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Partly proven

The failure class is proven below — a deliberately buggy handler and a fixed one were run against the same inputs, and they diverged. A fix on your own code has not been proven on this receipt. That is a separate claim, and only prove_fix establishes it — it reproduces the bug on your repository, applies your diff, and re-runs. Call it before you apply the fix, because it needs the still-broken tree.

sandbox · 54883e52c632
2 other runs →
Scoped to run run_df1d3a1b-9b77-4fa7-a954-40915ded6c28.View all 3 runs →
ⓘRestored from a saved snapshot — payloads and results are exactly as captured.
54883E52C632 · reference testBug reproduced

The buggy handler accepted a request the fix rejects

Same input fired at the vulnerable and correct reference handlers.

Before the fix
request accepted
before the fix
After the fix
request rejected
after the fix
2 related checks passed0 unexpected failures2 webhook deliveries tested1 expected error responsetook 2483ms
ⓘFetchSandbox reference handlers. Behavioral simulation. Buggy and fixed handlers are FetchSandbox-controlled reference implementations — NOT your code. The diff proves the bug pattern is real and the fix_pattern works; apply the brain's fix_pattern to your routes to inherit the same behavior.

what changed

The same request, before your fix vs. after — this is what the bug did, and what it does once fixed.

Before the fix
request accepted
  1. First deliveryside effect created
  2. Duplicate deliveryside effect created
After the fix
request rejected
  1. First deliveryside effect created
  2. Duplicate deliveryside effect created

request timeline

Before the fix · reference handler
After the fix · reference handler

run timeline

Every request and webhook the run made, in order.

  1. 11:01:44.473POST /emails20021ms
  2. 11:01:44.483GET /emails/7fb925a4-a35d-4b4d-a338-fdd492016f232001ms
ok failed webhook

full request history (2)

timetypepath / eventstatusdur

run metadata

sandbox id: 2ee6b5b2easpec: 54883e52c632status: runningscenario: defaultrun id: run_df1d3a1b-9b77-4fa7-a954-40915ded6c28requests: 2
Generated by FetchSandbox — anyone with this link can read the proof.