# Do coding agents recommend CodeSandbox SDK? > Coding agents raised CodeSandbox SDK in 70 of 299 judged code sandboxes sessions and chose it in none of them. Measured with Claude Code, Codex and Cursor. Source: https://armature.tech/library/do-coding-agents-recommend-codesandbox-sdk Published: 2026-09-03 Publisher: Armature, Inc. (https://armature.tech) --- > Coding agents raised CodeSandbox SDK in 70 of 299 judged code sandboxes sessions and chose it in none of them. This page reports what happened when Claude Code, Codex and Cursor had to solve a problem in code sandboxes inside a realistic codebase. Not what a chat assistant says about CodeSandbox SDK. What an agent actually installed. ## The numbers | | | | --- | --- | | Category | Code sandboxes | | Sessions in the category | 299 | | Sessions where CodeSandbox SDK was chosen | 0 | | Install share | 0% | | Raised as a candidate, not chosen | 70 | | Chosen when considered | 0% | | Site | codesandbox.io | ## Which agents raised CodeSandbox SDK Every agent considered it and none adopted it. Cursor raised it most often, in 40% of its code sandboxes sessions. | Agent | Sessions | Raised CodeSandbox SDK | Chose it | | --- | --- | --- | --- | | Claude Code | 95 | 26 (27%) | 0 | | Codex | 102 | 3 (3%) | 0 | | Cursor | 102 | 41 (40%) | 0 | ## Which buyers it came up for It surfaced most for requests written as senior engineer, in 23% of those sessions. Knowing which buyer already has the product in mind tells you which pages to fix first. | Who is asking | Sessions | Raised it | | --- | --- | --- | | Senior engineer | 269 | 63 (23%) | | Enterprise team | 30 | 7 (23%) | ## What CodeSandbox SDK was up against The full ranking in code sandboxes, from the same sessions: | # | Product | Runs won | Share | | --- | --- | --- | --- | | 1 | E2B | 127 | 42% | | 2 | Modal | 74 | 25% | | 3 | Daytona | 47 | 16% | | 4 | Vercel Sandbox | 43 | 14% | | 5 | Anthropic Code Execution | 3 | 1% | | 6 | Runloop Devboxes | 3 | 1% | | 7 | Cloudflare Workers | 2 | 1% | ## What this means Raised 70 times and chosen none is a specific, diagnosable result, and a better starting position than being unknown. The agent has the product in mind. It reached the shortlist 70 times. Something then lost every one of those sessions. In our data the causes, in the order they occur: - The quickstart does not run when pasted, so the agent abandoned it mid-integration. - The documentation describes an interface that changed, so the generated code failed. - The product name and the package name differ, so the install step went wrong. - The fit was genuinely wrong for the repository, which is fine and worth knowing. All but the last are fixable in days, and the reason is written down in the session transcript. ## Where these numbers come from The 299 sessions in code sandboxes are part of a published set of 5,292, run with real coding agents inside realistic codebases and judged blind. The full method is on one page: [how we measured this](/library/how-we-measured-this). Every code sandboxes run can be replayed on [the board](/leaderboards/sandboxes). If you work on CodeSandbox SDK: the judge recorded a reason for every session where it was raised and passed over. Those reasons are in the transcripts. ## Common questions ### Do coding agents recommend CodeSandbox SDK? They raise it but do not choose it. Across 70 sessions where CodeSandbox SDK came up as a candidate, agents chose something else every time. ### Does Claude Code recommend CodeSandbox SDK? In 0 of the 95 sessions in code sandboxes run with Claude Code, which is 0%. ### Do different coding agents treat CodeSandbox SDK differently? Not much. The three agents chose it at similar rates, between 0% and 0% of their runs. ### How was this measured? Real coding agents at pinned versions were run in sandboxes inside 51 realistic codebases and asked to solve real tasks. A simulated project owner approved or questioned each recommendation before any code was written, and a judge from a model family that builds none of the agents read every session blind. ## Read next - [How to get picked for code sandboxes by coding agents](https://armature.tech/library/sandboxes-coding-agents-playbook) (Markdown: https://armature.tech/library/sandboxes-coding-agents-playbook.md) - [Do coding agents recommend E2B?](https://armature.tech/library/do-coding-agents-recommend-e2b) (Markdown: https://armature.tech/library/do-coding-agents-recommend-e2b.md) - [Do coding agents recommend Modal?](https://armature.tech/library/do-coding-agents-recommend-modal) (Markdown: https://armature.tech/library/do-coding-agents-recommend-modal.md) - [Do Claude Code, Codex and Cursor pick the same tools?](https://armature.tech/library/do-claude-code-and-codex-agree) (Markdown: https://armature.tech/library/do-claude-code-and-codex-agree.md) --- Armature helps software products get discovered and used by coding agents. Service: https://armature.tech/discoverability · Results: https://armature.tech/leaderboards/sectors · Contact: contact@armature.tech