CLI broken (functionality does not work) on Windows: "'charmap' codec can't encode character"

[garretwilson]

Describe the bug

Running the following on Windows (in PowerShell or in Git Bash for Windows) produces a Python character encoding error. This implies that the Python library is assuming a charset rather than specifying wone.

aws agent-toolkit list-available-skills

Regression Issue

• Select this option if this issue appears to be a regression.

Expected Behavior

The command aws agent-toolkit list-available-skills lists skills with no error.

Current Behavior

{
    "skills": [
…
        {
            "name": "amazon-documentdb",
            "description":

aws: [ERROR]: 'charmap' codec can't encode character '\u2192' in position 249: character maps to <undefined>

Reproduction Steps

1. Open PowerShell or Git Bash for Windows on Windows 11.
2. Issue aws agent-toolkit list-available-skills

Possible Solution

There is no known solution at the time. The CLI is completely broken.

Additional Information/Context

See UnicodeEncodeError: 'charmap' codec can't encode characters for possible background research.

This comes up in the AgentCore CLI as well; see aws/agentcore-cli#2010. The stack trace there indicated …\.venv\Lib\site-packages\bedrock_agentcore\runtime\app.py:_sync_stream_with_error_handling:945. There's no way to know without further investigation whether this is some shared AWS Python library, or bad Python Code AWS has duplicated across toolkits and/or CLIs, or what.

CLI version used

aws-cli/2.36.23 Python/3.14.6 Windows/11 exe/AMD64

Environment details (OS name and version, etc.)

Windows 11 Pro 25H2 26200.9168