diff --git a/packages/ui/src/components/permission-approval-modal.tsx b/packages/ui/src/components/permission-approval-modal.tsx
index 4e2aff614..33b6d2d32 100644
--- a/packages/ui/src/components/permission-approval-modal.tsx
+++ b/packages/ui/src/components/permission-approval-modal.tsx
@@ -12,6 +12,7 @@ import {
 } from "../stores/instances"
 import { ensureSessionParentExpanded, loadMessages, sessions as sessionStateSessions, setActiveSessionFromList } from "../stores/sessions"
 import { messageStoreBus } from "../stores/message-v2/bus"
+import { PERMISSION_REJECT_REASON_MAX_LENGTH } from "./tool-call/permission-constants"
 
 const LazyToolCall = lazy(() => import("./tool-call"))
 
@@ -136,6 +137,8 @@ const PermissionApprovalModal: Component<PermissionApprovalModalProps> = (props)
   const [loadingSession, setLoadingSession] = createSignal<string | null>(null)
   const [permissionSubmitting, setPermissionSubmitting] = createSignal<Set<string>>(new Set())
   const [permissionError, setPermissionError] = createSignal<Map<string, string>>(new Map())
+  const [rejectingPermissionId, setRejectingPermissionId] = createSignal<string | null>(null)
+  const [rejectReason, setRejectReason] = createSignal("")
 
   const setPermissionBusy = (permissionId: string, busy: boolean) => {
     setPermissionSubmitting((prev) => {
@@ -155,7 +158,7 @@ const PermissionApprovalModal: Component<PermissionApprovalModalProps> = (props)
     })
   }
 
-  async function handlePermissionDecision(permission: PermissionRequestLike, response: "once" | "always" | "reject") {
+  async function handlePermissionDecision(permission: PermissionRequestLike, response: "once" | "always" | "reject", message?: string) {
     const permissionId = permission?.id
     if (!permissionId) return
 
@@ -166,7 +169,11 @@ const PermissionApprovalModal: Component<PermissionApprovalModalProps> = (props)
 
