UnicodeEncodeError crashes `setup` on Windows before any work starts (logo uses Unicode block chars on cp1252 console)

[lenintorresact]

Analysis below was done by Claude (Anthropic, via Claude Code) while debugging this on my machine. Filing as-is — not claiming credit for the investigation.

What happened?

On a fresh Windows 11 install, uvx google-agents-cli setup crashes with UnicodeEncodeError: 'charmap' codec can't encode characters in position 1-3 before reaching any setup logic. The crash happens inside _print_logo() at setup/cmd_setup.py:41 because the logo is drawn with Unicode block characters (█ ▀ ▄, U+2588 / U+2580 / U+2584), and Python on Windows defaults to writing stdout through the legacy cp1252 codepage, which has no glyphs for those characters.

This is independent of #14. After working around #14 (or installing without gcloud needing to be called), this bug still prevents setup from running unless the user happens to know to set PYTHONUTF8=1. For a "getting started" command, that's a hard wall on Windows.

Steps to Reproduce

1. Fresh Windows 11 PowerShell session, no PYTHONUTF8 set.
2. uvx google-agents-cli setup
3. Crash before the logo prints, before any setup work begins.

What did you expect to happen?

setup should print the logo (or a non-fancy fallback) and proceed.

Workaround

$env:PYTHONUTF8 = "1"
uvx google-agents-cli setup

or permanently: [Environment]::SetEnvironmentVariable("PYTHONUTF8", "1", "User").

Suggested fix

Two options, in order of preference:

1. Reconfigure stdio at CLI entry. Near the top of main.py, before any click.secho runs:

import sys
if sys.platform == "win32":
    sys.stdout.reconfigure(encoding="utf-8", errors="replace")
    sys.stderr.reconfigure(encoding="utf-8", errors="replace")

This fixes the logo and any future Unicode-bearing output. The codebase already prints non-ASCII characters in other places (e.g. the ⚠️ warning emoji at auth.py:67, ─ separators throughout) that would crash the same way on a cp1252 console.

2. Guard _print_logo with a try/except + ASCII fallback. Less robust — only protects this one site, leaves the other Unicode call sites as latent crashes.

Stack trace

agents-cli v0.1.3
Traceback (most recent call last):
  File "...\google\agents\cli\setup\cmd_setup.py", line 41, in _print_logo
    click.secho(
        " █▀█ █▀▀ █▀▀ █▄ █ ▀█▀ █▀   █▀▀ █  █",
        fg="blue",
        bold=True,
    )
  File "...\click\termui.py", line 698, in secho
    return echo(message, file=file, nl=nl, err=err, color=color)
  File "...\click\utils.py", line 324, in echo
    file.write(out)
  File "...\Lib\encodings\cp1252.py", line 19, in encode
    return codecs.charmap_encode(input, self.errors, encoding_table)[0]
UnicodeEncodeError: 'charmap' codec can't encode characters in position 1-3: character maps to <undefined>

Client information

• CLI: agents-cli v0.1.3
• OS: Windows 11 (10.0.26200)
• Python: 3.14 (uvx-managed)
• Console: PowerShell 5.1, default cp1252 codepage
• Install: uvx google-agents-cli setup