Bug: Tool server fails to start with empty port argument (v0.8.2)

[limen96]

Describe the bug

When running a penetration test, the tool server inside the Docker sandbox container fails to initialize with the error:

tool_server.py: error: argument --port: invalid int value: ''

The port argument is being passed as an empty string to the tool server.

Steps to reproduce

1. Install Strix v0.8.2 on Kali Linux
2. Pull sandbox image: ghcr.io/usestrix/strix-sandbox:0.1.12
3. Run: strix -t https://example.com -m quick
4. Container starts, Caido proxy initializes successfully, but tool server fails

Expected behavior

Tool server should start with a valid port number.

Logs

Starting tool server...
ERROR: Tool server failed to become healthy
=== Tool server log ===
usage: tool_server.py [-h] --token TOKEN [--host HOST] --port PORT [--timeout TIMEOUT]
tool_server.py: error: argument --port: invalid int value: ''

Environment

• OS: Kali Linux (Linux 6.18.9+kali-amd64 x86_64)
• Docker: 27.5.1+dfsg4
• Strix: 0.8.2
• Sandbox image: ghcr.io/usestrix/strix-sandbox:0.1.12 (9.01GB)
• LLM: OpenRouter (nvidia/nemotron-nano-9b-v2:free)
• CPUs: 28, RAM: 31GB

Additional context

The Caido proxy initializes correctly on port 48080. The issue is specifically with the tool server not receiving the port number.

[Sagar00t]

Hello,

I have exactly the same issue.

Regards,

Saga

[JiwaniZakir]

The error invalid int value: '' means the --port argument is being constructed and passed to tool_server.py as a literal empty string rather than omitted or populated — so the subprocess invocation likely looks something like ["--port", some_variable] where some_variable resolved to "". The root cause is probably that the port assignment for the tool server (distinct from Caido's port 48080) is failing silently before the subprocess is launched — worth checking whatever function in the host-side orchestration code builds the tool server command for a code path where a port variable is set conditionally but falls through without a value. Since Caido initializes successfully, this points specifically to the tool server port allocation logic, not a broader networking or Docker issue.