     try {
       const sessionId = getPermissionSessionId(permission) || ""
-      await sendPermissionResponse(props.instanceId, sessionId, permissionId, response)
+      await sendPermissionResponse(props.instanceId, sessionId, permissionId, response, message)
+      if (rejectingPermissionId() === permissionId) {
+        setRejectingPermissionId(null)
+        setRejectReason("")
+      }
     } catch (error) {
       setPermissionItemError(
         permissionId,
@@ -370,34 +377,86 @@ const PermissionApprovalModal: Component<PermissionApprovalModalProps> = (props)
                                   <code>{primaryTitle()}</code>
                                 </div>
                                 <Show when={item.kind === "permission"}>
-                                  <div class="tool-call-permission-actions">
-                                    <div class="tool-call-permission-buttons">
-                                      <button
-                                        type="button"
-                                        class="tool-call-permission-button"
-                                        disabled={permissionSubmitting().has(item.id)}
-                                        onClick={() => void handlePermissionDecision(item.payload as PermissionRequestLike, "once")}
-                                      >
-                                        {t("permissionApproval.actions.allowOnce")}
-                                      </button>
-                                      <button
-                                        type="button"
-                                        class="tool-call-permission-button"
+                                  <Show
+                                    when={rejectingPermissionId() === item.id}
+                                    fallback={
+                                      <div class="tool-call-permission-actions">
+                                        <div class="tool-call-permission-buttons">
+                                          <button
+                                            type="button"
+                                            class="tool-call-permission-button"
+                                            disabled={permissionSubmitting().has(item.id)}
+                                            onClick={() => void handlePermissionDecision(item.payload as PermissionRequestLike, "once")}
+                                          >
+                                            {t("permissionApproval.actions.allowOnce")}
+                                          </button>
+                                          <button
+                                            type="button"
+                                            class="tool-call-permission-button"
+                                            disabled={permissionSubmitting().has(item.id)}
+                                            onClick={() => void handlePermissionDecision(item.payload as PermissionRequestLike, "always")}
+                                          >
+                                            {t("permissionApproval.actions.alwaysAllow")}
+                                          </button>
+                                          <button
+                                            type="button"
+                                            class="tool-call-permission-button"
+                                            disabled={permissionSubmitting().has(item.id)}
+                                            onClick={() => {
+                                              setRejectingPermissionId(item.id)
+                                              setRejectReason("")
+                                            }}
+                                          >
+                                            {t("permissionApproval.actions.deny")}
+                                          </button>
+                                        </div>
+                                      </div>
+                                    }
+                                  >
+                                    <div class="tool-call-permission-reject-reason">
+                                      <label class="tool-call-permission-reject-label" for={`permission-center-reject-reason-${item.id}`}>
+                                        {t("permissionApproval.rejectReason.label")}
+                                      </label>
+                                      <textarea
+                                        id={`permission-center-reject-reason-${item.id}`}
+                                        class="tool-call-permission-reject-textarea"
+                                        value={rejectReason()}
+                                        rows={3}
+                                        maxLength={PERMISSION_REJECT_REASON_MAX_LENGTH}
+                                        placeholder={t("permissionApproval.rejectReason.placeholder")}
                                         disabled={permissionSubmitting().has(item.id)}
-                                        onClick={() => void handlePermissionDecision(item.payload as PermissionRequestLike, "always")}
-                                      >
-                                        {t("permissionApproval.actions.alwaysAllow")}
-                                      </button>
-                                      <button
-                                        type="button"
-                                        class="tool-call-permission-button"
-                                        disabled={permissionSubmitting().has(item.id)}
-                                        onClick={() => void handlePermissionDecision(item.payload as PermissionRequestLike, "reject")}
-                                      >
-                                        {t("permissionApproval.actions.deny")}
-                                      </button>
+                                        onInput={(event) => setRejectReason(event.currentTarget.value)}
+                                      />
+                                      <p class="tool-call-permission-reject-hint">{t("permissionApproval.rejectReason.hint")}</p>
+                                      <div class="tool-call-permission-buttons">
+                                        <button
+                                          type="button"
+                                          class="tool-call-permission-button"
+                                          disabled={permissionSubmitting().has(item.id)}
+                                          onClick={() =>
+                                            void handlePermissionDecision(
+                                              item.payload as PermissionRequestLike,
+                                              "reject",
+                                              rejectReason().trim() || undefined,
+                                            )
+                                          }
+                                        >
+                                          {t("permissionApproval.actions.confirmDeny")}
+                                        </button>
+                                        <button
+                                          type="button"
+                                          class="tool-call-permission-button"
+                                          disabled={permissionSubmitting().has(item.id)}
+                                          onClick={() => {
+                                            setRejectingPermissionId(null)
+                                            setRejectReason("")
+                                          }}
+                                        >
+                                          {t("permissionApproval.actions.cancel")}
+                                        </button>
+                                      </div>
                                     </div>
-                                  </div>
+                                  </Show>
                                   <Show when={permissionError().get(item.id)}>
                                     {(err) => <div class="tool-call-permission-error">{err()}</div>}
                                   </Show>
diff --git a/packages/ui/src/components/tool-call.tsx b/packages/ui/src/components/tool-call.tsx
index af9be1ebd..cc10fceea 100644
--- a/packages/ui/src/components/tool-call.tsx
+++ b/packages/ui/src/components/tool-call.tsx
@@ -186,6 +186,7 @@ function ToolCallDetails(props: {
 
   const [permissionSubmitting, setPermissionSubmitting] = createSignal(false)
   const [permissionError, setPermissionError] = createSignal<string | null>(null)
+  const [permissionRejectReasonOpen, setPermissionRejectReasonOpen] = createSignal(false)
 
   const followScroll = createFollowScroll({
     getScrollTopSnapshot: props.scrollTopSnapshot,
@@ -225,13 +226,13 @@ function ToolCallDetails(props: {
     })
   })
 
-  async function handlePermissionResponse(permission: PermissionRequestLike, response: "once" | "always" | "reject") {
+  async function handlePermissionResponse(permission: PermissionRequestLike, response: "once" | "always" | "reject", message?: string) {
     if (!permission) return
     setPermissionSubmitting(true)
     setPermissionError(null)
     try {
       const sessionId = getPermissionSessionId(permission) || props.sessionId
-      await sendPermissionResponse(props.instanceId, sessionId, permission.id, response)
+      await sendPermissionResponse(props.instanceId, sessionId, permission.id, response, message)
     } catch (error) {
       log.error("Failed to send permission response", error)
       setPermissionError(error instanceof Error ? error.message : props.t("toolCall.permission.errors.unableToUpdate"))
@@ -244,6 +245,8 @@ function ToolCallDetails(props: {
     const activeKey = activePermissionKey()
     if (!activeKey) return
     const handler = (event: KeyboardEvent) => {
+      if (isTextInputFocused()) return
+      if (permissionRejectReasonOpen()) return
       const permission = permissionDetails()
       if (!permission || !props.isPermissionActive()) return
       if (event.key === "Enter") {
@@ -252,9 +255,6 @@ function ToolCallDetails(props: {
       } else if (event.key === "a" || event.key === "A") {
         event.preventDefault()
         void handlePermissionResponse(permission, "always")
-      } else if (event.key === "d" || event.key === "D") {
-        event.preventDefault()
-        void handlePermissionResponse(permission, "reject")
       }
     }
     document.addEventListener("keydown", handler)
@@ -483,7 +483,8 @@ function ToolCallDetails(props: {
       error={permissionError}
       renderDiff={renderDiffContent}
       fallbackSessionId={() => props.sessionId}
-      onRespond={(permission, sessionId, response) => void handlePermissionResponse(permission, response)}
+      onRejectReasonOpenChange={setPermissionRejectReasonOpen}
+      onRespond={(permission, sessionId, response, message) => void handlePermissionResponse(permission, response, message)}
     />
   )
 
