This guide gets Koder from install to a useful first coding session.

Use uv tool install for a clean command-line install:

uv tool install koder

For local development from this repository:

uv sync
uv run koder

The shortest setup is a universal API key and a model name:

export KODER_API_KEY="your-api-key"
export KODER_MODEL="gpt-4o"
koder

KODER_API_KEY, KODER_BASE_URL, KODER_MODEL, and KODER_REASONING_EFFORT override provider-specific settings and ~/.koder/config.yaml.

Provider-specific examples:

OPENAI_API_KEY="sk-..." KODER_MODEL="gpt-4o" koder
ANTHROPIC_API_KEY="..." KODER_MODEL="claude-opus-4-20250514" koder
GOOGLE_API_KEY="..." KODER_MODEL="gemini/gemini-2.5-pro" koder
KODER_BASE_URL="http://localhost:8080/v1" KODER_MODEL="openai/local-model" koder

Subscription-backed providers use koder auth:

koder auth login google
koder auth login claude
koder auth login chatgpt
koder auth login antigravity
koder auth list

After login, use the provider prefix in KODER_MODEL, for example google/gemini-3-pro-preview, claude/claude-opus-4-5-20250514, or chatgpt/gpt-5.2.

See Configuration Guide for the full provider matrix.

Interactive mode is the normal daily workflow:

koder

Single prompt mode is useful from scripts or when you already know the task:

koder "summarize the current git diff"

Named sessions keep a durable conversation attached to a project or topic:

koder -s billing-refactor
koder -s billing-refactor "continue the failing test investigation"

Resume previous work with:

koder --resume
koder --continue

Inside a project, run these commands before asking for large edits:

/onboarding
/status
/model
/files
/permissions

They show the active provider, session, workspace directory, loaded context, and permission policy. If something looks wrong, fix it before delegating substantial work.

Try a read-only task first:

koder "inspect this repo and explain the test command"

Then move to a small edit:

koder "fix the failing test in tests/test_example.py and run the focused test"

Koder will use the project instructions from AGENTS.md when present, and it stores session state locally under ~/.koder/.

• Interactive TUI for keyboard controls and slash commands.
• Sessions and Memory for durable context and cleanup.
• Workflows for review, planning, Git, and PR workflows.
• Permissions and Privacy for local data and tool approval behavior.