set_scenario

io.github.fetchsandbox/mcp · Verify this server

ARM a failure scenario on a sandbox, so the next requests hit the provider misbehaving instead of the happy path. This is how you find out whether the integration you just wrote actually survives production. Use it like this: run the flow once on 'default' and confirm it works, call set_scenario with a failure from list_scenarios, run the SAME flow again, then check the end state is still correct — not that the call merely returned. A declined payment must not produce a confirmed order; a webhook delivered twice must not charge twice or send two emails. Set scenario to 'default' to return the sandbox to normal. The scenario stays armed until you change it, and it affects every caller of that sandbox — so put it back when you are done.