diff --git a/.changeset/compact-thinking-level.md b/.changeset/compact-thinking-level.md
new file mode 100644
index 00000000000..a00bd74f635
--- /dev/null
+++ b/.changeset/compact-thinking-level.md
@@ -0,0 +1,6 @@
+---
+"@kilocode/cli": patch
+"kilo-code": patch
+---
+
+Preserve the selected thinking level after compacting a session.
diff --git a/packages/opencode/src/cli/cmd/tui/component/prompt/index.tsx b/packages/opencode/src/cli/cmd/tui/component/prompt/index.tsx
index 8f504683627..c6bb8500f31 100644
--- a/packages/opencode/src/cli/cmd/tui/component/prompt/index.tsx
+++ b/packages/opencode/src/cli/cmd/tui/component/prompt/index.tsx
@@ -43,6 +43,7 @@ import { DialogSkill } from "../dialog-skill"
 import { DialogWorkspaceCreate, restoreWorkspaceSession } from "../dialog-workspace-create"
 import { DialogWorkspaceUnavailable } from "../dialog-workspace-unavailable"
 import { useArgs } from "@tui/context/args"
+import { KiloSessionTuiSync } from "@/kilocode/session/tui-sync" // kilocode_change
 
 export type PromptProps = {
   sessionID?: string
@@ -249,6 +250,11 @@ export function Prompt(props: PromptProps) {
     const sessionID = props.sessionID
     const msg = lastUserMessage()
     if (!sessionID || !msg) return
+    // kilocode_change start - skip compaction messages while syncing local agent/model
+    const parts = sync.data.part[msg.id]
+    if (!parts) return
+    if (!KiloSessionTuiSync.model({ role: msg.role, parts })) return
+    // kilocode_change end
 
     const key = [sessionID, msg.id].join(":")
     if (key === syncedKey) return
diff --git a/packages/opencode/src/kilocode/session/tui-sync.ts b/packages/opencode/src/kilocode/session/tui-sync.ts
new file mode 100644
index 00000000000..26d71f9ba64
--- /dev/null
+++ b/packages/opencode/src/kilocode/session/tui-sync.ts
@@ -0,0 +1,7 @@
+export namespace KiloSessionTuiSync {
+  export function model(input: { role: string; parts?: readonly { type: string }[] }) {
+    if (input.role !== "user") return false
+    if (!input.parts) return false
+    return !input.parts.some((part) => part.type === "compaction")
+  }
+}
diff --git a/packages/opencode/test/kilocode/tui-sync.test.ts b/packages/opencode/test/kilocode/tui-sync.test.ts
new file mode 100644
index 00000000000..e7262ac74e2
--- /dev/null
+++ b/packages/opencode/test/kilocode/tui-sync.test.ts
@@ -0,0 +1,80 @@
+import { describe, expect, test } from "bun:test"
+import { KiloSessionTuiSync } from "../../src/kilocode/session/tui-sync"
+
+type Message = {
+  role: string
+  model?: { providerID: string; modelID: string; variant?: string }
+  parts?: readonly { type: string }[]
+}
+
+function syncVariant(input: { current: string | undefined; message: Message; parts?: readonly { type: string }[] }) {
+  if (!KiloSessionTuiSync.model({ role: input.message.role, parts: input.parts })) return input.current
+  return input.message.model?.variant ?? "default"
+}
+
+describe("KiloSessionTuiSync.model", () => {
+  test("syncs normal user messages", () => {
+    expect(KiloSessionTuiSync.model({ role: "user", parts: [{ type: "text" }] })).toBe(true)
+  })
+
+  test("skips compaction marker user messages", () => {
+    expect(KiloSessionTuiSync.model({ role: "user", parts: [{ type: "compaction" }] })).toBe(false)
+  })
+
+  test("skips messages before parts load", () => {
+    expect(KiloSessionTuiSync.model({ role: "user" })).toBe(false)
+  })
+
+  test("skips messages checked with stored parts", () => {
+    const msg = { role: "user" }
+    const parts = [{ type: "compaction" }]
+
+    expect(KiloSessionTuiSync.model({ role: msg.role, parts })).toBe(false)
+  })
+
+  test("skips non-user messages", () => {
+    expect(KiloSessionTuiSync.model({ role: "assistant", parts: [{ type: "text" }] })).toBe(false)
+  })
+
+  test("preserves thinking level after /compact", () => {
+    const msg = {
+      role: "user",
+      model: { providerID: "anthropic", modelID: "claude-sonnet-4-5" },
+      parts: [{ type: "compaction" }],
+    }
+
+    expect(syncVariant({ current: "high", message: msg, parts: msg.parts })).toBe("high")
+  })
+
+  test("preserves thinking level when compaction parts are stored separately", () => {
+    const msg = {
+      role: "user",
+      model: { providerID: "anthropic", modelID: "claude-sonnet-4-5" },
+    }
+    const parts = [{ type: "compaction" }]
+
+    expect(parts.some((part) => part.type === "compaction")).toBe(true)
+    expect(syncVariant({ current: "high", message: msg, parts })).toBe("high")
+  })
+
+  test("waits for normal user message parts before syncing", () => {
+    const msg = {
+      role: "user",
+      model: { providerID: "anthropic", modelID: "claude-sonnet-4-5", variant: "max" },
+    }
+    const parts = [{ type: "text" }]
+
+    expect(syncVariant({ current: "high", message: msg })).toBe("high")
+    expect(syncVariant({ current: "high", message: msg, parts })).toBe("max")
+  })
+
+  test("still updates thinking level from normal user messages", () => {
+    const msg = {
+      role: "user",
+      model: { providerID: "anthropic", modelID: "claude-sonnet-4-5", variant: "max" },
+      parts: [{ type: "text" }],
+    }
+
+    expect(syncVariant({ current: "high", message: msg, parts: msg.parts })).toBe("max")
+  })
+})