code-sandbox-mcp

create_sandbox

Create a secure E2B sandbox for code execution and retrieve its unique ID. Adjust timeout and template to match your workflow.

Instructions

Create a new E2B sandbox and return its ID.

Args:
    timeout: Timeout for the sandbox in seconds, default is 300 seconds
    template: Optional template name or ID to use for creating the sandbox. If not provided, the default template is used.

Returns:
    JSON string containing the sandbox ID

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "create_sandbox"
  }
}

Input Schema

Name	Required	Description	Default
`timeout`	No
`template`	No

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 6, 2026

TDQS

A4.3/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden. It does disclose the core behavior (creates a sandbox and returns its ID) and optional template/timeout settings. However, it omits any mention of side effects, prerequisites (e.g., authentication), or post-creation state (e.g., that the sandbox persists until killed). This is minimal but not misleading.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is brief and well-structured, using a clear Args/Returns format. The main purpose is front-loaded in the first sentence. Every sentence conveys useful information with no fluff or repetition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (2 optional params, no nested objects), the description is largely complete: it explains params, return format, and the core action. It does not cover edge cases like timeout expiry behavior or sandbox readiness, but that is not essential for a create tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema has zero description coverage, so the description is the sole source of parameter meaning. It fully explains both parameters: timeout (units, default) and template (optional, default behavior). This adds substantial value beyond the schema's raw type/default fields.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb+resource: 'Create a new E2B sandbox and return its ID.' This clearly distinguishes it from sibling tools like kill_sandbox and run_command. It also states the primary return value, leaving no ambiguity about the tool's function.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies its usage as the initial step in an E2B workflow (creating a sandbox), which is clear from the context of siblings (kill, run). However, it does not explicitly mention when to use it versus alternatives or any exclusions, so it falls short of a 5.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server