FetchSandbox MCP
The MCP that proves your AI's integration fixes work
In plain words
FetchSandbox MCP is a testing tool that helps developers verify AI agent code actually works with real APIs. It runs over 70 API sandboxes to simulate real-world failures and confirms that integration fixes remain stable across multiple test runs. The tool integrates directly into coding assistants like Cursor and Claude Code without requiring API keys or vendor accounts, letting developers test workflows end-to-end and catch production failures before they happen. It's designed for teams building API integrations through AI-assisted coding.
written from the facts on this page · September 2026
From the sources
Your agent's integration fix passes CI. The data is still wrong. FetchSandbox MCP reproduces the real failure on your code, fixes it, and proves the fix held. A receipt, not a vibe. 70+ API sandboxes. One config block in Cursor or Claude Code.
Your agent's code passes. The workflow still breaks. FetchSandbox runs every service the workflow touches, makes them misbehave the way the real ones do, and checks the end state was right — then re-runs the identical scenario to prove the fix held. One MCP config into Cursor, Claude Code or Codex. No keys, no vendor accounts.
Run every service the workflow touches, make them fail the way the real ones do, and prove the fix held — without burning real API quota. Build and test API integrations without leaving your AI coding assistant. Your agent stops shipping integrations that “work” in tests but break in production. Every workflow run includes the spec of what success looks like — terminal state, required webhook events, invariants — verified end-to-end. Connect your tools, test real API workflows, and ship integrations with confidence. Add FetchSandbox to your IDE and start testing APIs in minutes. Works with Cursor, VS Code, Claude Code, Windsurf, and more. Simulate real API behavior like webhooks, retries,…from fetchsandbox.com
Pricing, as stated on its site
Free tier, paid plans from $5/mo — Free tier with 1,000 runs/month. Pro plan at $5/month with 10,000 runs/month plus pay-as-you-go overage ($5 per extra 10,000 runs). Enterprise with custom pricing.
checked September 2026 · prices change
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