diff --git a/src-tauri/src/types.rs b/src-tauri/src/types.rs
index f0d0092bc..a9f63daab 100644
--- a/src-tauri/src/types.rs
+++ b/src-tauri/src/types.rs
@@ -591,6 +591,11 @@ pub(crate) struct AppSettings {
         rename = "gitDiffIgnoreWhitespaceChanges"
     )]
     pub(crate) git_diff_ignore_whitespace_changes: bool,
+    #[serde(
+        default = "default_git_pull_request_prompt",
+        rename = "gitPullRequestPrompt"
+    )]
+    pub(crate) git_pull_request_prompt: String,
     #[serde(
         default = "default_system_notifications_enabled",
         rename = "systemNotificationsEnabled"
@@ -924,6 +929,20 @@ fn default_git_diff_ignore_whitespace_changes() -> bool {
     false
 }
 
+fn default_git_pull_request_prompt() -> String {
+    [
+        "You are reviewing a GitHub pull request.",
+        "PR: #{{number}} {{title}}",
+        "URL: {{url}}",
+        "Author: @{{author}}",
+        "Branches: {{baseRef}} <- {{headRef}}",
+        "Updated: {{updatedAt}}{{draftState}}{{descriptionSection}}",
+        "",
+        "Diff: {{diffSummary}}{{questionSection}}",
+    ]
+    .join("\n")
+}
+
 fn default_experimental_collab_enabled() -> bool {
     false
 }
@@ -1169,6 +1188,7 @@ impl Default for AppSettings {
             system_notifications_enabled: true,
             preload_git_diffs: default_preload_git_diffs(),
             git_diff_ignore_whitespace_changes: default_git_diff_ignore_whitespace_changes(),
+            git_pull_request_prompt: default_git_pull_request_prompt(),
             experimental_collab_enabled: false,
             collaboration_modes_enabled: true,
             steer_enabled: true,
@@ -1329,6 +1349,10 @@ mod tests {
         assert!(settings.system_notifications_enabled);
         assert!(settings.preload_git_diffs);
         assert!(!settings.git_diff_ignore_whitespace_changes);
+        assert_eq!(
+            settings.git_pull_request_prompt,
+            default_git_pull_request_prompt()
+        );
         assert!(settings.collaboration_modes_enabled);
         assert!(settings.steer_enabled);
         assert!(settings.unified_exec_enabled);
diff --git a/src/App.tsx b/src/App.tsx
index 98eaf16d5..5156d6b93 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1543,6 +1543,7 @@ function MainApp() {
     activeWorkspace,
     selectedPullRequest,
     gitPullRequestDiffs,
+    gitPullRequestPromptTemplate: appSettings.gitPullRequestPrompt,
     filePanelMode,
     gitPanelMode,
     centerMode,
diff --git a/src/features/git/hooks/usePullRequestComposer.test.tsx b/src/features/git/hooks/usePullRequestComposer.test.tsx
index 210c07189..33ea9b724 100644
--- a/src/features/git/hooks/usePullRequestComposer.test.tsx
+++ b/src/features/git/hooks/usePullRequestComposer.test.tsx
@@ -54,6 +54,7 @@ const makeOptions = (overrides: Partial<Parameters<typeof usePullRequestComposer
   activeWorkspace: connectedWorkspace,
   selectedPullRequest: null,
   gitPullRequestDiffs: diffs,
+  gitPullRequestPromptTemplate: "Default template",
   filePanelMode: "git" as const,
   gitPanelMode: "prs" as const,
   centerMode: "diff" as const,
@@ -141,6 +142,7 @@ describe("usePullRequestComposer", () => {
       pullRequest,
       diffs,
       "Question?",
+      "Default template",
     );
     expect(options.startThreadForWorkspace).toHaveBeenCalledWith(
       disconnectedWorkspace.id,
@@ -193,6 +195,7 @@ describe("usePullRequestComposer", () => {
       pullRequest,
       diffs,
       "/src-tauri/something",
+      "Default template",
     );
     expect(options.startThreadForWorkspace).toHaveBeenCalledWith(
       connectedWorkspace.id,
diff --git a/src/features/git/hooks/usePullRequestComposer.ts b/src/features/git/hooks/usePullRequestComposer.ts
index 08a050b86..342754495 100644
--- a/src/features/git/hooks/usePullRequestComposer.ts
+++ b/src/features/git/hooks/usePullRequestComposer.ts
@@ -11,6 +11,7 @@ type UsePullRequestComposerOptions = {
   activeWorkspace: WorkspaceInfo | null;
   selectedPullRequest: GitHubPullRequest | null;
   gitPullRequestDiffs: GitHubPullRequestDiff[];
+  gitPullRequestPromptTemplate: string;
   filePanelMode: "git" | "files" | "prompts";
   gitPanelMode: "diff" | "log" | "issues" | "prs";
   centerMode: "chat" | "diff";
@@ -40,6 +41,7 @@ export function usePullRequestComposer({
   activeWorkspace,
   selectedPullRequest,
   gitPullRequestDiffs,
+  gitPullRequestPromptTemplate,
   filePanelMode,
   gitPanelMode,
   centerMode,
@@ -120,6 +122,7 @@ export function usePullRequestComposer({
         selectedPullRequest,
         gitPullRequestDiffs,
         trimmed,
+        gitPullRequestPromptTemplate,
       );
       const threadId = await startThreadForWorkspace(activeWorkspace.id, {
         activate: false,
@@ -135,6 +138,7 @@ export function usePullRequestComposer({
       clearActiveImages,
       connectWorkspace,
       gitPullRequestDiffs,
+      gitPullRequestPromptTemplate,
       handleSend,
       selectedPullRequest,
       sendUserMessageToThread,
diff --git a/src/features/settings/components/SettingsView.test.tsx b/src/features/settings/components/SettingsView.test.tsx
index e8ee54ac6..09862590e 100644
--- a/src/features/settings/components/SettingsView.test.tsx
+++ b/src/features/settings/components/SettingsView.test.tsx
@@ -11,6 +11,7 @@ import {
 import type { ComponentProps } from "react";
 import { describe, expect, it, vi } from "vitest";
 import type { AppSettings, WorkspaceInfo } from "../../../types";
+import { DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE } from "../../../utils/pullRequestPrompt";
 import { SettingsView } from "./SettingsView";
 
