Best AI Coding Agent

1:54 The best AI coding agent on Nov 6, 2026 is Claude Code running Claude Opus 5.5, which resolves 64.8% of tasks on Terminal-Bench 4.0, the highest score there, and also leads LMArena WebDev. The best value is OpenAI's Codex: with GPT-6.1 Sol it scores 58.2% on the same benchmark at about an eighth of the run cost, and it is included in every ChatGPT plan. If you want an editor rather than a terminal agent, Cursor and GitHub Copilot are the leading choices, and Copilot's $10 Pro plan is the cheapest paid option.

The field changed hands in 2026: Cursor became part of SpaceX on Aug 14, 2026, Windsurf now continues as Cognition's Devin Desktop, and Google moved free individual use of Gemini CLI to Antigravity CLI on Jun 18, 2026. The verdicts below are dated so you can tell when they go stale.

Quick comparison

Prices are US monthly prices as of Nov 6, 2026.

Benchmarks: who scores highest

Terminal-Bench 4.0 (read Nov 6, 2026) runs each model inside an agent on real terminal tasks and also reports what the run cost. Its top five: Claude Opus 5.5 in Claude Code 64.8%, Claude Sonnet 5.5 in Claude Code 61.8%, GPT-6 Astra and GPT-6.1 Sol in Codex tied at 58.2%, and Claude Fable 5.1 in Claude Code 57.9%. GPT-6.1 Sol's run cost $0.6k against $4.7k for Opus 5.5. The best non-Anthropic, non-OpenAI entries are Zhipu's GLM-5.3 (41.8%, run in Claude Code) and Grok 4.7 in Grok Build (37.6%), the model Cursor calls its most capable. No Gemini 4 model was listed.

LMArena WebDev (as of Oct 27, 2026), where people vote between two generated web apps: Claude Opus 5.5 1810, GPT-6 Astra 1773, Claude Sonnet 5.5 1770, Gemini 4 Carbon 1768 (preliminary) and GPT-6.1 Sol 1751, per LMArena. Moonshot's Kimi K3.1 Pro is the top open-weight entry at ninth.

SWE-bench Verified is no longer a useful guide to today's agents: its official leaderboard, read Nov 6, 2026, has no results newer than Feb 17, 2026, and its top score is 79.2% for systems built on Claude Opus 4.5. Makers now quote other tests, such as DeepSWE and FrontierCode, mostly in their own announcements.

Best overall: Claude Code

0:53 Claude Code has the top two scores on Terminal-Bench 4.0 and runs Anthropic's models, which lead WebDev too. It comes with every paid Claude plan, from Pro at $20; heavy users need Max ($100, 5 times Pro usage) or Ultra ($200, no five-hour limit on verified accounts). The trade-off is cost: Anthropic's runs were among the most expensive on Terminal-Bench, and Pro's limits run out quickly on long agent sessions. In an Aug 10, 2026 video, Tech With Tim called Claude Code his daily driver, on the $200 plan, for quick tasks and smaller coding projects.

Best value: Codex

1:30 Codex is included in ChatGPT Free, Go, Plus, Pro, Business, Edu and Enterprise. On Plus ($20), OpenAI estimates 15 to 160 GPT-6.1 Sol messages every five hours, against 5 to 45 for GPT-6 Astra; Pro plans have no five-hour limit. You can also sign in with an API key and pay API prices instead. Pick Codex if you already pay for ChatGPT or want near-top scores for less. In the same Aug 10, 2026 video, Tech With Tim said he reaches for Codex for more complex development work because it tests and verifies its code more completely.

Best AI code editor: Cursor

2:22 Cursor is an editor built around agents: chat, Tab completion, cloud agents and code review in one app. Since joining SpaceX, its plans share one usage pool across Cursor and Grok, and only Grok models are included; third-party models such as Claude and GPT are billed at their API list price. That makes Cursor cheap with Grok ($8 Plus) but no cheaper than the makers' own tools if you want Claude or GPT. Recent additions include an Agent SDK (Oct 20, 2026) and Projects (Sep 10, 2026), per Cursor's blog. In a Feb 10, 2026 video, before the SpaceX deal, Tech With Tim showed Cursor's agent working in its VS Code-based editor and said he prefers it for smaller edits he reviews line by line.

Best inside GitHub and the cheapest paid plan: GitHub Copilot

13:29 GitHub Copilot works in VS Code, JetBrains and other editors and on GitHub itself, where you can assign an issue to its coding agent and get a pull request back. Plans are priced in AI credits worth $0.01 each: Pro ($10) includes $15 of credits a month, Pro+ ($39) $70, and Max ($100) $200. Pro+ and Max can also run third-party agents such as Claude and Codex inside GitHub. Free includes 2,000 completions a month. In a Feb 10, 2026 video, Tech With Tim said he uses Copilot mostly on GitHub, for automated pull requests, GitHub Actions and code review, rather than in his editor.