diff --git a/packages/ui/src/components/tool-call/permission-block.tsx b/packages/ui/src/components/tool-call/permission-block.tsx
index a8493f7ab..100b8bf43 100644
--- a/packages/ui/src/components/tool-call/permission-block.tsx
+++ b/packages/ui/src/components/tool-call/permission-block.tsx
@@ -1,8 +1,9 @@
-import { Show, type Accessor, type JSXElement } from "solid-js"
+import { Show, createEffect, createSignal, type Accessor, type JSXElement } from "solid-js"
 import type { PermissionRequestLike } from "../../types/permission"
 import { getPermissionDisplayTitle, getPermissionKind } from "../../types/permission"
 import { getPermissionSessionId } from "../../types/permission"
 import { useI18n } from "../../lib/i18n"
+import { PERMISSION_REJECT_REASON_MAX_LENGTH } from "./permission-constants"
 import type { DiffPayload, DiffRenderOptions } from "./types"
 import { getRelativePath } from "./utils"
 
@@ -13,13 +14,27 @@ export type PermissionToolBlockProps = {
   active: Accessor<boolean>
   submitting: Accessor<boolean>
   error: Accessor<string | null>
-  onRespond: (permission: PermissionRequestLike, sessionId: string, response: PermissionResponse) => void | Promise<void>
+  onRespond: (permission: PermissionRequestLike, sessionId: string, response: PermissionResponse, message?: string) => void | Promise<void>
+  onRejectReasonOpenChange?: (open: boolean) => void
   renderDiff: (payload: DiffPayload, options?: DiffRenderOptions) => JSXElement | null
   fallbackSessionId: Accessor<string>
 }
 
 export function PermissionToolBlock(props: PermissionToolBlockProps) {
   const { t } = useI18n()
+  const [showRejectReason, setShowRejectReason] = createSignal(false)
+  const [rejectReason, setRejectReason] = createSignal("")
+
+  const setRejectReasonOpen = (open: boolean) => {
+    setShowRejectReason(open)
+    props.onRejectReasonOpenChange?.(open)
+  }
+
+  createEffect(() => {
+    props.permission()?.id
+    setRejectReasonOpen(false)
+    setRejectReason("")
+  })
 
   const diffPayload = () => {
     const permission = props.permission()
@@ -39,11 +54,15 @@ export function PermissionToolBlock(props: PermissionToolBlockProps) {
     return { diffText: diffValue, filePath: diffPathRaw } satisfies DiffPayload
   }
 
-  const respond = (response: PermissionResponse) => {
+  const respond = (response: PermissionResponse, message?: string) => {
     const permission = props.permission()
     if (!permission) return
     const sessionId = getPermissionSessionId(permission) || props.fallbackSessionId()
-    props.onRespond(permission, sessionId, response)
+    props.onRespond(permission, sessionId, response, message)
+  }
+
+  const confirmReject = () => {
+    respond("reject", rejectReason().trim() || undefined)
   }
 
