[Bug]: exec timeouts above the Node timer limit cancel almost immediately

[adenzhou1350]

Product or interface

CLI - headless

Version

Source commit 4401b0edb0e6ad753d3952b75a31ec87807b6aab; Node.js 24.14.1; pnpm 11.7.0.

Platform

Windows x64, OS build 10.0.26200.

Issue area

Other — execution timeout handling.

Steps to reproduce

The headless parser accepts --timeout 2147483648ms and --timeout 600h
because both convert to positive safe integers. The value is forwarded as
policy.timeoutMs, then passed directly to Node's setTimeout:

• Parser
• Headless forwarding
• Final timer

A minimal check of the underlying Node behavior, with no provider or credentials:

const start = performance.now();
setTimeout(() => console.log('unexpected early expiry:', performance.now() - start), 2147483648);

I also tested the complete pinned invocation and coordinator executable bodies
after Node's TypeScript transformation, using real Node timers and a synthetic
conversation port that finishes after 40 ms. The port records abortSession
calls; no model, network, tool or stored session is used. Three repeats each:

Parsed timeout	Coordinator result	Abort reason
2h	succeeded	none
2147483647ms	succeeded	none
2147483648ms	timeout	timeout
600h	timeout	timeout

This is an isolated component reproduction, not a built-CLI, live-provider,
interactive-TUI or ACP acceptance test. No actual 25-day execution is needed.

Expected and actual behavior

Expected: reject unsupported durations before starting a run, or preserve the
requested deadline using bounded timer intervals.

Actual: larger accepted durations cancel the run almost immediately. Node
clamps values above 2147483647 to 1 ms, as documented in
its timer API.
The coordinator separately forwards a deadline about 25 days in the future,
so the immediate local cancellation contradicts that deadline.

This affects unusually large timeout values; ordinary hour-scale controls passed.

Redacted error summary

TimeoutOverflowWarning: 2147483648 does not fit into a 32-bit signed integer.
Timeout duration was set to 1.

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• I have searched existing issues.
• I have included my version and removed sensitive information.