Start with a tool you already use, then compare it with one that fits a gap in your work. Give both the same small bug, project rules, and test commands. Ask for a focused code change and test results. A developer should review the change before accepting it.
For work in your current IDE, consider GitHub Copilot or Junie. An IDE is an editor with tools for building and testing code. For terminal work, compare Claude Code and Codex. For more choice over the model provider, look at Cline and OpenCode.
This guide covers 12 tools using official documentation checked on 5 October 2026. We have not tested them on the same project. The choices below reflect their documented features, not measured performance. The trial and scorecard are a method you can use yourself.
Compare 12 AI coding agents by how you work
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| Agent | Consider it when you want to… | Check first |
|---|---|---|
| GitHub Copilot | Work in your IDE or hand a task to GitHub's cloud agent | Which mode you will test and what your team allows |
| Cursor | Try an editor built around agent work | Your extensions, debugger, and review process |
| JetBrains Junie | Keep working in a JetBrains IDE | IDE support and Ask versus Code mode |
| Kiro | Agree on requirements and a design before coding | Whether the task needs a written spec |
| Cline | Choose how you connect to a model | Tool approval settings in the app you use |
| Claude Code | Read, edit, and test code through terminal commands | Command permissions and account access |
| OpenAI Codex | Write, review, or debug code across several interfaces | The interface, working environment, and permissions |
| Gemini CLI | Use an open-source Gemini agent in the terminal | Sign-in method, version, and usage limits |
| Aider | Pair in the terminal with built-in Git handling | Automatic commits and pre-commit checks |
| OpenCode | Choose a provider and plan before making changes | Model connection, permissions, and provider costs |
| Devin | Hand over a clear task in a separate workspace | Whether that workspace can build and test your project |
| Amp | Continue work on a remote machine | Model access and remote-machine costs |
Several tools work in more than one place. The groups below show a useful way to start, rather than a full feature list.
Agents to try in your editor
1. GitHub Copilot: use your current IDE
Copilot's IDE agent mode can choose files, edit code, and run commands. You approve commands by default, though your settings or an administrator can allow some to run automatically.
The Copilot cloud agent works in a separate GitHub Actions environment. It can change code on a branch and prepare a pull request. It can only change one repository per task.
Try it if: you want to keep your current IDE or GitHub review process. Record which mode you test. Access to local files and services may differ from the cloud setup.
2. Cursor: test the editor as well as the agent
Cursor Agent can search your project, edit files, and run terminal commands. Its checkpoints let you restore agent changes. They are separate from Git, so keep using normal version control.
Try it if: you are open to changing editors. Use a task that touches several files. Check how easy it is to follow the work, give feedback, and review the final changes. Also check the extensions and debugger you rely on.
3. JetBrains Junie: stay in JetBrains
Junie has two useful modes. Ask mode explores the project without changing its files. Code mode can edit files, run commands, and test changes.
Try it if: your team uses JetBrains IDEs. Ask Junie to explain the affected code, then switch to Code mode for the fix. Check whether the explanation helps you review the result. Confirm support for your IDE version and account before the trial.
4. Kiro: turn requirements into a written plan
Kiro's specs connect requirements or bug analysis with a design and coding tasks. A spec is a written description of what the change should do and how to build it.
Try it if: unclear requirements often lead to rework. For example, plan a feature that restores deleted records. Decide who can restore them and what happens when related data is missing.
Review those decisions before coding. Then check whether the code follows them. For a small fix, include the planning time when you compare tools.
5. Cline: check model choice and approvals
Cline works in editors and the terminal. It supports several ways to access models, including your own provider credentials.
Try it if: choosing the model connection matters to you. Check the settings of the specific app and version you install.
The documentation has a difference worth checking. Cline's overview describes approval for every action. Its CLI README says tool calls run without approval by default. It gives --auto-approve false as the option to require review. Do not assume every Cline interface uses the same defaults.
Agents to try in the terminal
6. Claude Code: use your project commands
Claude Code reads files, edits code, and runs commands. It works in the terminal, IDE, desktop app, and browser.
Try it if: you already use the terminal to investigate bugs. Give it your real build and test commands, plus the repository's rules. Check whether it finds the cause and runs the right tests.
Record its permission settings and how your account connects to the model. Keep these settings in your trial notes so you can repeat the test.
7. OpenAI Codex: choose a specific setup
OpenAI Codex helps write, review, and debug code. OpenAI documents IDE, command-line, and web interfaces, among other options.
Try it if: you want to guide a code change and check the result through one of these interfaces. Record which one you use and where the code runs. A local project and a remote environment may have access to different services.
Give Codex the expected behavior and test commands. Ask it to list completed checks and anything it could not test. Read the code changes yourself before accepting them.
8. Gemini CLI: try a Gemini terminal workflow
Gemini CLI is an open-source terminal agent. It can inspect and edit code, use tools, and run scripted tasks. Its documentation covers sign-in options and stable, preview, and nightly releases.
Try it if: you want a Gemini-based terminal tool whose source code you can inspect. Keep the release channel fixed during your comparison. Record the version, model, and any extensions.
Check the limits for your sign-in method. Access to the application's source code does not mean unlimited model use.
9. Aider: decide how the agent should use Git
Aider's Git guide describes automatic commits. Aider can also commit existing edits before making its own changes.
