Get started with Koder

Koder is aixplain's AI coding agent for your desktop and terminal. Describe the change you want in plain language, and Koder reads your code, makes edits you review line by line, runs your tests and asks before anything risky. This article explains how to start a task, plan before you build, review and commit changes, connect the model you want, extend Koder with MCP servers, skills and plugins, use it from the terminal and in CI and what it can't do yet.

What is Koder?

Koder is a model connected to your project through tools it can use, permissions it has to follow and a history it carries from one step to the next. It can search and read files, edit code and run commands and tests. It uses what it learns from each result in the next step.

You follow every step, answer its questions, stop it at any time and review the diff before you keep anything. Your sessions and settings stay on your computer.

Key capabilities

• Desktop and terminal: the same agent, permissions and sessions in the aixplain desktop app and in a terminal app, plus a koder CLI for scripts and CI.
• Plan first: a planning agent thinks a change through before any code changes.
• Review and diffs: every change in a session collected in one diff, unified or split, ready to commit.
• Sessions across projects: one sidebar for every project's sessions, with what is running or waiting on you at the top.
• Your choice of model: aixplain models, a Claude, ChatGPT or Cursor plan you already pay for, your own provider or a local model.
• Extensions: project instructions in AGENTS.md, MCP servers, skills and plugins.

To find likely security bugs in a repository, see Find security issues with Scan.

Install Koder

Koder comes with the aixplain desktop app. Download it from aixplain.com/koder and open aixplain. For every installer and the steps for each computer, see Get started with aixplain Desktop.

The first time Koder runs, it asks you to sign in to aixplain. Signing up is free, with no card needed. Then pick a model in the model picker.

Install the CLI

To use Koder in your terminal instead, or as well, install the koder CLI. It runs on macOS (arm64 and x64), Linux (arm64 and x64) and Windows x64.

On macOS and Linux:

curl -fsSL https://github.com/aixplain/koder/releases/latest/download/install | bash

On Windows, in PowerShell:

irm https://github.com/aixplain/koder/releases/latest/download/install.ps1 | iex

The installer places koder in ~/.koder/bin and adds it to your user PATH. Open a new terminal after installation.

Start a task

1. Open the desktop app and select Koder.
2. Open a project folder.
3. Describe a task in plain language, or pick a starter.
4. Follow the steps, answer its questions and stop it at any time.

The starters are: explain this project, find and fix a bug, add a feature, write tests, review my changes or start from a pull request.

Give Koder a concrete task. Say what done looks like and any constraints, then follow the steps and review the diff.

Example requests

• "Explain this project."
• "Find why this test fails, explain the cause, make the smallest fix and run the relevant tests."
• "Add a CSV export to the reports page and write tests for it."
• "Review my changes before I open a pull request."

Plan before you build

To think a change through before any code changes, ask Koder to plan first. The planning agent works out the approach, and you let it build once the plan looks right.

In the terminal, koder run --agent plan "<your task>" does the same from the shell.

Review and commit changes

The Review panel gathers everything the session changed, so you can read it before you commit.

1. Open the Review panel.
2. Read the diff, unified or split.
3. Commit from the app when you are happy with the changes.

Work with source control

Connect GitHub, GitLab, Forgejo or Gitea, Bitbucket or Azure DevOps to work with your repositories from the app.

• Clone and publish: clone a repository, or publish a project as a new one.
• Pull requests: open a pull request, or start a chat from one with its review comments.
• Worktrees: work in one worktree per chat, so chats don't change each other's files.

Find your sessions

The sidebar holds the sessions from all your projects. Anything running or waiting on you sits at the top with a short status such as "running 4m" or "waiting for you". The rest can be grouped by date or by project, or narrowed to one project.

Archived chats can be reopened from Find a chat → Archived. To bring sessions from a share file or another coding agent, run koder import.

Use your Claude, ChatGPT or Cursor plan

If you already pay for Claude, ChatGPT or Cursor, you can use that plan in Koder. Koder runs each vendor's own CLI with the sign-in you already have, so there are no new keys to manage.

1. Install the vendor's CLI from the table above, on the same computer as Koder.
2. Sign in to it with your plan's account.
3. Open Koder. It finds installed CLIs automatically, including ones behind version managers.
4. Pick the plan's model in the model picker.

To check where each plan stands, open Settings → Models & providers → Your subscriptions, or run koder providers subs. Each plan shows as Ready, Not signed in or Not installed, with your account and plan, and the one command that fixes it.

Usage on a connected plan counts against that plan's limits, not your aixplain credits. The usage page shows your Koder, Claude Code and Codex usage together, with your plan limits. Each limit window says whether you are ahead of it, behind it or on pace. Which models you can pick depends on what your plan offers.

Extend Koder

You can extend Koder with project instructions, MCP servers, skills and plugins, in the desktop app and the koder CLI. Workspace trust decides which projects' own configuration Koder honors.

Give a project its instructions

Put instructions that every session in a project should follow in an AGENTS.md file in your repository. Use it for the things you'd otherwise repeat in every chat, such as how to run the tests or which conventions to follow.

Add MCP servers

Add and remove MCP servers from the desktop app, or manage them in the terminal with koder mcp.

