Truncated Error Messages in Webhook Gateways: A Signal Worth Checking Before You Commit

Debugging a webhook failure without the full error response is like reading a stack trace with the most relevant frames stripped out. See the webhook debugging checklist for a systematic approach that accounts for this. Read Hookdeck G2 reviews for user experiences with error message completeness.

You can infer some things from what remains. You know something went wrong. You know roughly where in the flow it happened. But the information that would let you reproduce the problem, understand its root cause, and write a definitive fix — that's in the response body your handler returned, or in the error message your downstream service generated, or in the validation failure your processing logic emitted. If that content is truncated at the display layer, you're debugging with partial evidence.

This is why error message completeness matters as an evaluation criterion for webhook infrastructure tooling, not just as a nice-to-have, but as a core capability that either supports or impedes your team's ability to debug production incidents quickly.

What Good Error Context Looks Like

Good error context means the complete record: every character your handler returned, every header, every timestamp — truncation anywhere in that chain degrades diagnostic fidelity.

HTTP status code is the baseline. A 500 is different from a 422, which is different from a 403. The status code tells you the failure category: server error, validation rejection, authorization failure. It tells you which part of the stack is responding and what kind of response to expect.

Full response body is where the diagnosis actually happens. A well-instrumented handler returns a response body on failure that includes the specific error: which field failed validation, which database constraint was violated, which external service returned an unexpected result. A handler returning {"error": "payment_method_invalid", "field": "card_cvc", "code": "incorrect_cvc"} gives you everything you need to understand what happened and reproduce it. A truncated display of that response — {"error": "payment_method_inva... — strips the diagnostic value at the exact point where it becomes actionable.

Response headers round out the picture. Headers carry latency signals (X-Response-Time), rate limiting information (X-RateLimit-Remaining), request correlation IDs (X-Request-ID), and in some architectures, validation error detail that doesn't appear in the body. If a gateway captures headers and you can access them, the debugging surface is meaningfully wider.

Timestamps and latency add the temporal dimension. Knowing that a delivery attempt took 28,000ms before timing out is different from knowing it returned 500 in 200ms — the first points to a timeout or deadlock, the second to a fast-failing handler error. Latency at each retry attempt traces the behavior of a recovering system over time.

Good error context is the complete record. Every character your handler returned. Every header. Every timestamp. Truncation anywhere in that chain degrades diagnostic fidelity.

The Reviewer Signal on Hookdeck

This context matters for evaluating a signal that appeared in G2 reviews of Hookdeck.

A G2 reviewer, posted May 8, 2025, noted that "error messages are truncated for the event delivery." This is a single data point from a specific point in time — Hookdeck may have updated display behavior since then, and this reviewer's experience may not match everyone's. Treat it as a signal worth investigating rather than a definitive verdict.

What makes the signal worth investigating is the specificity. "Truncated for the event delivery" is not a vague complaint about UI aesthetics — it describes a concrete behavior in a specific context. The event delivery log, which is where you go to understand why an event failed, was showing truncated error messages. That's the high-stakes debugging context where truncation matters most.

Hookdeck's observability layer is, in general, one of the platform's genuine strengths. The delivery log provides retry history, attempt timing, and outcome visibility that many competing tools don't match. The G2 reviewer wasn't describing a platform with poor observability — they were describing a specific gap in how error message content was displayed. Those two things can both be true simultaneously.

The takeaway is not "Hookdeck has bad debugging tools." The takeaway is "there is a public report of error message truncation in the delivery log, and if complete error context is important to your debugging workflow, it's worth testing this behavior explicitly before you commit to the integration."

Why Truncation Happens in Gateways

Truncated error display in webhook gateways usually comes down to one of a few design tradeoffs, and understanding them helps you ask the right questions during evaluation.

UI display limits vs. stored payload size are often different constraints. A gateway might store the full response body but cap the UI display at a character limit to keep the dashboard performant and visually manageable. In this case, the full body is available via API even if the dashboard shows a truncated preview. This is the most recoverable form of truncation — inconvenient for quick debugging, but not a data loss problem.

