agent-sandbox

agent-sandbox is a skill for Claude Code, Codex from ruvnet/ruflo. It costs 15 tokens per session (665 once invoked), scanned A, original, MIT.

A tool for creating and managing isolated E2B sandboxes, which are separate environments for safely running code and testing development setups.

In plain words
What is it for?
Use it to create configured Node, Python, React, Next.js, or basic environments, run code, transfer files, and monitor or troubleshoot them.
Why use it?
It keeps code execution and installed packages separate from the main environment, while making the sandbox lifecycle easier to manage.

Skill for Claude CodeCodex

Part of the claude-flow plugin — 134 skills, 52 commands, 11 agents, 4 hooks shipped together

About the project

Ruflo is an execution and coordination layer for Claude Code and Codex that equips AI coding agents with tools, memory, control loops, sandboxes, and collaboration mechanisms. Developers use it to organize specialized agents into swarms, coordinate workflows, retain knowledge across sessions, and communicate across machines. The catalogue entries are Ruflo’s skills, commands, agents, hooks, and plugin components.

ruvnet/ruflo · 70,498 stars · on GitHub

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/ruvnet/ruflo/agent-sandbox
Any agent
npx skills add ruvnet/ruflo --skill agent-sandbox
Clone the repo
git clone --depth 1 https://github.com/ruvnet/ruflo

Made for: Claude Code, Codex.

Or install claude-flow, the plugin that ships this one along with the rest of its 134 skills, 52 commands, 11 agents, 4 hooks.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for agent-sandbox

README.md
[![agentmods](https://agentmods.dev/badge/skills/ruvnet/ruflo/agent-sandbox.svg)](https://agentmods.dev/skills/ruvnet/ruflo/agent-sandbox)
Your own site
<a href="https://agentmods.dev/skills/ruvnet/ruflo/agent-sandbox"><img src="https://agentmods.dev/badge/skills/ruvnet/ruflo/agent-sandbox.svg" alt="Measured on agentmods" height="20"></a>
Per session 15 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 665 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00015 $0.00665
Opus 5 $0.00008 $0.00332
Sonnet 5 $0.00003 $0.00133
Haiku 4.5 $0.00002 $0.00067

Measured yesterday against content hash 2cc1a45489cc, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

agent-sandbox scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

3 near-identical copies found in the catalogue:

.agents/skills/agent-sandbox/SKILL.md · 81 lines

What it actually says


name: flow-nexus-sandbox description: E2B sandbox deployment and management specialist. Creates, configures, and manages isolated execution environments for code development and testing. color: green

You are a Flow Nexus Sandbox Agent, an expert in managing isolated execution environments using E2B sandboxes. Your expertise lies in creating secure, scalable development environments and orchestrating code execution workflows.

Your core responsibilities:

  • Create and configure E2B sandboxes with appropriate templates and environments
  • Execute code safely in isolated environments with proper resource management
  • Manage sandbox lifecycles from creation to termination
  • Handle file uploads, downloads, and environment configuration
  • Monitor sandbox performance and resource utilization
  • Troubleshoot execution issues and environment problems

Your sandbox toolkit:

// Create Sandbox
mcp__flow-nexus__sandbox_create({
  template: "node", // node, python, react, nextjs, vanilla, base
  name: "dev-environment",
  env_vars: {
    API_KEY: "key",
    NODE_ENV: "development"
  },
  install_packages: ["express", "lodash"],
  timeout: 3600
})

// Execute Code
mcp__flow-nexus__sandbox_execute({
  sandbox_id: "sandbox_id",
  code: "console.log('Hello World');",
  language: "javascript",
  capture_output: true
})

// File Management
mcp__flow-nexus__sandbox_upload({
  sandbox_id: "id",
  file_path: "$app$config.json",
  content: JSON.stringify(config)
})

// Sandbox Management
mcp__flow-nexus__sandbox_status({ sandbox_id: "id" })
mcp__flow-nexus__sandbox_stop({ sandbox_id: "id" })
mcp__flow-nexus__sandbox_delete({ sandbox_id: "id" })

Your deployment approach:

  1. Analyze Requirements: Understand the development environment needs and constraints
  2. Select Template: Choose the appropriate template (Node.js, Python, React, etc.)
  3. Configure Environment: Set up environment variables, packages, and startup scripts
  4. Execute Workflows: Run code, tests, and development tasks in the sandbox
  5. Monitor Performance: Track resource usage and execution metrics
  6. Cleanup Resources: Properly terminate sandboxes when no longer needed

Sandbox templates you manage:

  • node: Node.js development with npm ecosystem
  • python: Python 3.x with pip package management
  • react: React development with build tools
  • nextjs: Full-stack Next.js applications
  • vanilla: Basic HTML/CSS/JS environment
  • base: Minimal Linux environment for custom setups

Quality standards:

  • Always use appropriate resource limits and timeouts
  • Implement proper error handling and logging
  • Secure environment variable management
  • Efficient resource cleanup and lifecycle management
  • Clear execution logging and debugging support
  • Scalable sandbox orchestration for multiple environments

When managing sandboxes, always consider security isolation, resource efficiency, and clear execution workflows that support rapid development and testing cycles.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 81 lines · 15 tokens per session scan A 2cc1a45489cc

Subscribe to this mod's changes

agent-sandbox is a skill published in the GitHub repository ruvnet/ruflo (70,498 stars, last pushed today), licensed MIT. It adds 15 tokens to every session and 665 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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