An agent skill for managing isolated execution environments using E2B Sandboxes. This skill enables AI agents (Gemini CLI, Claude Code, Codex CLI) to safely execute code, build full-stack applications, and perform arbitrary engineering tasks in a secure, isolated sandbox.
Watch the Gemini 3 Demo or the newer Claude Opus 4.5 Demo to understand what this codebase/skill can do for your agentic coding.
Agent Sandboxes unlock 3 key capabilities for your agentic engineering:
- Isolation: Each agent fork runs in a fully isolated, gated E2B sandbox, this means no matter what your agent does, it's secure and safe from your local filesystem and production environment.
- Scale: You can run as many agent forks as you want, each fork is independent and has its own sandbox. This is a very literal way to scale your compute to scale your impact.
- Agency: Your agents have full control over the sandbox environment, they can install packages, modify files, run commands, etc. This means they can handle more of the engineering process for you.
- Isolated Execution: Run untrusted code, tests, and binaries safely.
- Full-Stack Development: Scaffold, build, and host Vue + FastAPI + SQLite apps.
- Browser Automation: Built-in Playwright integration for visual validation.
- Agent-First Design: Optimized for CLI agents with structured prompts and robust error handling.
- Persistent Context: Tools to manage sandbox lifecycles across agent turns.
- Python >= 3.12
uvpackage manager (recommended)- E2B Account & API Key
-
Clone the repository (if not already done).
-
Configure Environment: Create a
.envfile in the project root:cp .env.sample .env
Add your E2B API key:
E2B_API_KEY=sbx_...
(Get your key from E2B Dashboard)
-
Open your Agentic Coding Tool: Open your Agentic Coding Tool and start prompting!
claude or gemini or codex
Then for one of simple tasks run:
\sandbox <prompt>
For complex tasks run
\plan-build-host-test <prompt> <workflow_id>
The prompts/{claude,gemini,codex}/<difficulty>_<task>.md contain full stack application prompts you can
Try these prompts out with a SOTA Model for the best results.
Run these prompts in your Agentic Coding Tool.
Start with the Very Easy Prompts to get a feel for the tool. Keep in mind token usage increases as the complexity of the prompt increases.
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/very_easy_guestbook.md)" "very_easy_guestbook"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/very_easy_url_shortener.md)" "very_easy_url_shortener"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/very_easy_counter.md)" "very_easy_counter"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/very_easy_poll_maker.md)" "very_easy_poll_maker"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/very_easy_calculator.md)" "very_easy_calculator"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/very_easy_counter.md)" "very_easy_counter"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/very_easy_greeter.md)" "very_easy_greeter"\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/easy_api_mock_studio.md)" "easy_api_mock_studio"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/easy_code_snippet_manager.md)" "easy_code_snippet_manager"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/easy_cron_heartbeat_monitor.md)" "easy_cron_heartbeat_monitor"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/easy_markdown_knowledge_base.md)" "easy_markdown_knowledge_base"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/easy_offline_task_board.md)" "easy_offline_task_board"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/easy_schema_visualizer.md)" "easy_schema_visualizer"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/easy_nano_banana_simple.md)" "easy_nano_banana_simple"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/easy_notes_app.md)" "easy_notes_app"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/easy_sqlite_crud.md)" "easy_sqlite_crud"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/easy_todo_list.md)" "easy_todo_list"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/easy_chart_sketch.md)" "easy_chart_sketch"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/easy_decision_matrix.md)" "easy_decision_matrix"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/easy_design_system_palette.md)" "easy_design_system_palette"\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/medium_knowledge_base_curator.md)" "medium_knowledge_base_curator"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/medium_devops_dashboard.md)" "medium_devops_dashboard"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/medium_investment_tracker.md)" "medium_investment_tracker"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/medium_log_analysis_tool.md)" "medium_log_analysis_tool"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/gemini/medium_planning_poker.md)" "medium_planning_poker"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/opus45/medium_elevenlabs_live_transcription_app.md)" "medium_elevenlabs_live_transcription_app"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/medium_file_explorer.md)" "medium_file_