Storage cost at scale creates economic pressure on response body retention. A gateway processing millions of events per day retaining full response bodies indefinitely is retaining a lot of bytes. Some gateways truncate at the storage layer — storing only the first N kilobytes of a response — to control storage costs. This is a harder form of truncation: the data is gone, not just hidden behind a UI cap.

Design priority tradeoffs matter too. A platform designed primarily around delivery reliability may have invested its engineering attention in retry logic and routing rather than in full-fidelity observability. The observability layer is good, but "good" and "complete" are different standards.

Knowing which form of truncation you're dealing with — if you encounter it — determines what you can do about it.

Questions to Ask Any Webhook Tool

Before committing any webhook gateway to production, test error storage behavior with your actual application's error shapes — not just clean success cases. The webhook debugging guide outlines a complete pre-production validation process. See HookTunnel features for how full-fidelity storage works in practice.

What is the maximum stored response body size? Ask the vendor or test it by sending a response body larger than 10KB, then 100KB, then 1MB. Check whether the stored content matches what you sent. Many gateways have undocumented limits that only reveal themselves when your application generates large error responses.

Does the UI show the full stored payload, or a truncated preview? Test by sending a response body that's longer than what you can see in the dashboard preview. Then check whether the API endpoint for that event returns the full body. If the full body is in the API but not the UI, you can work around the dashboard limitation — it's annoying but not a data integrity problem.

Can you access raw response bytes via API? For debugging scenarios where you need to be certain you're looking at the exact bytes your handler returned, API access to the raw stored response is valuable. Some gateways provide this; others only expose parsed or display-formatted representations.

How long are delivery attempt records retained? The retry history for an event that failed three weeks ago and was never resolved might be the most important debugging artifact you have for a post-incident review. If delivery records are retained for only 7 days, a slow-burn issue that wasn't noticed immediately loses its paper trail.

Test these behaviors with your actual application's error shape — not just synthetic test cases — before you declare an evaluation complete.

HookTunnel's Approach

HookTunnel stores the complete incoming request and, on replay, logs the complete response from the target. There is no truncation at the storage layer — the full payload, headers, and response body are retained as captured.

On the free tier, this history persists for 24 hours. On Pro ($19/month flat), the history window is 30 days. In both cases, what you see in the dashboard is what was captured — no truncation in the display layer, no UI cap on response body length, no gap between what's stored and what's shown.

Replay returns the target's response in full, so you can see exactly what your handler returned when you replayed an event — useful both for verifying that a replay succeeded and for debugging why it didn't.

This is a narrower capability set than what Hookdeck offers. HookTunnel captures and stores events; it doesn't provide at-least-once delivery guarantees, automated retry policies, or event routing. If you need those capabilities, Hookdeck is the appropriate tool to evaluate, truncation question and all.

But if your primary requirement is complete, long-lived, full-fidelity event capture with no surprises about what's retained and what's displayed, knowing that nothing is being trimmed at the edges matters.

Debugging Tools Should Not Hide Evidence

The standard for webhook infrastructure observability is simple: the data that was transmitted should be the data that's stored, and the data that's stored should be the data that's displayed. Gaps anywhere in that chain extend incident resolution time — sometimes by hours.

Gaps anywhere in that chain — between transmission and storage, or between storage and display — degrade debugging fidelity. Sometimes the gap is small and the impact is manageable. Sometimes the gap is in exactly the part of the error message that would have identified the root cause in thirty seconds instead of thirty minutes.

Check what any gateway stores versus what it displays. Run tests with actual error shapes from your application, not clean success cases. Read the documentation on retention limits. Ask the vendor directly what the stored response body size cap is.

The investment in checking these details before a production incident is small. The cost of discovering a truncation limit during a production incident is not.

Try HookTunnel free → Full payload capture, complete response storage, 24-hour history at no cost, 30-day history on Pro.