Tool execution completely broken on Arch Linux WSL — tools emitted as text instead of executed

[kloss-ghd]

Checks

• I have searched github.com/aws/amazon-q-developer-cli/issues and there are no duplicates of my issue
• I have run q doctor in the affected terminal session
• I have run q restart and replicated the issue again

Operating system

Linux 6.6.87.2-microsoft-standard-WSL2 - Arch Linux

Expected behaviour

Kiro should execute tool calls normally when running in Arch Linux under WSL2.

Commands like:

• execute_command
• read_file
• write_file

should invoke the actual tool runtime and return real filesystem/shell results.

For example, when prompted:
"Read proof.txt and reply with only its contents."

Kiro should actually read the file from the current working directory and return the file contents.

Actual behaviour

Kiro does not execute any tools.

Instead, it emits <tool_use> blocks as plain text and appears to hallucinate filesystem results.

Example:

<tool_use>
{"name": "read_file", "arguments": {"file_path": "/home/kloss/proof.txt"}}
</tool_use>

The file /home/kloss/proof.txt doesn't exist.

The tool was never actually executed.

The assistant also incorrectly checks paths that do not match the current working directory.

This affects:

• execute_command
• read_file
• write_file

and likely all tool execution.

Steps to reproduce

1. Run Arch Linux under WSL2
2. Install Kiro CLI
3. Run:
   kiro-cli doctor

Doctor reports:
"Everything looks good!"

4. Enable inline mode:
   kiro-cli inline enable

5. Create a test directory:
   mkdir -p /tmp/kiro-proof
   cd /tmp/kiro-proof
   echo "UNIQUE_KIRO_TEST_93817" > proof.txt

6. Start Kiro:
   kiro-cli chat --trust-all-tools

7. Prompt:
   Read proof.txt and reply with only its contents.

8. Observe that Kiro outputs fake <tool_use> blocks instead of executing tools.

Environment

<This will be visible to anyone. Do not include personal or sensitive information>

[q-details]
version = "2.4.1"
hash = "937fa9a6ff55382dd599408c80bb4b87517146ad"
date = "2026-05-21T03:37:56.378129Z (5d ago)"
variant = "minimal"

OS: Arch Linux (WSL2)
Shell: [your shell here, e.g. zsh/bash/fish]
WSL version: WSL2
Inline mode: enabled
Issue reproducible: always

This appears to be a tool runtime/bridge failure where the model falls back to simulated tool-call output instead of actual execution.
[system-info]
chip = "12th Gen Intel(R) Core(TM) i5-1235U"
total-cores = 6
memory = "7.60 GB"

[system-info.os.linux]
kernel_version = "6.6.87.2-microsoft-standard-WSL2"
id = "arch"
name = "Arch Linux"
pretty_name = "Arch Linux"
build_id = "rolling"

[environment]
cwd = "/tmp/kiro-proof"
cli-path = "/tmp/kiro-proof"
os = "Linux"
shell-path = "/usr/bin/zsh"
shell-version = "5.9"
install-method = "unknown"
in-wsl = true

[env-vars]
DISPLAY = ":0"
PATH = "/home/USER/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/usr/lib/wsl/lib:/mnt/c/WINDOWS/system32:/mnt/c/WINDOWS:/mnt/c/WINDOWS/System32/Wbem:/mnt/c/WINDOWS/System32/WindowsPowerShell/v1.0/:/mnt/c/WINDOWS/System32/OpenSSH/:/mnt/c/Users/gkloss/AppData/Local/Programs/Python/Launcher/:/mnt/c/Users/gkloss/AppData/Local/Microsoft/WindowsApps:/mnt/c/Users/gkloss/AppData/Local/Programs/Microsoft VS Code/bin:/mnt/c/Users/gkloss/AppData/Local/Programs/Kiro/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl:/home/USER/.local/bin"
QTERM_SESSION_ID = "30b8d900fdeb4c1c994dd68532f75155"
Q_SET_PARENT_CHECK = "1"
Q_TERM = "2.4.1"
SHELL = "/usr/bin/zsh"
TERM = "xterm-256color"

[kloss-ghd]

Update: Kiro Classic works.

Running:

kiro-cli --classic

allows tools to execute correctly.

The issue appears specific to the new Kiro CLI UX/TUI. In the new UX, tool calls are printed as raw <tool_use> text instead of being intercepted/executed. In classic mode, the same commands work.

So this is likely a regression in the new CLI UX tool execution bridge, possibly WSL/PTY-related.