "../services/agent-chat-service";
+import { resolveAgentChatSupport, resolveAgentTerminalSubmitDelayMs } from "../services/agent-chat-service";
 import type { ProjectConfig } from "../domain/config";
 
 const TEST_CONFIG: ProjectConfig = {
@@ -99,4 +99,21 @@ describe("resolveAgentChatSupport", () => {
       status: 404,
     });
   });
+
+  it("uses the same terminal submit delay for built-in Codex prompts", () => {
+    expect(resolveAgentTerminalSubmitDelayMs({
+      agentId: "codex",
+      agent: getAgentDefinition(TEST_CONFIG, "codex"),
+    })).toBe(200);
+
+    expect(resolveAgentTerminalSubmitDelayMs({
+      agentId: "claude",
+      agent: getAgentDefinition(TEST_CONFIG, "claude"),
+    })).toBe(0);
+
+    expect(resolveAgentTerminalSubmitDelayMs({
+      agentId: "gemini",
+      agent: getAgentDefinition(TEST_CONFIG, "gemini"),
+    })).toBe(0);
+  });
 });

backend/src/__tests__/terminal-adapter.test.ts

@@ -189,15 +189,16 @@ describe("terminal adapter", () => {
       },
       "reply with EXACTLY OK",
       0,
-      undefined,
+      "Preamble:\n",
       200,
     );
 
     expect(result).toEqual({ ok: true });
     expect(slept).toEqual([200]);
     expect(tmuxCalls).toEqual([
+      ["tmux", "send-keys", "-t", "owner:wm-feature/search.0", "-l", "--", "Preamble:\n"],
       ["tmux", "load-buffer", "-b", expect.stringMatching(/^wm-prompt-/), "-",],
-      ["tmux", "paste-buffer", "-b", expect.stringMatching(/^wm-prompt-/), "-t", "owner:wm-feature/search.0", "-d"],
+      ["tmux", "paste-buffer", "-rp", "-b", expect.stringMatching(/^wm-prompt-/), "-t", "owner:wm-feature/search.0", "-d"],
       ["tmux", "send-keys", "-t", "owner:wm-feature/search.0", "Enter"],
     ]);
   });

backend/src/adapters/terminal.ts

@@ -422,7 +422,7 @@ export async function sendPrompt(
     return { ok: false, error: `load-buffer failed${load.stderr ? `: ${load.stderr}` : ""}` };
   }
 
-  const paste = await tmuxExec(["tmux", "paste-buffer", "-b", bufferName, "-t", paneTarget, "-d"]);
+  const paste = await tmuxExec(["tmux", "paste-buffer", "-rp", "-b", bufferName, "-t", paneTarget, "-d"]);
   if (paste.exitCode !== 0) {
     return { ok: false, error: `paste-buffer failed${paste.stderr ? `: ${paste.stderr}` : ""}` };
   }

backend/src/server.ts

@@ -49,7 +49,7 @@ import { isRecord, isStringArray } from "./lib/type-guards";
 import { parseJsonBody, parseParams, parseQuery } from "./api-validation";
 import { hasRecentDashboardActivity, touchDashboardActivity } from "./services/dashboard-activity";
 import { buildArchivedWorktreePathSet, normalizeArchivePath } from "./services/archive-service";
-import { resolveAgentChatSupport } from "./services/agent-chat-service";
+import { resolveAgentChatSupport, resolveAgentTerminalSubmitDelayMs } from "./services/agent-chat-service";
 import { validateCustomAgentInput } from "./services/agent-validation-service";
 import { getAgentDefinition, isBuiltInAgentId, listAgentDetails, listAgentSummaries, normalizeCustomAgentId } from "./services/agent-registry";
 import {
@@ -319,6 +319,7 @@ async function withRemovingBranch<T>(branch: string, fn: () => Promise<T>): Prom
 async function resolveTerminalWorktree(branch: string): Promise<{
   worktreeId: string;
   attachTarget: TerminalAttachTarget;
+  agentName: WorktreeSnapshot["agentName"];
 }> {
   ensureBranchNotBusy(branch);
   let state = projectRuntime.getWorktreeByBranch(branch);
@@ -339,6 +340,7 @@ async function resolveTerminalWorktree(branch: string): Promise<{
       ownerSessionName: state.session.sessionName,
       windowName: state.session.windowName,
     },
+    agentName: state.agentName,
   };
 }
 