   return (
@@ -76,44 +95,80 @@ export function PermissionToolBlock(props: PermissionToolBlockProps) {
             <Show when={!props.active()}>
               <p class="tool-call-permission-queued-text">{t("toolCall.permission.queuedText")}</p>
             </Show>
-            <div class="tool-call-permission-actions">
-              <div class="tool-call-permission-buttons">
-                <button
-                  type="button"
-                  class="tool-call-permission-button"
-                  disabled={props.submitting()}
-                  onClick={() => respond("once")}
-                >
-                  {t("toolCall.permission.actions.allowOnce")}
-                </button>
-                <button
-                  type="button"
-                  class="tool-call-permission-button"
-                  disabled={props.submitting()}
-                  onClick={() => respond("always")}
-                >
-                  {t("toolCall.permission.actions.alwaysAllow")}
-                </button>
-                <button
-                  type="button"
-                  class="tool-call-permission-button"
+            <Show
+              when={showRejectReason()}
+              fallback={
+                <div class="tool-call-permission-actions">
+                  <div class="tool-call-permission-buttons">
+                    <button
+                      type="button"
+                      class="tool-call-permission-button"
+                      disabled={props.submitting()}
+                      onClick={() => respond("once")}
+                    >
+                      {t("toolCall.permission.actions.allowOnce")}
+                    </button>
+                    <button
+                      type="button"
+                      class="tool-call-permission-button"
+                      disabled={props.submitting()}
+                      onClick={() => respond("always")}
+                    >
+                      {t("toolCall.permission.actions.alwaysAllow")}
+                    </button>
+                    <button
+                      type="button"
+                      class="tool-call-permission-button"
+                      disabled={props.submitting()}
+                      onClick={() => setRejectReasonOpen(true)}
+                    >
+                      {t("toolCall.permission.actions.deny")}
+                    </button>
+                  </div>
+                  <Show when={props.active()}>
+                    <div class="tool-call-permission-shortcuts">
+                      <kbd class="kbd">Enter</kbd>
+                      <span>{t("toolCall.permission.shortcuts.allowOnce")}</span>
+                      <kbd class="kbd">A</kbd>
+                      <span>{t("toolCall.permission.shortcuts.alwaysAllow")}</span>
+                    </div>
+                  </Show>
+                </div>
+              }
+            >
+              <div class="tool-call-permission-reject-reason">
+                <label class="tool-call-permission-reject-label" for={`permission-reject-reason-${permission().id}`}>
+                  {t("toolCall.permission.rejectReason.label")}
+                </label>
+                <textarea
+                  id={`permission-reject-reason-${permission().id}`}
+                  class="tool-call-permission-reject-textarea"
+                  value={rejectReason()}
+                  rows={3}
+                  maxLength={PERMISSION_REJECT_REASON_MAX_LENGTH}
+                  placeholder={t("toolCall.permission.rejectReason.placeholder")}
                   disabled={props.submitting()}
-                  onClick={() => respond("reject")}
-                >
-                  {t("toolCall.permission.actions.deny")}
-                </button>
-              </div>
-              <Show when={props.active()}>
-                <div class="tool-call-permission-shortcuts">
-                  <kbd class="kbd">Enter</kbd>
-                  <span>{t("toolCall.permission.shortcuts.allowOnce")}</span>
-                  <kbd class="kbd">A</kbd>
-                  <span>{t("toolCall.permission.shortcuts.alwaysAllow")}</span>
-                  <kbd class="kbd">D</kbd>
-                  <span>{t("toolCall.permission.shortcuts.deny")}</span>
+                  onInput={(event) => setRejectReason(event.currentTarget.value)}
+                />
+                <p class="tool-call-permission-reject-hint">{t("toolCall.permission.rejectReason.hint")}</p>
+                <div class="tool-call-permission-buttons">
+                  <button type="button" class="tool-call-permission-button" disabled={props.submitting()} onClick={confirmReject}>
+                    {t("toolCall.permission.actions.confirmDeny")}
+                  </button>
+                  <button
+                    type="button"
+                    class="tool-call-permission-button"
+                    disabled={props.submitting()}
+                    onClick={() => {
+                      setRejectReasonOpen(false)
+                      setRejectReason("")
+                    }}
+                  >
+                    {t("toolCall.permission.actions.cancel")}
+                  </button>
                 </div>
-              </Show>
-            </div>
+              </div>
+            </Show>
             <Show when={props.error()}>
               <div class="tool-call-permission-error">{props.error()}</div>
             </Show>
diff --git a/packages/ui/src/components/tool-call/permission-constants.ts b/packages/ui/src/components/tool-call/permission-constants.ts
new file mode 100644
index 000000000..0e31a4288
--- /dev/null
+++ b/packages/ui/src/components/tool-call/permission-constants.ts
@@ -0,0 +1 @@
+export const PERMISSION_REJECT_REASON_MAX_LENGTH = 2000
diff --git a/packages/ui/src/lib/i18n/messages/en/toolCall.ts b/packages/ui/src/lib/i18n/messages/en/toolCall.ts
index 6d1736f5c..cc52103d6 100644
--- a/packages/ui/src/lib/i18n/messages/en/toolCall.ts
+++ b/packages/ui/src/lib/i18n/messages/en/toolCall.ts
@@ -71,9 +71,13 @@ export const toolCallMessages = {
   "toolCall.permission.actions.allowOnce": "Allow Once",
   "toolCall.permission.actions.alwaysAllow": "Always Allow",
   "toolCall.permission.actions.deny": "Deny",
+  "toolCall.permission.actions.confirmDeny": "Confirm Deny",
+  "toolCall.permission.actions.cancel": "Cancel",
   "toolCall.permission.shortcuts.allowOnce": "Allow once",
   "toolCall.permission.shortcuts.alwaysAllow": "Always allow",
-  "toolCall.permission.shortcuts.deny": "Deny",
+  "toolCall.permission.rejectReason.label": "Why deny this permission?",
+  "toolCall.permission.rejectReason.placeholder": "Tell CodeNomad what to do differently...",
+  "toolCall.permission.rejectReason.hint": "The agent will see this feedback and can adjust its next action.",
   "toolCall.permission.errors.unableToUpdate": "Unable to update permission",
 