 vi.mock("@tauri-apps/plugin-dialog", () => ({
@@ -68,6 +69,7 @@ const baseSettings: AppSettings = {
   systemNotificationsEnabled: true,
   preloadGitDiffs: true,
   gitDiffIgnoreWhitespaceChanges: false,
+  gitPullRequestPrompt: DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE,
   experimentalCollabEnabled: false,
   collaborationModesEnabled: true,
   steerEnabled: true,
diff --git a/src/features/settings/components/SettingsView.tsx b/src/features/settings/components/SettingsView.tsx
index c808e62e5..c0777d8ec 100644
--- a/src/features/settings/components/SettingsView.tsx
+++ b/src/features/settings/components/SettingsView.tsx
@@ -36,6 +36,7 @@ import {
   clampCodeFontSize,
   normalizeFontFamily,
 } from "../../../utils/fonts";
+import { DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE } from "../../../utils/pullRequestPrompt";
 import { useGlobalAgentsMd } from "../hooks/useGlobalAgentsMd";
 import { useGlobalCodexConfigToml } from "../hooks/useGlobalCodexConfigToml";
 import { useSettingsOpenAppDrafts } from "../hooks/useSettingsOpenAppDrafts";
@@ -208,6 +209,10 @@ export function SettingsView({
   );
   const [orbitAccessClientSecretRefDraft, setOrbitAccessClientSecretRefDraft] =
     useState(appSettings.orbitAccessClientSecretRef ?? "");
+  const [gitPullRequestPromptDraft, setGitPullRequestPromptDraft] = useState(
+    appSettings.gitPullRequestPrompt,
+  );
+  const [gitPullRequestPromptSaving, setGitPullRequestPromptSaving] = useState(false);
   const [orbitStatusText, setOrbitStatusText] = useState<string | null>(null);
   const [orbitAuthCode, setOrbitAuthCode] = useState<string | null>(null);
   const [orbitVerificationUrl, setOrbitVerificationUrl] = useState<string | null>(
@@ -419,6 +424,10 @@ export function SettingsView({
     setOrbitAccessClientSecretRefDraft(appSettings.orbitAccessClientSecretRef ?? "");
   }, [appSettings.orbitAccessClientSecretRef]);
 
