diff --git a/packages/opencode/src/mcp/index.ts b/packages/opencode/src/mcp/index.ts
index e48a42a8b..bf5a0d3ce 100644
--- a/packages/opencode/src/mcp/index.ts
+++ b/packages/opencode/src/mcp/index.ts
@@ -11,6 +11,7 @@ import {
 } from "@modelcontextprotocol/sdk/types.js"
 import { Config } from "../config/config"
 import { Log } from "../util/log"
+import { Process } from "../util/process"
 import { NamedError } from "@opencode-ai/util/error"
 import z from "zod/v4"
 import { Instance } from "../project/instance"
@@ -166,14 +167,10 @@ export namespace MCP {
     const queue = [pid]
     while (queue.length > 0) {
       const current = queue.shift()!
-      const proc = Bun.spawn(["pgrep", "-P", String(current)], { stdout: "pipe", stderr: "pipe" })
-      const [code, out] = await Promise.all([proc.exited, new Response(proc.stdout).text()]).catch(
-        () => [-1, ""] as const,
-      )
-      if (code !== 0) continue
-      for (const tok of out.trim().split(/\s+/)) {
+      const lines = await Process.lines(["pgrep", "-P", String(current)], { nothrow: true })
+      for (const tok of lines) {
         const cpid = parseInt(tok, 10)
-        if (!isNaN(cpid) && pids.indexOf(cpid) === -1) {
+        if (!isNaN(cpid) && !pids.includes(cpid)) {
           pids.push(cpid)
           queue.push(cpid)
         }
diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index 36162656a..1cc144c8d 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -32,7 +32,6 @@ import { Flag } from "../flag/flag"
 import { ulid } from "ulid"
 import { spawn } from "child_process"
 import { Command } from "../command"
-import { $ } from "bun"
 import { pathToFileURL, fileURLToPath } from "url"
 import { ConfigMarkdown } from "../config/markdown"
 import { SessionSummary } from "./summary"
@@ -48,6 +47,7 @@ import { iife } from "@/util/iife"
 import { Shell } from "@/shell/shell"
 import { Truncate } from "@/tool/truncate"
 import { decodeDataUrl } from "@/util/data-url"
+import { Process } from "@/util/process"
 
 // @ts-ignore
 globalThis.AI_SDK_LOG_WARNINGS = false
@@ -1812,15 +1812,13 @@ NOTE: At any point in time through this workflow you should feel free to ask the
       template = template + "\n\n" + input.arguments
     }
 
-    const shell = ConfigMarkdown.shell(template)
-    if (shell.length > 0) {
+    const shellMatches = ConfigMarkdown.shell(template)
+    if (shellMatches.length > 0) {
+      const sh = Shell.preferred()
       const results = await Promise.all(
-        shell.map(async ([, cmd]) => {
-          try {
-            return await $`${{ raw: cmd }}`.quiet().nothrow().text()
-          } catch (error) {
-            return `Error executing command: ${error instanceof Error ? error.message : String(error)}`
-          }
+        shellMatches.map(async ([, cmd]) => {
+          const out = await Process.text([cmd], { shell: sh, nothrow: true })
+          return out.text
         }),
       )
       let index = 0