Terminal Coding Agent (Baxter CLI)

A local terminal coding assistant with provider switching, tool-calling, and safety rails for file + command operations.

Features

• Interactive chat loop with tool chaining
• Provider support:
  • anthropic (/v1/messages)
  • openai (/v1/responses)
  • groq (OpenAI-compatible chat/completions)
• Startup provider preference: anthropic -> openai -> groq
• Curated model lists per provider (with OpenAI dynamic filtering against /v1/models)
• Working indicator while model calls are in flight (Baxter is working...)
• Built-in malformed tool-call recovery (one automatic retry if JSON tool call is broken)

Current Model Sets

• anthropic
  • claude-opus-4-6
  • claude-sonnet-4-6
  • claude-haiku-4-5-20251001 (default)
• openai
  • gpt-4o-mini (default)
  • gpt-5-mini
  • codex-3.5
• groq
  • llama-3.1-8b-instant (default)

Notes:

• OpenAI model IDs are fetched from /v1/models and intersected with the allowlist above.
• You can override the OpenAI allowlist with OPENAI_MODELS_ALLOWLIST (comma-separated IDs).

Tooling

Tools available:

• read_file
• write_file
• apply_diff
• list_dir
• make_dir
• delete_path
• run_cmd
• git_cmd
• search_code

Key behaviors:

• File paths are restricted to the repo root (no absolute paths, no .. escape).
• delete_path supports recursive directory deletion (default recursive=true).
• write_file refuses to overwrite existing files unless overwrite=true.
• apply_diff supports targeted edits using exact find/replace with optional replace_all=true.
• apply_diff returns a unified diff summary (+/-) and stores the full last diff for terminal viewing.

Confirmations

Baxter asks y/N confirmation before:

• delete_path
• apply_diff
• write_file when overwrite=true
• git push
• git rm

CLI Commands

• / opens interactive provider/model picker
• /providers (alias: /settings)
• /provider <groq|openai|anthropic>
• /models
• /model <model_name>
• /lastdiff (expand the last apply_diff unified diff)
• /help

Project Layout

.
├─ .env.example
├─ pyproject.toml
├─ README.md
└─ baxter/
   ├─ __init__.py
   ├─ baxter_cli.py
   ├─ providers.py
   └─ tools/
      ├─ __init__.py
      ├─ registry.py
      ├─ safe_path.py
      ├─ read_file.py
      ├─ write_file.py
      ├─ apply_diff.py
      ├─ list_dir.py
      ├─ make_dir.py
      ├─ delete_path.py
      ├─ run_cmd.py
      ├─ git_cmd.py
      └─ search_code.py

Requirements

• Python 3.10+
• At least one API key:
  • ANTHROPIC_API_KEY
  • OPENAI_API_KEY
  • GROQ_API_KEY

Setup (Developer)

1. Create and activate a virtual environment.

Windows (cmd):

python -m venv .venv
.venv\Scripts\activate.bat

Windows (PowerShell):

python -m venv .venv
.venv\Scripts\Activate.ps1

macOS/Linux:

python3 -m venv .venv
source .venv/bin/activate

2. Install editable:

pip install -e .

3. Create .env from .env.example and set keys:

GROQ_API_KEY=...
OPENAI_API_KEY=...
ANTHROPIC_API_KEY=...
# optional:
# OPENAI_MODELS_ALLOWLIST=gpt-4o-mini,gpt-5-mini,codex-3.5

The CLI also loads user-level keys from ~/.baxter/.env first, then applies project .env as an override.

Setup (User install via pip)

1. Install Baxter:

pip install baxter-cli

2. Configure keys once per machine in:

• Windows: %USERPROFILE%\.baxter\.env
• macOS/Linux: ~/.baxter/.env

Example:

GROQ_API_KEY=...
OPENAI_API_KEY=...
ANTHROPIC_API_KEY=...
# optional:
# OPENAI_MODELS_ALLOWLIST=gpt-4o-mini,gpt-5-mini,codex-3.5

If keys are missing on startup, Baxter now offers an interactive one-time setup prompt and writes keys to ~/.baxter/.env.

3. Open any project folder and run:

baxter

Environment Setup Smoke Test

Use this to verify first-run key loading and precedence.

1. Missing keys path:

Remove-Item Env:OPENAI_API_KEY -ErrorAction SilentlyContinue
Remove-Item Env:ANTHROPIC_API_KEY -ErrorAction SilentlyContinue
Remove-Item Env:GROQ_API_KEY -ErrorAction SilentlyContinue
Remove-Item "$HOME\.baxter\.env" -ErrorAction SilentlyContinue
baxter

Expected: startup warning about missing keys.

2. User-level key file path:

mkdir $HOME\.baxter -Force
@"
OPENAI_API_KEY=your_real_key
"@ | Set-Content "$HOME\.baxter\.env"
baxter

Expected: no missing-key warning.

3. Project-level override path:

@"
GROQ_API_KEY=your_real_groq_key
"@ | Set-Content ".env"
baxter

Expected: local .env values override user-level values for overlapping keys.

Run

baxter

or:

python -m baxter.baxter_cli

Command Safety Model

run_cmd allowlist:

• python
• python3
• pip
• pip3
• git

git_cmd subcommand allowlist:

• status
• log
• diff
• show
• branch
• switch
• checkout
• add
• commit
• push
• pull
• fetch
• remote
• rev-parse
• restore
• rm
• mv
• stash

Additional protections:

• No shell execution for command tools
• Path traversal/root escape blocked
• Selected risky git flags blocked (--git-dir, --work-tree, -C, etc.)
• Per-tool timeout bounds

Troubleshooting

• Missing key error:
  • Verify .env has the expected API key and restart Baxter.
• OpenAI tool-call/JSON issues:
  • Baxter now does one automatic repair retry for malformed tool-call JSON.
• OpenAI model list too large:
  • Set OPENAI_MODELS_ALLOWLIST explicitly.
• git not found on PATH:
  • Install Git and restart terminal.