+  useEffect(() => {
+    setGitPullRequestPromptDraft(appSettings.gitPullRequestPrompt);
+  }, [appSettings.gitPullRequestPrompt]);
+
   useEffect(() => {
     setScaleDraft(`${Math.round(clampUiScale(appSettings.uiScale) * 100)}%`);
   }, [appSettings.uiScale]);
@@ -528,6 +537,8 @@ export function SettingsView({
   const codexDirty =
     nextCodexBin !== (appSettings.codexBin ?? null) ||
     nextCodexArgs !== (appSettings.codexArgs ?? null);
+  const gitPullRequestPromptDirty =
+    gitPullRequestPromptDraft !== appSettings.gitPullRequestPrompt;
 
   const trimmedScale = scaleDraft.trim();
   const parsedPercent = trimmedScale
@@ -548,6 +559,43 @@ export function SettingsView({
     }
   };
 
+  const handleSaveGitPullRequestPrompt = useCallback(async () => {
+    if (!gitPullRequestPromptDirty) {
+      return;
+    }
+    const nextValue = gitPullRequestPromptDraft.trim()
+      ? gitPullRequestPromptDraft
+      : DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE;
+    setGitPullRequestPromptSaving(true);
+    setGitPullRequestPromptDraft(nextValue);
+    try {
+      await onUpdateAppSettings({
+        ...appSettings,
+        gitPullRequestPrompt: nextValue,
+      });
+    } finally {
+      setGitPullRequestPromptSaving(false);
+    }
+  }, [
+    appSettings,
+    gitPullRequestPromptDirty,
+    gitPullRequestPromptDraft,
+    onUpdateAppSettings,
+  ]);
+
+  const handleResetGitPullRequestPrompt = useCallback(async () => {
+    setGitPullRequestPromptSaving(true);
+    setGitPullRequestPromptDraft(DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE);
+    try {
+      await onUpdateAppSettings({
+        ...appSettings,
+        gitPullRequestPrompt: DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE,
+      });
+    } finally {
+      setGitPullRequestPromptSaving(false);
+    }
+  }, [appSettings, onUpdateAppSettings]);
+
   const updateRemoteBackendSettings = useCallback(
     async ({
       host,
@@ -1431,6 +1479,12 @@ export function SettingsView({
             <SettingsGitSection
               appSettings={appSettings}
               onUpdateAppSettings={onUpdateAppSettings}
+              gitPullRequestPromptDraft={gitPullRequestPromptDraft}
+              gitPullRequestPromptDirty={gitPullRequestPromptDirty}
+              gitPullRequestPromptSaving={gitPullRequestPromptSaving}
+              onSetGitPullRequestPromptDraft={setGitPullRequestPromptDraft}
+              onSaveGitPullRequestPrompt={handleSaveGitPullRequestPrompt}
+              onResetGitPullRequestPrompt={handleResetGitPullRequestPrompt}
             />
           )}
           {activeSection === "server" && (
diff --git a/src/features/settings/components/sections/SettingsGitSection.tsx b/src/features/settings/components/sections/SettingsGitSection.tsx
index 4f054bcb0..da9b4dfde 100644
--- a/src/features/settings/components/sections/SettingsGitSection.tsx
+++ b/src/features/settings/components/sections/SettingsGitSection.tsx
@@ -3,17 +3,29 @@ import type { AppSettings } from "../../../../types";
 type SettingsGitSectionProps = {
   appSettings: AppSettings;
   onUpdateAppSettings: (next: AppSettings) => Promise<void>;
+  gitPullRequestPromptDraft: string;
+  gitPullRequestPromptDirty: boolean;
+  gitPullRequestPromptSaving: boolean;
+  onSetGitPullRequestPromptDraft: (next: string) => void;
+  onSaveGitPullRequestPrompt: () => Promise<void>;
+  onResetGitPullRequestPrompt: () => Promise<void>;
 };
 
