harivansh-afk/clanker-agent
1
1
Fork 0
mirror of https://github.com/harivansh-afk/clanker-agent.git synced 2026-04-15 07:04:45 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

fix: add default timeout and no-output timeout to bash tool

Browse source 
Bash tool had no default timeout, so commands like `npx serve` would
block the agent loop forever. This caused the randomtrends sandbox
thread to die - the LLM started a dev server, the shell never exited,
and the entire session hung with no way to recover.

Two safeguards:
- Default 120s timeout when LLM does not specify one
- 30s no-output timeout that kills processes that go silent

Both are configurable via BashToolOptions and can be disabled by
setting to 0. The LLM can still pass explicit higher timeouts for
long builds.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This commit is contained in:
Harivansh Rathi 2026-03-07 19:28:50 -08:00
parent 19f11932e4
commit 479124d945
1 changed files with 75 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

80
packages/coding-agent/src/core/tools/bash.ts
View file

@ -26,11 +26,23 @@ function getTempFilePath(): string {
return join(tmpdir(), `pi-bash-${id}.log`);
}
/**
* Default timeout applied when the LLM does not specify one.
* Prevents indefinite hangs from long-running processes (dev servers, watchers, etc.)
*/
const DEFAULT_TIMEOUT_SECONDS = 120;
/**
* If no stdout/stderr output is received for this many seconds, kill the process.
* Catches processes that are alive but idle (e.g. a backgrounded server after startup).
*/
const DEFAULT_NO_OUTPUT_TIMEOUT_SECONDS = 30;
const bashSchema = Type.Object({
command: Type.String({ description: "Bash command to execute" }),
timeout: Type.Optional(
Type.Number({
description: "Timeout in seconds (optional, no default timeout)",
description: `Timeout in seconds. Defaults to ${DEFAULT_TIMEOUT_SECONDS}s if not specified. Use a higher value for long-running builds or installations.`,
}),
),
});
@ -62,6 +74,8 @@ export interface BashOperations {
signal?: AbortSignal;
timeout?: number;
env?: NodeJS.ProcessEnv;
/** Called with a function that can kill the process tree. Used by no-output timeout. */
onKillHandle?: (kill: () => void) => void;
},
) => Promise<{ exitCode: number | null }>;
}
@ -70,7 +84,7 @@ export interface BashOperations {
* Default bash operations using local shell
*/
const defaultBashOperations: BashOperations = {
exec: (command, cwd, { onData, signal, timeout, env }) => {
exec: (command, cwd, { onData, signal, timeout, env, onKillHandle }) => {
return new Promise((resolve, reject) => {
const { shell, args } = getShellConfig();
@ -90,6 +104,15 @@ const defaultBashOperations: BashOperations = {
stdio: ["ignore", "pipe", "pipe"],
});
// Expose kill handle for no-output timeout
if (onKillHandle) {
onKillHandle(() => {
if (child.pid) {
killProcessTree(child.pid);
}
});
}
let timedOut = false;
// Set timeout if provided
@ -183,6 +206,10 @@ export interface BashToolOptions {
commandPrefix?: string;
/** Hook to adjust command, cwd, or env before execution */
spawnHook?: BashSpawnHook;
/** Default timeout in seconds when LLM does not specify one. Set to 0 to disable. Default: 120 */
defaultTimeoutSeconds?: number;
/** Kill process if no output received for this many seconds. Set to 0 to disable. Default: 30 */
noOutputTimeoutSeconds?: number;
}
export function createBashTool(
@ -192,11 +219,13 @@ export function createBashTool(
const ops = options?.operations ?? defaultBashOperations;
const commandPrefix = options?.commandPrefix;
const spawnHook = options?.spawnHook;
const configDefaultTimeout = options?.defaultTimeoutSeconds ?? DEFAULT_TIMEOUT_SECONDS;
const configNoOutputTimeout = options?.noOutputTimeoutSeconds ?? DEFAULT_NO_OUTPUT_TIMEOUT_SECONDS;
return {
name: "bash",
label: "bash",
