diff --git a/packages/opencode/src/tool/shell.ts b/packages/opencode/src/tool/shell.ts
index 1e4423e01774..c306986dc7ed 100644
--- a/packages/opencode/src/tool/shell.ts
+++ b/packages/opencode/src/tool/shell.ts
@@ -25,6 +25,7 @@ import { BashArity } from "@/permission/arity"
 export { Parameters } from "./shell/prompt"
 
 const MAX_METADATA_LENGTH = 30_000
+const FORCE_KILL_AFTER = "5 seconds"
 const CWD = new Set(["cd", "chdir", "popd", "pushd", "push-location", "set-location"])
 const FILES = new Set([
   ...CWD,
@@ -297,6 +298,7 @@ function cmd(shell: string, command: string, cwd: string, env: NodeJS.ProcessEnv
       env,
       stdin: "ignore",
       detached: false,
+      forceKillAfter: FORCE_KILL_AFTER,
     })
   }
 
@@ -306,6 +308,8 @@ function cmd(shell: string, command: string, cwd: string, env: NodeJS.ProcessEnv
     env,
     stdin: "ignore",
     detached: process.platform !== "win32",
+    // Scope interruption also terminates the process, outside the timeout/abort handlers.
+    forceKillAfter: FORCE_KILL_AFTER,
   })
 }
 const parser = lazy(async () => {
@@ -547,11 +551,11 @@ export const ShellTool = Tool.define(
 
           if (exit.kind === "abort") {
             aborted = true
-            yield* handle.kill({ forceKillAfter: "3 seconds" }).pipe(Effect.orDie)
+            yield* handle.kill({ forceKillAfter: FORCE_KILL_AFTER }).pipe(Effect.orDie)
           }
           if (exit.kind === "timeout") {
             expired = true
-            yield* handle.kill({ forceKillAfter: "3 seconds" }).pipe(Effect.orDie)
+            yield* handle.kill({ forceKillAfter: FORCE_KILL_AFTER }).pipe(Effect.orDie)
           }
 
           return exit.kind === "exit" ? exit.code : null
diff --git a/packages/opencode/test/tool/shell.test.ts b/packages/opencode/test/tool/shell.test.ts
index a970f85d468f..c3c05ae6292a 100644
--- a/packages/opencode/test/tool/shell.test.ts
+++ b/packages/opencode/test/tool/shell.test.ts
@@ -1,7 +1,7 @@
 import { PermissionV1 } from "@opencode-ai/core/v1/permission"
 import { describe, expect } from "bun:test"
 import { LayerNode } from "@opencode-ai/core/effect/layer-node"
-import { Cause, Effect, Exit, Layer } from "effect"
+import { Cause, Deferred, Effect, Exit, Fiber, Layer } from "effect"
 import type * as Scope from "effect/Scope"
 import os from "os"
 import path from "path"
@@ -1007,6 +1007,35 @@ describe("tool.shell permissions", () => {
 })
 
 describe("tool.shell abort", () => {
+  it.live(
+    "bounds cleanup when an interrupted command ignores SIGTERM",
+    () =>
+      runIn(
+        projectRoot,
+        Effect.gen(function* () {
+          if (process.platform === "win32") return
+          const ready = yield* Deferred.make<void>()
+          const fiber = yield* run(
+            {
+              command: `${bin} -e 'process.on("SIGTERM", () => {}); console.log("ready"); setTimeout(() => {}, 20000)'`,
+            },
+            {
+              ...ctx,
+              metadata: (input) =>
+                String(input.metadata?.output).includes("ready")
+                  ? Deferred.succeed(ready, undefined).pipe(Effect.asVoid)
+                  : Effect.void,
+            },
+          ).pipe(Effect.forkScoped)
+          yield* Deferred.await(ready)
+          yield* Fiber.interrupt(fiber)
+          const exit = yield* Fiber.await(fiber)
+          expect(Exit.isFailure(exit)).toBe(true)
+        }),
+      ),
+    15_000,
+  )
+
   it.live(
     "preserves output when aborted",
     () =>