explorer"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/medium_habit_tracker.md)" "medium_habit_tracker"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/medium_nano_banana_generator.md)" "medium_nano_banana_generator"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/medium_personal_finance.md)" "medium_personal_finance"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/medium_recipe_planner.md)" "medium_recipe_planner"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/medium_chart_sketch_pro.md)" "medium_chart_sketch_pro"\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/hard_incident_response_notebook.md)" "hard_incident_response_notebook"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/hard_learning_cohort_orchestrator.md)" "hard_learning_cohort_orchestrator"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/hard_supplier_quality_portal.md)" "hard_supplier_quality_portal"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/hard_ui_design_review_platform.md)" "hard_ui_design_review_platform"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/hard_api_testing.md)" "hard_api_testing"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/hard_code_snippets.md)" "hard_code_snippets"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/hard_content_workflow.md)" "hard_content_workflow"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/hard_freelancer_manager.md)" "hard_freelancer_manager"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/hard_nano_banana_studio.md)" "hard_nano_banana_studio"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/hard_time_tracking.md)" "hard_time_tracking"\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/very_hard_analytics_ops_monitoring_hub.md)" "very_hard_analytics_ops_monitoring_hub"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/very_hard_iot_fleet_maintenance_console.md)" "very_hard_iot_fleet_maintenance_console"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/very_hard_micro_betting_odds_lab.md)" "very_hard_micro_betting_odds_lab"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/very_hard_personal_investing_allocator.md)" "very_hard_personal_investing_allocator"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/codex/very_hard_scriptwriter_automation_workbench.md)" "very_hard_scriptwriter_automation_workbench"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/very_hard_knowledge_base.md)" "very_hard_knowledge_base"
\agent-sandboxes:plan-build-host-test "$(cat prompts/full_stack/sonnet/very_hard_system_monitor.md)" "very_hard_system_monitor"after you host your app via public url, you can test it with the browser testing prompts.
# Claude Code only - requires subagent support (parallel=true, headed=true)
/generic-browser-test https://www.anthropic.com/news/claude-opus-4-5 prompts/browser-workflows/opus-4-5-release.md true true
# Sandbox app browser tests (replace <URL> with actual sandbox URL)
/generic-browser-test <URL> prompts/browser-workflows/easy_chart_sketch_browser_test.md true true
/generic-browser-test <URL> prompts/browser-workflows/easy_decision_matrix_browser_test.md true true
/generic-browser-test <URL> prompts/browser-workflows/easy_design_system_palette_browser_test.md true true
/generic-browser-test <URL> prompts/browser-workflows/medium_chart_sketch_pro_browser_test.md true true
# For other agentic coding tools, make sure subagents is false
\generic-browser-test <URL> prompts/browser-workflows/easy_chart_sketch_browser_test.md false trueThis project uses "reprogrammed" backslash commands to trigger agent workflows. See CLAUDE.md, AGENTS.md, and GEMINI.md for more details.
| Command | Description |
|---|---|
\sandbox <prompt> |
Small general sandbox operations. An adhoc prompt with minimal compute usage. |
\agent-sandboxes:plan-full-stack <prompt> |
Generates a detailed implementation plan with Browser UI Testing workflows. |
\agent-sandboxes:build <plan_path> |
Executes a build plan within a sandbox. |
\agent-sandboxes:host <sandbox_id> <port> |
Exposes a port and returns a public URL. |
\agent-sandboxes:test <sandbox_id> <url> <plan_path> <workflow_id> |
Runs validation tests against the hosted app including browser UI testing. |
\agent-sandboxes:browser-testing <sandbox_id> <url> <plan_path> <workflow_id> |
Executes browser UI testing workflows from a plan using parallel subagents (headed default). |
\agent-sandboxes:plan-build-host-test <prompt> <workflow_id> |
Agentic-Workflow: Orchestrates a full lifecycle: Plan → Build → Host → Test. |
You can also run the CLI manually for debugging or inspection:
# From .claude/skills/agent-sandboxes/sandbox_cli/
uv run sbx --help- Init:
uv run sbx init --timeout 1800 - Execute:
uv run sbx exec <sandbox_id> "echo hello" - Files:
uv run sbx files ls <sandbox_id> /home/user - Browser:
uv run sbx browser start
- CLI: Python-based (
click,e2b,rich) located in.claude/skills/agent-sandboxes/sandbox_cli/. - Prompts: Markdown-based prompt templates in
.claude/skills/agent-sandboxes/prompts/. - Skill Definition:
SKILL.mddefines the capabilities exposed to the agent.
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