@@ -510,6 +512,13 @@ function resolveWorktreeAgentChatSupport(worktree: WorktreeSnapshot, action: "ch
   });
 }
 
+function resolveWorktreeTerminalSubmitDelayMs(agentName: WorktreeSnapshot["agentName"]): number {
+  return resolveAgentTerminalSubmitDelayMs({
+    agentId: agentName,
+    agent: agentName ? getAgentDefinition(config, agentName) : null,
+  });
+}
+
 async function apiAttachAgentsWorktree(branch: string): Promise<Response> {
   touchDashboardActivity();
   const resolved = await resolveAgentsWorktree(branch);
@@ -929,12 +938,14 @@ async function apiSendPrompt(name: string, req: Request): Promise<Response> {
   const preamble = body.preamble;
   log.info(`[worktree:send] name=${name} text="${text.slice(0, 80)}"`);
   const terminalWorktree = await resolveTerminalWorktree(name);
+  const submitDelayMs = resolveWorktreeTerminalSubmitDelayMs(terminalWorktree.agentName);
   const result = await sendTerminalPrompt(
     terminalWorktree.worktreeId,
     terminalWorktree.attachTarget,
     text,
     0,
     preamble,
+    submitDelayMs,
   );
   if (!result.ok) return errorResponse(result.error, 503);
   return jsonResponse({ ok: true });

backend/src/services/agent-chat-service.ts

@@ -5,6 +5,16 @@ export interface AgentChatSupport {
   submitDelayMs: number;
 }
 
+const CODEX_SUBMIT_DELAY_MS = 200;
+
+export function resolveAgentTerminalSubmitDelayMs(input: {
+  agentId: string | null;
+  agent: AgentDefinition | null;
+}): number {
+  if (!input.agentId || !input.agent || input.agent.kind !== "builtin") return 0;
+  return input.agent.implementation.agent === "codex" ? CODEX_SUBMIT_DELAY_MS : 0;
+}
+
 export function resolveAgentChatSupport(input: {
   agentId: string | null;
   agentLabel: string | null;
@@ -51,7 +61,7 @@ export function resolveAgentChatSupport(input: {
       ok: true,
       data: {
         provider: input.agent.implementation.agent,
-        submitDelayMs: input.agent.implementation.agent === "codex" ? 200 : 0,
+        submitDelayMs: resolveAgentTerminalSubmitDelayMs(input),
       },
     };
   }

frontend/src/App.svelte

@@ -365,15 +365,9 @@
   let terminalRef:
     | {
         sendSelectPane: (pane: number) => void;
-        sendInput: (data: string) => void;
       }
     | undefined = $state();
 
-  // Safety buffer after backend confirms paste-buffer completion.
-  // paste-buffer exits once tmux has queued the data, but the PTY write
-  // may not be fully flushed yet — this small delay lets it settle.
-  const ENTER_DELAY_MS = 200;
-
   let openingBranches = $state<Set<string>>(new Set());
   let archivingBranches = $state<Set<string>>(new Set());
   let trimmedWorktreeSearch = $derived(searchQuery.trim());
@@ -1278,7 +1272,6 @@
     onclose={() => (ciDetailsPr = null)}
     onfixsuccess={() => {
       ciDetailsPr = null;
-      setTimeout(() => terminalRef?.sendInput("\r"), ENTER_DELAY_MS);
     }}
   />
 {/if}
@@ -1290,7 +1283,6 @@
     onclose={() => (commentReviewPr = null)}
     onsendsuccess={() => {
       commentReviewPr = null;
-      setTimeout(() => terminalRef?.sendInput("\r"), ENTER_DELAY_MS);
     }}
   />
 {/if}