Bug: PingResponse.from_dict crashes with ValueError when CLI returns ISO-8601 timestamp (macOS arm64 wheel, SDK 0.3.0 + CLI 1.0.51)

[awilliams88]

Summary

PingResponse.from_dict raises a ValueError on macOS (arm64) when the bundled Copilot CLI binary (1.0.51) returns an ISO-8601 string for the timestamp field in the ping JSON-RPC response, because the SDK unconditionally parses it with int(timestamp).

---

Environment

Property	Value
SDK version	github-copilot-sdk 0.3.0
Platform	macOS arm64 (Apple Silicon)
Python version	3.13
Bundled CLI version	1.0.51 (from copilot/bin/copilot --version)
copilot/bin/VERSION file	1.0.36-0

---

Steps to Reproduce

1. Install the SDK on macOS arm64:

   pip install github-copilot-sdk==0.3.0

2. Start the bundled CLI server and connect a CopilotClient using ExternalServerConfig — it will call client.start() which internally calls ping().

---

Error

ValueError: invalid literal for int() with base 10: '2026-05-22T17:50:31.689Z'

Points to copilot/client.py line 204:

return PingResponse(str(message), int(timestamp), int(protocolVersion))

---

Root Cause

The macOS arm64 wheel of github-copilot-sdk 0.3.0 bundles CLI binary 1.0.51. This binary now returns the ping response's timestamp as an ISO-8601 string instead of a Unix millisecond integer. int(timestamp) raises ValueError on an ISO-8601 string.

The Linux/amd64 wheel is unaffected — it bundles a different binary build that still returns an integer, so no crash occurs there.

---

Suggested Fix

def _parse_timestamp(value: object) -> int:
    try:
        return int(value)  # type: ignore[arg-type]
    except (ValueError, TypeError):
        from datetime import datetime, timezone
        dt = datetime.fromisoformat(str(value).replace("Z", "+00:00"))
        return int(dt.timestamp() * 1000)

# In PingResponse.from_dict:
return PingResponse(str(message), _parse_timestamp(timestamp), int(protocolVersion))

Note: timestamp is only consumed by _verify_protocol_version which only reads protocolVersion, so a lenient parse here is completely safe.

[github-actions]

Investigation Findings

Thanks for the detailed report! I investigated the relevant code path in the current main branch.

Files examined: python/copilot/client.py (lines 308–331), python/copilot/generated/rpc.py (lines 75–76)

Finding: This behavior is already handled in the current codebase.

The code at client.py lines 326–331 already handles both integer Unix-ms timestamps and ISO-8601 string timestamps:

timestamp_value = (
    datetime.fromtimestamp(timestamp / 1000, tz=UTC)
    if isinstance(timestamp, (int, float))
    else from_datetime(timestamp)  # uses dateutil.parser.parse for ISO-8601 strings
)
return PingResponse(str(message), timestamp_value, int(protocol_version))

The from_datetime fallback calls dateutil.parser.parse(x), which correctly handles ISO-8601 strings like 2026-05-22T17:50:31.689Z.

The int(timestamp) at line 204 you referenced no longer exists in the current code — it appears the issue was already addressed in a prior commit.

Reclassified as question: The behavior described is not present in the current SDK. If you're still seeing this crash, please verify you're running the latest published SDK version or building from main.

Generated by Bug Handler for issue #1383 · ● 2.7M · ◷

[awilliams88]

I was able to isolate this further and can now provide a minimal reproducible case.

Failing environment

• macOS (Apple Silicon / arm64)
• Python 3.13.5
• github-copilot-sdk==0.3.0

Working environment

• Ubuntu x86_64 VPS
• Python 3.14.5
• github-copilot-sdk==0.3.0

So this does not appear to be a Python SDK version mismatch.

Minimal reproduction

Start bundled CLI server:

python -c "import copilot, os; print(os.path.join(os.path.dirname(copilot.__file__), 'bin', 'copilot'))"
# then run the printed binary with:
# <printed_path> --server --port 9000

Then run:

from copilot import CopilotClient, ExternalServerConfig
import asyncio

async def main():
    client = CopilotClient(
        ExternalServerConfig(url="http://127.0.0.1:9000")
    )
    await client.start()

asyncio.run(main())

Actual traceback

Traceback (most recent call last):
  File ".../site-packages/copilot/client.py", line 1053, in start
    await self._verify_protocol_version()
  File ".../site-packages/copilot/client.py", line 2149, in _verify_protocol_version
    ping_result = await self.ping()
  File ".../site-packages/copilot/client.py", line 1787, in ping
    return PingResponse.from_dict(result)
  File ".../site-packages/copilot/client.py", line 204, in from_dict
    return PingResponse(str(message), int(timestamp), int(protocolVersion))
ValueError: invalid literal for int() with base 10: '2026-05-23T13:51:42.190Z'

Root cause hypothesis

It looks like the SDK expects:

{
  "timestamp": 1748008302
}

but the macOS bundled CLI returns:

{
  "timestamp": "2026-05-23T13:51:42.190Z"
}

So this line fails:

int(timestamp)

Ubuntu x86_64 with the same SDK version does not exhibit this issue, suggesting the bundled platform-specific CLI is returning different ping response formats.