description: `Execute a bash command in the current working directory. Returns stdout and stderr. Output is truncated to last ${DEFAULT_MAX_LINES} lines or ${DEFAULT_MAX_BYTES / 1024}KB (whichever is hit first). If truncated, full output is saved to a temp file. Optionally provide a timeout in seconds.`,
description: `Execute a bash command in the current working directory. Returns stdout and stderr. Output is truncated to last ${DEFAULT_MAX_LINES} lines or ${DEFAULT_MAX_BYTES / 1024}KB (whichever is hit first). If truncated, full output is saved to a temp file. Default timeout is ${configDefaultTimeout}s - provide a higher timeout for long builds or installations.`,
parameters: bashSchema,
execute: async (
_toolCallId: string,
@ -204,6 +233,9 @@ export function createBashTool(
signal?: AbortSignal,
onUpdate?,
) => {
// Apply default timeout when LLM does not specify one
const effectiveTimeout = timeout ?? (configDefaultTimeout > 0 ? configDefaultTimeout : undefined);
// Apply command prefix if configured (e.g., "shopt -s expand_aliases" for alias support)
const resolvedCommand = commandPrefix
? `${commandPrefix}\n${command}`
@ -216,6 +248,21 @@ export function createBashTool(
let tempFileStream: ReturnType<typeof createWriteStream> | undefined;
let totalBytes = 0;
// No-output timeout: kill process if it goes silent
let noOutputTimer: NodeJS.Timeout | undefined;
let noOutputTriggered = false;
// Store kill function to call from no-output timeout
let killFn: (() => void) | undefined;
const resetNoOutputTimer = () => {
if (configNoOutputTimeout <= 0) return;
if (noOutputTimer) clearTimeout(noOutputTimer);
noOutputTimer = setTimeout(() => {
noOutputTriggered = true;
killFn?.();
}, configNoOutputTimeout * 1000);
};
// Keep a rolling buffer of the last chunk for tail truncation
const chunks: Buffer[] = [];
let chunksBytes = 0;
@ -225,6 +272,9 @@ export function createBashTool(
const handleData = (data: Buffer) => {
totalBytes += data.length;
// Reset no-output timer on every chunk of output
resetNoOutputTimer();
// Start writing to temp file once we exceed the threshold
if (totalBytes > DEFAULT_MAX_BYTES && !tempFilePath) {
tempFilePath = getTempFilePath();
@ -265,14 +315,20 @@ export function createBashTool(
}
};
// Start the no-output timer (will fire if command produces no output at all)
resetNoOutputTimer();
ops
.exec(spawnContext.command, spawnContext.cwd, {
onData: handleData,
signal,
timeout,
timeout: effectiveTimeout,
env: spawnContext.env,
onKillHandle: (kill) => { killFn = kill; },
})
.then(({ exitCode }) => {
if (noOutputTimer) clearTimeout(noOutputTimer);
// Close temp file stream
if (tempFileStream) {
tempFileStream.end();
@ -316,6 +372,14 @@ export function createBashTool(
}
}
// If killed by no-output timeout, report it clearly
if (noOutputTriggered) {
if (outputText) outputText += "\n\n";
outputText += `Process was killed after ${configNoOutputTimeout}s of no output. If this is a long-running server or build, use a higher timeout or run the process in the background with '&' and redirect output.`;
reject(new Error(outputText));
return;
}
if (exitCode !== 0 && exitCode !== null) {
outputText += `\n\nCommand exited with code ${exitCode}`;
reject(new Error(outputText));
@ -327,6 +391,8 @@ export function createBashTool(
}
})
.catch((err: Error) => {
if (noOutputTimer) clearTimeout(noOutputTimer);
// Close temp file stream
if (tempFileStream) {
tempFileStream.end();
@ -336,7 +402,11 @@ export function createBashTool(
const fullBuffer = Buffer.concat(chunks);
let output = fullBuffer.toString("utf-8");
if (err.message === "aborted") {
if (noOutputTriggered) {
if (output) output += "\n\n";
output += `Process was killed after ${configNoOutputTimeout}s of no output. If this is a long-running server or build, use a higher timeout or run the process in the background with '&' and redirect output.`;
reject(new Error(output));
} else if (err.message === "aborted") {
if (output) output += "\n\n";
output += "Command aborted";
reject(new Error(output));