Other agents worth knowing

Devin is Cognition's autonomous engineer; Windsurf, which Cognition took over in 2025, continues as Devin Desktop since Jun 2, 2026, and windsurf.com's pricing page now opens Devin's. Cognition released its own SWE-2 model on Sep 10, 2026 and SWE-2 Flash on Nov 4, 2026.

Google Antigravity is Google's agent-first IDE and, since Jun 18, 2026, the home of Antigravity CLI, which replaced Gemini CLI for individuals. Google AI Pro and Ultra raise its limits and give access to Gemini 4 Argon.

Kiro from AWS starts from written specifications before code. Its plans are credit-based, from 50 free credits to 10,000 on the $200 Power plan.

Jules is Google's asynchronous agent: label a GitHub issue and it clones the repository to a cloud VM, plans, and opens a pull request. Its page, read Nov 6, 2026, still names older Gemini models.

Cline is the open-source pick: free for individuals, working with any model through your own API key, so you pay only your provider.

JetBrains AI, Replit, Lovable, v0 and Bolt suit JetBrains users and people building whole apps from a prompt rather than working in an existing codebase.

How we chose

Scores come from Terminal-Bench 4.0 and LMArena WebDev, read on Nov 6, 2026 with the dates they show, and we checked the SWE-bench Verified leaderboard the same day. Benchmarks measure a model inside one agent; the same model can score differently in another tool. Prices and plan contents come from each maker's own pricing page, read Nov 6, 2026. We did not run our own tests. See AI Leaderboards for what each benchmark measures.

Frequently asked questions

What is the best AI coding agent in 2026? Claude Code with Claude Opus 5.5 is the best AI coding agent by benchmark as of Nov 6, 2026, first on Terminal-Bench 4.0 at 64.8% and on LMArena WebDev. Codex with GPT-6.1 Sol is the best value at 58.2% for far less.

Is Claude Code better than Codex? Claude Code scores higher than Codex on Terminal-Bench 4.0 (64.8% against 58.2%, read Nov 6, 2026), but Codex reached its score at about an eighth of the cost and comes with every ChatGPT plan, including Free.

Is Cursor still worth it? Cursor is worth it if you want an AI-first editor and are happy with Grok models, which its plans include from $8 a month; Claude and GPT models in Cursor cost extra at API prices since it became part of SpaceX.

What is the cheapest AI coding agent? Cline is free and open source if you bring your own API key, Codex comes with ChatGPT's free plan, and GitHub Copilot Pro is the cheapest paid plan at $10 a month, as of Nov 6, 2026.

What happened to Windsurf? Windsurf belongs to Cognition, the maker of Devin, and continues as Devin Desktop, which Cognition calls the next generation of Windsurf; windsurf.com's pricing now leads to Devin's plans.

Is Gemini CLI still free? No, not for individuals: since Jun 18, 2026 Google sends individuals to Antigravity CLI, and Gemini CLI serves Gemini Code Assist customers and paid API keys.

Sources

• Terminal-Bench 4.0 leaderboard, Terminal-Bench, read Nov 6, 2026
• WebDev leaderboard, LMArena, read Nov 6, 2026
• SWE-bench Verified, SWE-bench, read Nov 6, 2026
• Plans and pricing, Claude, read Nov 6, 2026
• Codex pricing, OpenAI, read Nov 6, 2026
• Pricing and Blog, Cursor, read Nov 6, 2026
• GitHub Copilot plans, GitHub, read Nov 6, 2026
• Pricing, Devin, read Nov 6, 2026
• Blog, Cognition, read Nov 6, 2026
• google-gemini/gemini-cli, GitHub, read Nov 6, 2026
• Gemini 4 Argon is now available in the Gemini app, Google, Oct 13, 2026
• Google Meet's Gemini-powered 'Take notes for me' comes to Google AI Pro, Ultra, 9to5Google, Jun 29, 2026
• Pricing, Kiro, read Nov 6, 2026
• Jules, Google, read Nov 6, 2026
• Pricing, Cline, read Nov 6, 2026
• The Only AI Coding Tools Worth Learning in 2026, Tech With Tim, Feb 10, 2026 (video)
• The Best AI Tools for Developers in 2026 (That I Actually Use), Tech With Tim, Aug 10, 2026 (video)