   "permissionApproval.title": "Requests",
@@ -90,6 +94,11 @@ export const toolCallMessages = {
   "permissionApproval.actions.allowOnce": "Allow Once",
   "permissionApproval.actions.alwaysAllow": "Always Allow",
   "permissionApproval.actions.deny": "Deny",
+  "permissionApproval.actions.confirmDeny": "Confirm Deny",
+  "permissionApproval.actions.cancel": "Cancel",
+  "permissionApproval.rejectReason.label": "Why deny this permission?",
+  "permissionApproval.rejectReason.placeholder": "Tell CodeNomad what to do differently...",
+  "permissionApproval.rejectReason.hint": "The agent will see this feedback and can adjust its next action.",
   "permissionApproval.fallbackHint": "Load session for more information.",
   "permissionApproval.errors.unableToUpdatePermission": "Unable to update permission",
 
diff --git a/packages/ui/src/lib/i18n/messages/es/toolCall.ts b/packages/ui/src/lib/i18n/messages/es/toolCall.ts
index 52422359d..ca9b4f809 100644
--- a/packages/ui/src/lib/i18n/messages/es/toolCall.ts
+++ b/packages/ui/src/lib/i18n/messages/es/toolCall.ts
@@ -71,9 +71,13 @@ export const toolCallMessages = {
   "toolCall.permission.actions.allowOnce": "Permitir una vez",
   "toolCall.permission.actions.alwaysAllow": "Permitir siempre",
   "toolCall.permission.actions.deny": "Denegar",
+  "toolCall.permission.actions.confirmDeny": "Confirmar denegación",
+  "toolCall.permission.actions.cancel": "Cancelar",
   "toolCall.permission.shortcuts.allowOnce": "Permitir una vez",
   "toolCall.permission.shortcuts.alwaysAllow": "Permitir siempre",
-  "toolCall.permission.shortcuts.deny": "Denegar",
+  "toolCall.permission.rejectReason.label": "¿Por qué denegar este permiso?",
+  "toolCall.permission.rejectReason.placeholder": "Indica a CodeNomad qué debe hacer de otra forma...",
+  "toolCall.permission.rejectReason.hint": "El agente verá estos comentarios y podrá ajustar su siguiente acción.",
   "toolCall.permission.errors.unableToUpdate": "No se pudo actualizar el permiso",
 
   "permissionApproval.title": "Solicitudes",
@@ -90,6 +94,11 @@ export const toolCallMessages = {
   "permissionApproval.actions.allowOnce": "Permitir una vez",
   "permissionApproval.actions.alwaysAllow": "Permitir siempre",
   "permissionApproval.actions.deny": "Denegar",
+  "permissionApproval.actions.confirmDeny": "Confirmar denegación",
+  "permissionApproval.actions.cancel": "Cancelar",
+  "permissionApproval.rejectReason.label": "¿Por qué denegar este permiso?",
+  "permissionApproval.rejectReason.placeholder": "Indica a CodeNomad qué debe hacer de otra forma...",
+  "permissionApproval.rejectReason.hint": "El agente verá estos comentarios y podrá ajustar su siguiente acción.",
   "permissionApproval.fallbackHint": "Carga la sesión para más información.",
   "permissionApproval.errors.unableToUpdatePermission": "No se pudo actualizar el permiso",
 
