FetchSandbox is a specialized API integration testing platform designed for the era of AI-assisted development. As more developers use AI coding assistants like Cursor, Claude Code, and Codex CLI to write integrations, the risk of shipping broken API code has increased dramatically. FetchSandbox addresses this by providing a memory graph that lets AI agents test API integrations deterministically — verifying webhook delivery, workflow state transitions, async behavior, and failure scenarios — all without burning real API quota or touching production environments.
Core Features
- Pre-Configured API Sandboxes: Ready-to-use testing environments for Stripe, GitHub, OpenAI, Twilio, Resend, Clerk, WorkOS, and 60+ other APIs — no complex setup required
- MCP Integration: Connects directly to Cursor, Claude Code, Windsurf, VS Code, and Codex via the Model Context Protocol, enabling AI agents to test integrations within the IDE
- Deterministic Testing: The same prompt produces the same outcome every time, with reproducible bug scenarios and verifiable fixes
- Complete Workflow Simulation: Tests webhook delivery, retries, state changes, async workflows, and failure scenarios end-to-end — not just API response codes
- Receipt URLs: Every test run generates a public, replayable receipt URL that can be shared in PRs and Slack for team review
- Zero Quota Burn: All testing happens in sandboxed environments, ensuring zero impact on real API quotas or production data
Use Cases
FetchSandbox is built for developers and engineering teams who use AI coding assistants in their daily workflow. Backend engineers can validate Stripe payment integrations, including edge cases like duplicate webhooks and failed retries, before deploying to production. Full-stack developers can test Twilio SMS workflows and email delivery pipelines without sending real messages. Platform teams can use FetchSandbox in CI/CD pipelines via CLI and GitHub Actions to ensure integrations remain reliable. AI agent developers building MCP-compatible tools can leverage the platform to verify their integrations handle real-world failure modes correctly.
Pricing
FetchSandbox offers a free tier for individual developers to get started with basic API testing. Paid plans with expanded request limits and team features are available for professional and enterprise use. Visit the official website for the most current pricing details.
How to Access
Official website: FetchSandbox