• Permissions apply: in Ask first, MCP actions ask before they run, like any other change.
• Large catalogs: when your MCP servers expose many tools, Koder searches them on demand instead of sending every tool's description on every request.
• Hung servers: MCP tool calls are limited to 5 minutes by default, so a server that stops answering can't stall a turn.

Koder can also act as an MCP server, so other agents can start and read Koder sessions. Each one signs in with a pairing code and gets a scope it can never exceed: read only, ask, auto or full. The server holds each client to its scope.

Create and install skills

A skill gives Koder reusable instructions for a kind of task.

1. In the desktop app, describe the skill you want.
2. Koder drafts the skill, checks it and saves it.
3. Try it before saving, or share it with your aixplain workspace.

You can also start from an uploaded SKILL.md. In the terminal, koder skill creates, checks, browses and installs skills. Skills shared with your aixplain workspace are available in Omni too.

Add plugins

Add plugins to extend Koder. A project's configuration must pin each plugin to a version. Your own user configuration can leave a version unpinned, and Koder warns you when it does.

Choose which projects to trust

Use koder trust to choose the directories that may contribute configuration. Trust follows the real path of a folder. In a folder you haven't trusted:

• Opening the repository can't turn off the sandbox.
• Browser control and device control are ignored.

Use Koder in the terminal

The Koder terminal app has the same agent, permissions and sessions as the desktop app, with keyboard and mouse control.

• Inline diffs: edits show as diffs in the conversation.
• A side panel: tracks context, spend, changed files and tool use.
• Offline highlighting: code is highlighted without downloading anything while it runs.
• Steering: steer a running turn with Ctrl + O without stopping its background commands. Stop and Esc still stop them.
• Pull request checks: /pr watches a pull request's checks and wakes the chat when they pass or fail, when the pull request is merged or closed, or when new comments arrive.

Sign in and start a session

1. Open a terminal in your project folder.
2. Run koder login to sign in to aixplain, and koder whoami to check the account.
3. Run koder models to see the models you can use.
4. Run koder to open the terminal app in the current project.
5. Describe a task, follow the steps and review the diff.

cd your-project
koder login
koder

Set how much Koder does on its own

Switch autonomy with /auto followed by a level: ask, rules, read-only, auto or full.

• ask: commands, file changes and network calls wait for your approval.
• rules: follows your permission rules only. The default rules allow commands and edits.
• auto: works on its own within Auto's limits. When it refuses something, such as a push, it says what is outside Auto and how to allow it.
• full: works without asking, with the exceptions below.

Run koder inspect to see the effective permission policy and which layer set each value.

Commands

Run koder --help or koder <command> --help for every command and option in your installed version.

koder serve bound to anything other than your own machine (a non-loopback address) needs a password of at least 12 characters.

Where Koder keeps its files

XDG environment settings can change these paths.

Update the CLI

koder upgrade
koder --version

Upgrading keeps your sessions, saved permissions, schedules and theme. The aixplain-code command remains available as a compatibility alias. The desktop app checks for updates itself.

Run Koder in CI

koder run takes a prompt from the shell, so you can run the agent in scripts and CI. It waits for background work to finish before it exits.

koder run "Explain this project"
koder run --agent plan "Plan how to add a CSV export to the reports page"
koder run --model <provider/model> "Summarize the changes on this branch"

• A supported runner: one of the CLI platforms, with curl and bash on macOS and Linux, or PowerShell on Windows.
• A model the job can use: set it up as you would on your computer, with aixplain models, your own provider or a local model.
• Install in the job: use the install commands above. A CI step that runs in the same shell may not see the new PATH, so call ~/.koder/bin/koder directly or add that folder to the job's PATH.
• Pin a version: download the installer from that release's page on GitHub instead of latest.
• Check the job: run koder doctor to check the install, config and providers, and koder inspect to see the effective permission policy.

Pricing and usage

Koder is free to download. What you pay depends on the model:

• aixplain models draw on your team's credits. One credit is one US dollar.
• A connected Claude, ChatGPT or Cursor plan counts against that plan's limits.
• Your own provider bills you directly.
• Local models cost nothing beyond your hardware.

The Core plan costs $0 a month and includes access to Koder. For plans, see Pricing and Account, plans and billing.

Privacy and data

• Stored on your computer: your projects, sessions and settings stay on your machine.
• Sent to the model you choose: the parts of your code a task needs go only to the selected model. Pick a local model or a zero data retention model when that matters.
• Secret files ask first: files such as .env always ask before they are read, in every mode.
• Crash reports: off by default, and they never include your code.

For more, see Privacy and data.

Limitations

• Hosted models, connected apps and sign-in need a network connection.
• The desktop app isn't available for Linux on Arm yet. The CLI and terminal app are.
• A Claude, ChatGPT or Cursor plan needs that vendor's CLI installed and signed in on the same computer.
• This article doesn't list every flag or each CI system's own setup. Run koder <command> --help for the options in your installed version.

Frequently asked questions

Get help

• Fix a problem: see aixplain Desktop troubleshooting, or run koder doctor to check the install, config, providers and recent logs.
• Report a bug: open an issue on GitHub with your version, operating system, the steps to reproduce it and what you expected. koder report saves a bug report with the session, recent logs and version.
• Report a security issue: email care@aixplain.com.
• See what changed: read the release notes.