diff --git a/packages/ui/src/lib/i18n/messages/fr/toolCall.ts b/packages/ui/src/lib/i18n/messages/fr/toolCall.ts
index 6cab1b0a1..3827a1fd9 100644
--- a/packages/ui/src/lib/i18n/messages/fr/toolCall.ts
+++ b/packages/ui/src/lib/i18n/messages/fr/toolCall.ts
@@ -71,9 +71,13 @@ export const toolCallMessages = {
   "toolCall.permission.actions.allowOnce": "Autoriser une fois",
   "toolCall.permission.actions.alwaysAllow": "Toujours autoriser",
   "toolCall.permission.actions.deny": "Refuser",
+  "toolCall.permission.actions.confirmDeny": "Confirmer le refus",
+  "toolCall.permission.actions.cancel": "Annuler",
   "toolCall.permission.shortcuts.allowOnce": "Autoriser une fois",
   "toolCall.permission.shortcuts.alwaysAllow": "Toujours autoriser",
-  "toolCall.permission.shortcuts.deny": "Refuser",
+  "toolCall.permission.rejectReason.label": "Pourquoi refuser cette autorisation ?",
+  "toolCall.permission.rejectReason.placeholder": "Indiquez à CodeNomad quoi faire différemment...",
+  "toolCall.permission.rejectReason.hint": "L'agent verra ce retour et pourra ajuster sa prochaine action.",
   "toolCall.permission.errors.unableToUpdate": "Impossible de mettre à jour l'autorisation",
 
   "permissionApproval.title": "Demandes",
@@ -90,6 +94,11 @@ export const toolCallMessages = {
   "permissionApproval.actions.allowOnce": "Autoriser une fois",
   "permissionApproval.actions.alwaysAllow": "Toujours autoriser",
   "permissionApproval.actions.deny": "Refuser",
+  "permissionApproval.actions.confirmDeny": "Confirmer le refus",
+  "permissionApproval.actions.cancel": "Annuler",
+  "permissionApproval.rejectReason.label": "Pourquoi refuser cette autorisation ?",
+  "permissionApproval.rejectReason.placeholder": "Indiquez à CodeNomad quoi faire différemment...",
+  "permissionApproval.rejectReason.hint": "L'agent verra ce retour et pourra ajuster sa prochaine action.",
   "permissionApproval.fallbackHint": "Chargez la session pour plus d'informations.",
   "permissionApproval.errors.unableToUpdatePermission": "Impossible de mettre à jour l'autorisation",
 
diff --git a/packages/ui/src/lib/i18n/messages/he/toolCall.ts b/packages/ui/src/lib/i18n/messages/he/toolCall.ts
index 578dd2446..7aebdb263 100644
--- a/packages/ui/src/lib/i18n/messages/he/toolCall.ts
+++ b/packages/ui/src/lib/i18n/messages/he/toolCall.ts
@@ -71,9 +71,13 @@ export const toolCallMessages = {
   "toolCall.permission.actions.allowOnce": "אפשר פעם אחת",
   "toolCall.permission.actions.alwaysAllow": "אפשר תמיד",
   "toolCall.permission.actions.deny": "דחה",
+  "toolCall.permission.actions.confirmDeny": "אשר דחייה",
+  "toolCall.permission.actions.cancel": "בטל",
   "toolCall.permission.shortcuts.allowOnce": "אפשר פעם אחת",
   "toolCall.permission.shortcuts.alwaysAllow": "אפשר תמיד",
-  "toolCall.permission.shortcuts.deny": "דחה",
+  "toolCall.permission.rejectReason.label": "למה לדחות את האישור הזה?",
+  "toolCall.permission.rejectReason.placeholder": "ספר ל-CodeNomad מה לעשות אחרת...",
+  "toolCall.permission.rejectReason.hint": "הסוכן יראה את המשוב הזה ויוכל להתאים את הפעולה הבאה שלו.",
   "toolCall.permission.errors.unableToUpdate": "לא ניתן לעדכן אישור",
 
   "permissionApproval.title": "בקשות",
@@ -90,6 +94,11 @@ export const toolCallMessages = {
   "permissionApproval.actions.allowOnce": "אפשר פעם אחת",
   "permissionApproval.actions.alwaysAllow": "אפשר תמיד",
   "permissionApproval.actions.deny": "דחה",
+  "permissionApproval.actions.confirmDeny": "אשר דחייה",
+  "permissionApproval.actions.cancel": "בטל",
+  "permissionApproval.rejectReason.label": "למה לדחות את האישור הזה?",
+  "permissionApproval.rejectReason.placeholder": "ספר ל-CodeNomad מה לעשות אחרת...",
+  "permissionApproval.rejectReason.hint": "הסוכן יראה את המשוב הזה ויוכל להתאים את הפעולה הבאה שלו.",
   "permissionApproval.fallbackHint": "טען סשן לקבלת מידע נוסף.",
   "permissionApproval.errors.unableToUpdatePermission": "לא ניתן לעדכן אישור",
 