 export function SettingsGitSection({
   appSettings,
   onUpdateAppSettings,
+  gitPullRequestPromptDraft,
+  gitPullRequestPromptDirty,
+  gitPullRequestPromptSaving,
+  onSetGitPullRequestPromptDraft,
+  onSaveGitPullRequestPrompt,
+  onResetGitPullRequestPrompt,
 }: SettingsGitSectionProps) {
   return (
     <section className="settings-section">
       <div className="settings-section-title">Git</div>
       <div className="settings-section-subtitle">
-        Manage how diffs are loaded in the Git sidebar.
+        Manage how diffs are loaded and pull request prompts are composed.
       </div>
       <div className="settings-toggle-row">
         <div>
@@ -55,6 +67,47 @@ export function SettingsGitSection({
           <span className="settings-toggle-knob" />
         </button>
       </div>
+      <div className="settings-field">
+        <label className="settings-field-label" htmlFor="git-pr-prompt">
+          Pull request prompt
+        </label>
+        <div className="settings-help">
+          Template used when asking questions about GitHub pull requests. Available tokens:{" "}
+          <code>{"{{number}}"}</code>, <code>{"{{title}}"}</code>,{" "}
+          <code>{"{{url}}"}</code>, <code>{"{{author}}"}</code>,{" "}
+          <code>{"{{baseRef}}"}</code>, <code>{"{{headRef}}"}</code>,{" "}
+          <code>{"{{updatedAt}}"}</code>, <code>{"{{draftState}}"}</code>,{" "}
+          <code>{"{{descriptionSection}}"}</code>, <code>{"{{diffSummary}}"}</code>,{" "}
+          <code>{"{{questionSection}}"}</code>.
+        </div>
+        <textarea
+          id="git-pr-prompt"
+          className="settings-agents-textarea"
+          value={gitPullRequestPromptDraft}
+          onChange={(event) => onSetGitPullRequestPromptDraft(event.target.value)}
+          placeholder="Describe the pull request context for Codex…"
+          spellCheck={false}
+          disabled={gitPullRequestPromptSaving}
+        />
+        <div className="settings-field-actions">
+          <button
+            type="button"
+            className="ghost settings-button-compact"
+            onClick={() => void onResetGitPullRequestPrompt()}
+            disabled={gitPullRequestPromptSaving}
+          >
+            Reset
+          </button>
+          <button
+            type="button"
+            className="primary settings-button-compact"
+            onClick={() => void onSaveGitPullRequestPrompt()}
+            disabled={gitPullRequestPromptSaving || !gitPullRequestPromptDirty}
+          >
+            {gitPullRequestPromptSaving ? "Saving..." : "Save"}
+          </button>
+        </div>
+      </div>
     </section>
   );
 }
diff --git a/src/features/settings/hooks/useAppSettings.ts b/src/features/settings/hooks/useAppSettings.ts
index d82f37d10..48365003f 100644
--- a/src/features/settings/hooks/useAppSettings.ts
+++ b/src/features/settings/hooks/useAppSettings.ts
@@ -17,6 +17,7 @@ import {
 import { normalizeOpenAppTargets } from "../../app/utils/openApp";
 import { getDefaultInterruptShortcut, isMacPlatform } from "../../../utils/shortcuts";
 import { isMobilePlatform } from "../../../utils/platformPaths";
+import { DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE } from "../../../utils/pullRequestPrompt";
 
 const allowedThemes = new Set(["system", "light", "dark", "dim"]);
 const allowedPersonality = new Set(["friendly", "pragmatic"]);
@@ -72,6 +73,7 @@ function buildDefaultSettings(): AppSettings {
     systemNotificationsEnabled: true,
     preloadGitDiffs: true,
     gitDiffIgnoreWhitespaceChanges: false,
+    gitPullRequestPrompt: DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE,
     experimentalCollabEnabled: false,
     collaborationModesEnabled: true,
     steerEnabled: true,
@@ -133,6 +135,9 @@ function normalizeAppSettings(settings: AppSettings): AppSettings {
       DEFAULT_CODE_FONT_FAMILY,
     ),
     codeFontSize: clampCodeFontSize(settings.codeFontSize),
+    gitPullRequestPrompt: settings.gitPullRequestPrompt?.trim()
+      ? settings.gitPullRequestPrompt
+      : DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE,
     personality: allowedPersonality.has(settings.personality)
       ? settings.personality
       : "friendly",
diff --git a/src/types.ts b/src/types.ts
index ca6f7a405..6e3f0f220 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -190,6 +190,7 @@ export type AppSettings = {
   systemNotificationsEnabled: boolean;
   preloadGitDiffs: boolean;
   gitDiffIgnoreWhitespaceChanges: boolean;
+  gitPullRequestPrompt: string;
   experimentalCollabEnabled: boolean;
   collaborationModesEnabled: boolean;
   steerEnabled: boolean;
diff --git a/src/utils/pullRequestPrompt.ts b/src/utils/pullRequestPrompt.ts
index 064def75a..8cf68ec9a 100644
--- a/src/utils/pullRequestPrompt.ts
+++ b/src/utils/pullRequestPrompt.ts
@@ -1,5 +1,16 @@
 import type { GitHubPullRequest, GitHubPullRequestDiff } from "../types";
 
