424 - Failed Dependency
HTTP 424 Failed Dependency means the request could not complete because a dependent action failed first.
Last reviewed: February 12, 2026|Editorial standard: source-backed technical guidance
What Does Failed Dependency Mean?
This operation depends on another step that failed, so the dependent action is aborted to prevent inconsistent workflow state.
Common Causes
- -A prerequisite action in the workflow failed.
- -Batch operation contains dependent steps and earlier step failed.
- -Orchestrator continues dependent actions after blocking failure.
How to Fix Failed Dependency
- 1Identify the prerequisite action that failed before the dependent request.
- 2Fix the upstream dependency failure and rerun the workflow in order.
- 3Add fail-fast guards so dependent steps stop after prerequisite failures.
Step-by-Step Diagnosis for Failed Dependency
- 1Capture workflow execution logs and locate the exact prerequisite step that failed first.
- 2Correlate request IDs across orchestrator, queue, and downstream services in the same transaction chain.
- 3Validate dependency contracts, step ordering, and compensation behavior for partial failures.
- 4Retest by replaying the dependency chain from the failed prerequisite onward.
Dependency Graph and Step-Order Validation
- -Trace directed dependency order (example: publish step executed before required validation step completed).
- -Inspect per-step output contracts (example: downstream step expects artifact ID, upstream failure returned null placeholder).
Orchestration Failure Propagation and Compensation
- -Audit fail-fast behavior (example: orchestrator continued dependent tasks after prerequisite timeout).
- -Verify compensation/rollback handlers (example: step rollback failed, leaving chain in partial state and triggering repeated 424).
Implementation Examples
curl -i -X POST https://api.example.com/v1/resource -H "Content-Type: application/json" -d "{"sample":true}"
# Response:
# HTTP/1.1 424 Failed Dependency
# {"error":"Failed Dependency","code":"424"}const response = await fetch('https://api.example.com/v1/resource', {
method: 'POST',
headers: { 'Content-Type': 'application/json', 'Accept': 'application/json' },
body: JSON.stringify({ sample: true })
});
if (response.status === 424) {
console.error('Handle 424 Failed Dependency');
}import requests
response = requests.post(
'https://api.example.com/v1/resource',
headers={'Accept': 'application/json', 'Content-Type': 'application/json'},
json={'sample': True}
)
if response.status_code == 424:
print('Handle 424 Failed Dependency')How to Verify the Fix
- -Re-run the workflow and confirm dependent steps no longer return 424.
- -Validate traces show prerequisite completion before dependent execution.
- -Track dependency-chain error metrics to confirm sustained recovery.
How to Prevent Recurrence
- -Model dependencies explicitly and enforce deterministic execution order.
- -Implement compensation handlers for prerequisite failures.
- -Add integration tests that assert dependent-step suppression on failures.
Pro Tip
- -emit a machine-readable `failed_prerequisite_step` field so clients and operators can immediately jump to root cause instead of debugging the blocked step.
Decision Support
Compare Guide
409 Conflict vs 412 Precondition Failed: When to Use Each
Choose 412 when If-Match or If-Unmodified-Since checks fail; choose 409 for state conflicts without failed precondition headers during concurrent updates.
Playbook
Conflict and Concurrency Playbook (409 / 412 / OptimisticLock)
Use this playbook to separate true write conflicts from stale precondition failures, then apply safe re-fetch, optimistic-lock, and retry choices.
Official References
Provider Context
This guidance is specific to HTTP services. Always validate implementation details against official provider documentation before deploying to production.