diff --git a/packages/ui/src/lib/i18n/messages/ja/toolCall.ts b/packages/ui/src/lib/i18n/messages/ja/toolCall.ts
index 58e6ad1f0..1dc0e0127 100644
--- a/packages/ui/src/lib/i18n/messages/ja/toolCall.ts
+++ b/packages/ui/src/lib/i18n/messages/ja/toolCall.ts
@@ -71,9 +71,13 @@ export const toolCallMessages = {
   "toolCall.permission.actions.allowOnce": "一度だけ許可",
   "toolCall.permission.actions.alwaysAllow": "常に許可",
   "toolCall.permission.actions.deny": "拒否",
+  "toolCall.permission.actions.confirmDeny": "拒否を確定",
+  "toolCall.permission.actions.cancel": "キャンセル",
   "toolCall.permission.shortcuts.allowOnce": "一度だけ許可",
   "toolCall.permission.shortcuts.alwaysAllow": "常に許可",
-  "toolCall.permission.shortcuts.deny": "拒否",
+  "toolCall.permission.rejectReason.label": "この許可を拒否する理由は？",
+  "toolCall.permission.rejectReason.placeholder": "CodeNomad に別の対応を伝えてください...",
+  "toolCall.permission.rejectReason.hint": "エージェントはこのフィードバックを見て、次の操作を調整できます。",
   "toolCall.permission.errors.unableToUpdate": "許可を更新できません",
 
   "permissionApproval.title": "リクエスト",
@@ -90,6 +94,11 @@ export const toolCallMessages = {
   "permissionApproval.actions.allowOnce": "一度だけ許可",
   "permissionApproval.actions.alwaysAllow": "常に許可",
   "permissionApproval.actions.deny": "拒否",
+  "permissionApproval.actions.confirmDeny": "拒否を確定",
+  "permissionApproval.actions.cancel": "キャンセル",
+  "permissionApproval.rejectReason.label": "この許可を拒否する理由は？",
+  "permissionApproval.rejectReason.placeholder": "CodeNomad に別の対応を伝えてください...",
+  "permissionApproval.rejectReason.hint": "エージェントはこのフィードバックを見て、次の操作を調整できます。",
   "permissionApproval.fallbackHint": "詳しい情報を見るにはセッションを読み込んでください。",
   "permissionApproval.errors.unableToUpdatePermission": "許可を更新できません",
 
diff --git a/packages/ui/src/lib/i18n/messages/ru/toolCall.ts b/packages/ui/src/lib/i18n/messages/ru/toolCall.ts
index 54f24020b..9548ead7a 100644
--- a/packages/ui/src/lib/i18n/messages/ru/toolCall.ts
+++ b/packages/ui/src/lib/i18n/messages/ru/toolCall.ts
@@ -71,9 +71,13 @@ export const toolCallMessages = {
   "toolCall.permission.actions.allowOnce": "Разрешить один раз",
   "toolCall.permission.actions.alwaysAllow": "Всегда разрешать",
   "toolCall.permission.actions.deny": "Запретить",
+  "toolCall.permission.actions.confirmDeny": "Подтвердить отказ",
+  "toolCall.permission.actions.cancel": "Отмена",
   "toolCall.permission.shortcuts.allowOnce": "Разрешить один раз",
   "toolCall.permission.shortcuts.alwaysAllow": "Всегда разрешать",
-  "toolCall.permission.shortcuts.deny": "Запретить",
+  "toolCall.permission.rejectReason.label": "Почему отказать в этом разрешении?",
+  "toolCall.permission.rejectReason.placeholder": "Подскажите CodeNomad, что сделать иначе...",
+  "toolCall.permission.rejectReason.hint": "Агент увидит этот отзыв и сможет скорректировать следующее действие.",
   "toolCall.permission.errors.unableToUpdate": "Не удалось обновить разрешение",
 
   "permissionApproval.title": "Запросы",
@@ -90,6 +94,11 @@ export const toolCallMessages = {
   "permissionApproval.actions.allowOnce": "Разрешить один раз",
   "permissionApproval.actions.alwaysAllow": "Всегда разрешать",
   "permissionApproval.actions.deny": "Запретить",
+  "permissionApproval.actions.confirmDeny": "Подтвердить отказ",
+  "permissionApproval.actions.cancel": "Отмена",
+  "permissionApproval.rejectReason.label": "Почему отказать в этом разрешении?",
+  "permissionApproval.rejectReason.placeholder": "Подскажите CodeNomad, что сделать иначе...",
+  "permissionApproval.rejectReason.hint": "Агент увидит этот отзыв и сможет скорректировать следующее действие.",
   "permissionApproval.fallbackHint": "Загрузите сессию для получения подробностей.",
   "permissionApproval.errors.unableToUpdatePermission": "Не удалось обновить разрешение",
 
