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+---
+name: reproduce-bug
+description: Reproduce a bug from a Linear ticket with a failing test. Expects the full ticket context (title, description, comments) to be provided as input.
+user_invocable: true
+---
+
+# Bug Reproduction Framework
+
+Given a Linear ticket context ($ARGUMENTS), systematically reproduce the bug
+with a failing regression test.
+
+## Step 1: Parse Signals
+
+Extract the following from the provided ticket context:
+- **Error message / stack trace** (if provided)
+- **Reproduction steps** (if provided)
+- **Workflow JSON** (if attached)
+- **Affected area** (node, execution engine, editor, API, config, etc.)
+- **Version where it broke / last working version**
+
+
+## Step 2: Route to Test Strategy
+
+Based on the affected area, pick the test layer and pattern:
+
+| Area | Test Layer | Pattern | Key Location |
+|------|-----------|---------|--------------|
+| Node operation | Jest unit | NodeTestHarness + nock | `packages/nodes-base/nodes/*/test/` |
+| Node credential | Jest unit | jest-mock-extended | `packages/nodes-base/nodes/*/test/` |
+| Trigger webhook | Jest unit | mock IHookFunctions + jest.mock GenericFunctions | `packages/nodes-base/nodes/*/test/` |
+| Binary data | Jest unit | NodeTestHarness assertBinaryData | `packages/core/nodes-testing/` |
+| Execution engine | Jest integration | WorkflowRunner + DI container | `packages/cli/src/__tests__/` |
+| CLI / API | Jest integration | setupTestServer + supertest | `packages/cli/test/integration/` |
+| Config | Jest unit | GlobalConfig + Container | `packages/@n8n/config/src/__tests__/` |
+| Editor UI | Vitest | Vue Test Utils + Pinia | `packages/frontend/editor-ui/src/**/__tests__/` |
+| E2E / Canvas | Playwright | Test containers + composables | `packages/testing/playwright/` |
+
+## Step 3: Locate Source Files
+
+Find the source code for the affected area:
+1. Search for the node/service/component mentioned in the ticket
+2. Find the GenericFunctions file (common bug location for nodes)
+3. Check for existing test files in the same area
+4. Look at recent git history on affected files (`git log --oneline -10 -- <path>`)
+
+## Step 4: Trace the Code Path
+
+Read the source code and trace the execution path that triggers the bug:
+- Follow the call chain from entry point to the failure
+- Identify the specific line(s) where the bug manifests
+- Note any error handling (or lack thereof) around the bug
+
+## Step 5: Form Hypothesis
+
+State a clear, testable hypothesis:
+- "When [input/condition], the code does [wrong thing] because [root cause]"
+- Identify the exact line(s) that need to change
+- Predict what the test output will show
+
+## Step 6: Find Test Patterns
+
+Look for existing tests in the same area:
+1. Check `test/` directories near the affected code
+2. Identify which mock/setup patterns they use
+3. Use the same patterns for consistency
+4. If no tests exist, find the closest similar node/service tests as a template
+
+## Step 7: Write Failing Test
+
+Write a regression test that:
+- Uses the patterns found in Step 6
+- Targets the specific hypothesis from Step 5
+- Includes a comment referencing the ticket ID
+- Asserts the CORRECT behavior (test will fail on current code)
+- Also includes a "happy path" test to prove the setup works
+
+## Step 8: Run and Score
+
+Run the test from the package directory (e.g., `cd packages/nodes-base && pnpm test <file>`).
+
+Classify the result:
+
+| Confidence | Criteria | Output |
+|------------|----------|--------|
+| **CONFIRMED** | Test fails consistently, failure matches hypothesis | Reproduction Report |
+| **LIKELY** | Test fails but failure mode differs slightly | Report + caveat |
+| **UNCONFIRMED** | Cannot trigger the failure | Report: what was tried |
+| **SKIPPED** | Hit a hard bailout trigger | Report: why skipped |
+| **ALREADY_FIXED** | Bug no longer reproduces on current code | Report: when fixed |
+
+## Step 9: Iterate or Bail
+
+If UNCONFIRMED after first attempt:
+- Revisit hypothesis — re-read the code path
+- Try a different test approach or layer
+- Maximum 3 attempts before declaring UNCONFIRMED
+
+**Hard bailout triggers** (stop immediately):
+- Requires real third-party API credentials
+- Race condition / timing-dependent
+- Requires specific cloud/enterprise infrastructure
+- Requires manual UI interaction that can't be scripted
+
+## Output: Reproduction Report
+
+Present findings in this format:
+
+---
+
+**Ticket:** [ID] — [title]
+**Confidence:** [CONFIRMED | LIKELY | UNCONFIRMED | SKIPPED | ALREADY_FIXED]
+
+### Root Cause
+[1-2 sentences explaining the bug mechanism]
+
+### Location
+| File | Lines | Issue |
+|------|-------|-------|
+| `path/to/file.ts` | XX-YY | Description of the problem |
+
+### Failing Test
+`path/to/test/file.test.ts` — X/Y tests fail:
+1. `test name` — [failure description]
+
+### Fix Hint
+[Pseudocode or description of the fix approach]
+
+---
+
+## Important
+
+- **DO NOT fix the bug** — only reproduce it with a failing test
+- **Leave test files in place** as evidence (don't commit unless asked)
+- **Run tests from the package directory** (e.g., `pushd packages/nodes-base && pnpm test <file> && popd`)
+- **Always redirect build output**: `pnpm build > build.log 2>&1`
+- **DO NOT look at existing fix PRs** — the goal is to reproduce from signals alone