Try it if: you want a terminal tool that manages a history of its changes. Start with a separate, clean copy of the project. Decide whether you want automatic commits before the agent starts.
Aider skips pre-commit hooks by default. These are checks that a project can run before saving a commit. The guide documents --git-commit-verify to run them. If your team relies on those checks, enable them or run the required checks separately.
10. OpenCode: choose the model provider
OpenCode offers a Plan mode for proposing work before switching to Build mode. Its provider guide explains connections to model services and local models.
Try it if: you want provider choice and a clear planning step. Where possible, keep the model fixed while comparing agent tools. If you change both at once, record that difference.
Check tool permissions and model costs separately. A free application can still connect to a paid model service.
Agents for work you want to hand off
11. Devin: check the workspace first
Devin provides a workspace with a shell, code editor, and browser. You can follow its work and take over when needed.
Try it if: you have a clear ticket that needs few extra decisions. First check that the workspace can install dependencies and run the test that shows the bug.
Count setup and clarification time in your result. If a required service is missing, record the task as blocked until you can check the code properly.
12. Amp: continue work remotely
Amp offers a CLI and remote machines called orbs. An orb holds the code and tools for a conversation, so work can continue after you close your laptop.
Try it if: you want to hand over a small task and return later. Check whether you can understand what happened and review the changes without asking the agent to explain everything again.
Check Amp's pricing for your model connection and orb use. Record both in the trial, even if you use an existing subscription for model access.
Compare the cost of a finished change
A monthly price tells you only part of the cost. Include model usage, remote-machine time, and your own work to prepare, review, and fix the result.
These examples were checked on 5 October 2026. They show billing differences, not a full price comparison.
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| Example | Documented cost pattern | What to record |
|---|---|---|
| Cursor Pro | $20 per month before tax, with included model usage | Selected models, usage limits, and extra charges |
| Copilot cloud agent | Uses AI credits and GitHub Actions minutes | How much of each allowance the task uses |
| OpenCode providers | You can connect a model service | Any provider charges for that connection |
| Amp Hobby | Free product tier; pay-as-you-go orbs and model access through supported subscriptions or keys | Model costs and remote-machine use |
Check the current plan before buying. Record usage even when it fits inside your allowance and adds nothing to this month's bill.
Keep two time totals: your active time and total elapsed time. Active time includes setup, instructions, review, and repairs. Elapsed time runs from the start until the change is ready. A tool may improve one without improving the other.
Test two agents on the same bug
Use one task to learn the setup. Then compare more than one real issue before choosing a tool for your team.
Keep the trial fair
- Choose a small, clear issue. Write down the expected behavior and any tests that already fail.
- Start from the same commit. Give each agent a clean, separate copy. Do not show one agent the other's changes.
- Give both the same information. Include the issue, project rules, relevant files, and test commands.
- Set limits. Record the allowed actions, time or spend limit, model, and permissions. Note any services missing from a remote setup.
- Track your help. Record extra hints and corrections. Review the changes and rerun the checks yourself.
You can test each product's default setup to help decide what to buy. Or keep the model fixed, where supported, to compare the agent tools. Write down which question your trial answers.
Give the agent a clear task
This is a fictional bug example, not a result from testing these tools. A webhook is a request sent from another service when an event happens. Replace the paths and commands before using the prompt.
Issue: A webhook without an event ID returns a server error.
Expected behavior:
- A missing ID gets this project's normal validation response.
- A valid request keeps its current behavior.
- An invalid request causes no writes or queued work.
Repository rules: [file or instructions]
Relevant endpoint: [path]
Focused test command: [command]
Required wider checks: [commands]
Allowed Git actions: [state whether commits, branch pushes,
and pull requests are allowed]
Find the cause. Add a test that fails because of this bug,
then make the smallest suitable fix. Follow project patterns.
Do not weaken tests, add dependencies, or change unrelated code.
Stop and explain if the task needs wider changes.
Report changed files, exact checks and results, and anything
you could not verify. Follow the Git limits above.
Do not deploy or merge.
For cloud tools that need to push a branch or open a pull request, use a dedicated trial repository and allow those actions explicitly. Record this difference from a local run.
Check correctness before speed
For this example, the test should send the invalid request through the code that fails. It should check the validation response and confirm that no data was saved or work queued.
Check that the new test fails with the old code and passes with the fix. Test a valid request too. Read changes to shared helpers and existing tests. Removing a useful check to make a test pass is a failed result.
Use the same scorecard for both tools. A blank means you have not checked that item.
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| Record | Tool A | Tool B |
|---|---|---|
| Product, version, interface, and model | ||
| Starting commit and environment differences | ||
| Correct behavior: pass, fail, or blocked; evidence | ||
| New test fails before the fix and passes after | ||
| Required checks run; checks still missing | ||
| Unrelated changes or new dependencies | ||
| Your setup, guidance, review, and repair minutes | ||
| Total elapsed time, retries, and extra hints | ||
| Usage consumed and extra charges, if visible |
Compare effort and cost only after the result passes review. Repeat with another task, such as changing a function used in several places. Keep mixed results visible instead of choosing a winner from one successful run.
Choose your first two tools
Keep a tool you already have as your starting point, if possible. Add one that addresses a clear need: a different editor, more model choice, better planning, or remote work. Run the same small issue in both and use the scorecard to decide which deserves a longer trial.