diff --git a/packages/ui/src/lib/i18n/messages/zh-Hans/toolCall.ts b/packages/ui/src/lib/i18n/messages/zh-Hans/toolCall.ts
index eae5a29bc..c378470fb 100644
--- a/packages/ui/src/lib/i18n/messages/zh-Hans/toolCall.ts
+++ b/packages/ui/src/lib/i18n/messages/zh-Hans/toolCall.ts
@@ -71,9 +71,13 @@ export const toolCallMessages = {
   "toolCall.permission.actions.allowOnce": "仅允许一次",
   "toolCall.permission.actions.alwaysAllow": "始终允许",
   "toolCall.permission.actions.deny": "拒绝",
+  "toolCall.permission.actions.confirmDeny": "确认拒绝",
+  "toolCall.permission.actions.cancel": "取消",
   "toolCall.permission.shortcuts.allowOnce": "仅允许一次",
   "toolCall.permission.shortcuts.alwaysAllow": "始终允许",
-  "toolCall.permission.shortcuts.deny": "拒绝",
+  "toolCall.permission.rejectReason.label": "为什么拒绝此权限？",
+  "toolCall.permission.rejectReason.placeholder": "告诉 CodeNomad 应该如何调整...",
+  "toolCall.permission.rejectReason.hint": "代理会看到这条反馈，并可调整下一步操作。",
   "toolCall.permission.errors.unableToUpdate": "无法更新权限",
 
   "permissionApproval.title": "请求",
@@ -90,6 +94,11 @@ export const toolCallMessages = {
   "permissionApproval.actions.allowOnce": "仅允许一次",
   "permissionApproval.actions.alwaysAllow": "始终允许",
   "permissionApproval.actions.deny": "拒绝",
+  "permissionApproval.actions.confirmDeny": "确认拒绝",
+  "permissionApproval.actions.cancel": "取消",
+  "permissionApproval.rejectReason.label": "为什么拒绝此权限？",
+  "permissionApproval.rejectReason.placeholder": "告诉 CodeNomad 应该如何调整...",
+  "permissionApproval.rejectReason.hint": "代理会看到这条反馈，并可调整下一步操作。",
   "permissionApproval.fallbackHint": "加载会话以查看更多信息。",
   "permissionApproval.errors.unableToUpdatePermission": "无法更新权限",
 
diff --git a/packages/ui/src/stores/instances.ts b/packages/ui/src/stores/instances.ts
index ccf14f160..d087d3c27 100644
--- a/packages/ui/src/stores/instances.ts
+++ b/packages/ui/src/stores/instances.ts
@@ -1088,7 +1088,8 @@ async function sendPermissionResponse(
   instanceId: string,
   sessionId: string,
   requestId: string,
-  reply: PermissionReply
+  reply: PermissionReply,
+  message?: string,
 ): Promise<void> {
   const instance = instances().get(instanceId)
   if (!instance?.client) {
@@ -1105,6 +1106,7 @@ async function sendPermissionResponse(
       client.permission.reply({
         requestID: requestId,
         reply,
+        ...(message ? { message } : {}),
       }),
       "permission.reply",
     )
diff --git a/packages/ui/src/styles/messaging/tool-call.css b/packages/ui/src/styles/messaging/tool-call.css
index 3758cd521..014e1454c 100644
--- a/packages/ui/src/styles/messaging/tool-call.css
+++ b/packages/ui/src/styles/messaging/tool-call.css
@@ -515,6 +515,40 @@
   margin-inline-end: 0.25rem;
 }
 
+.tool-call-permission-reject-reason {
+  @apply flex flex-col gap-2;
+  margin-top: 0.75rem;
+}
+
+.tool-call-permission-reject-label {
+  @apply text-sm;
+  color: var(--text-secondary);
+  font-weight: var(--font-weight-medium);
+}
+
+.tool-call-permission-reject-textarea {
+  width: 100%;
+  min-height: 5rem;
+  resize: vertical;
+  background-color: var(--surface-code);
+  border: 1px solid var(--tool-call-border-color, var(--border-base));
+  border-radius: 0.5rem;
+  color: var(--text-primary);
+  padding: 0.6rem 0.75rem;
+  font-size: 0.85rem;
+  line-height: 1.4;
+}
+
+.tool-call-permission-reject-textarea:focus {
+  outline: none;
+  border-color: var(--status-warning);
+}
+
+.tool-call-permission-reject-hint {
+  @apply text-xs text-muted;
+  margin: 0;
+}
+
 .tool-call-permission-queued-text {
   @apply text-sm text-muted;
 }