+export const DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE = `You are reviewing a GitHub pull request.
+PR: #{{number}} {{title}}
+URL: {{url}}
+Author: @{{author}}
+Branches: {{baseRef}} <- {{headRef}}
+Updated: {{updatedAt}}{{draftState}}{{descriptionSection}}
+
+Diff: {{diffSummary}}{{questionSection}}`;
+
+const TEMPLATE_TOKEN_REGEX = /{{\s*([a-zA-Z0-9_]+)\s*}}/g;
+
 export function buildPullRequestDraft(pullRequest: GitHubPullRequest) {
   return `Question about PR #${pullRequest.number} (${pullRequest.title}):\n`;
 }
@@ -8,36 +19,40 @@ export function buildPullRequestPrompt(
   pullRequest: GitHubPullRequest,
   diffs: GitHubPullRequestDiff[],
   question: string,
+  template: string = DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE,
 ) {
   const author = pullRequest.author?.login ?? "unknown";
-  const lines: string[] = [
-    "You are reviewing a GitHub pull request.",
-    `PR: #${pullRequest.number} ${pullRequest.title}`,
-    `URL: ${pullRequest.url}`,
-    `Author: @${author}`,
-    `Branches: ${pullRequest.baseRefName} <- ${pullRequest.headRefName}`,
-    `Updated: ${pullRequest.updatedAt}`,
-  ];
-
-  if (pullRequest.isDraft) {
-    lines.push("State: draft");
-  }
-
-  const body = pullRequest.body?.trim();
-  if (body) {
-    lines.push("", "Description:", body);
-  }
-
-  const diffNote =
+  const diffSummary =
     diffs.length === 0
-      ? "Diff: unavailable in this message."
-      : `Diff: ${diffs.length} file${diffs.length === 1 ? "" : "s"} changed (not included).`;
-  lines.push("", diffNote);
-
+      ? "unavailable in this message."
+      : `${diffs.length} file${diffs.length === 1 ? "" : "s"} changed (not included).`;
+  const draftState = pullRequest.isDraft ? "\nState: draft" : "";
+  const body = pullRequest.body?.trim();
+  const descriptionSection = body ? `\n\nDescription:\n${body}` : "";
   const trimmedQuestion = question.trim();
-  if (trimmedQuestion) {
-    lines.push("", "Question:", trimmedQuestion);
-  }
+  const questionSection = trimmedQuestion
+    ? `\n\nQuestion:\n${trimmedQuestion}`
+    : "";
+  const resolvedTemplate = template.trim()
+    ? template
+    : DEFAULT_PULL_REQUEST_PROMPT_TEMPLATE;
+  const valueMap: Record<string, string> = {
+    number: pullRequest.number.toString(),
+    title: pullRequest.title,
+    url: pullRequest.url,
+    author,
+    baseRef: pullRequest.baseRefName,
+    headRef: pullRequest.headRefName,
+    updatedAt: pullRequest.updatedAt,
+    draftState,
+    descriptionSection,
+    diffSummary,
+    questionSection,
+  };
+  const filled = resolvedTemplate.replace(
+    TEMPLATE_TOKEN_REGEX,
+    (_, key) => valueMap[key] ?? "",
+  );
 
-  return lines.join("\n");
+  return filled.replace(/\n{3,}/g, "\n\n").trim();
 }