Ever stumbled upon mysterious API error codes like 102, 103, or 104 while integrating a service or debugging a live app?
You’re not alone.
These error codes can appear in a variety of applications—whether you’re connecting to payment gateways, authentication systems, or third-party APIs. And while they seem cryptic at first glance, they each have specific meanings that can help you pinpoint what went wrong and how to fix it.
In this guide, we’ll break down:
- What API Error 102, 103, and 104 typically mean,
- Real-world causes and when they usually appear,
- How to resolve them efficiently with clear, actionable steps.
Let’s decode them, human-style.
What Is API Error 102?
Definition:
API Error 102 is most commonly interpreted as a processing or parameter-related error depending on the context of the API provider.
There are two main types of this error:
Type 1: HTTP 102 (Processing)
- This is a 1xx informational status code.
- It means your request has been received and is still being processed, but no final response is ready yet.
- Most common in WebDAV servers or systems that require extended processing time.
What You Should Do:
- Wait for a final response (like 200 OK).
- Do not retry or abort unless the response stalls for an unusually long time.
- Make sure your client or SDK supports 1xx responses.
Type 2: API-Specific 102 Error
In many APIs (like messaging platforms, payment gateways, etc.), Error 102 means:
“Missing or invalid request parameters.”
How to Fix:
- Double-check required parameters (especially ones like
api_key,username,amount, orrecipient). - Validate field types and formats (e.g., email syntax, currency format).
- Use Postman or a REST client to test the request independently before integration.
🧠 Insight:
Error 102 often appears early in the request lifecycle—fixing it is usually about checking your input thoroughly, not the backend logic.
What Is API Error 103?
Definition:
Error 103 is usually linked to invalid input fields, unsupported functions, or malformed security data.
It can also appear during authentication or payment processing, especially when:
- A CVC/CVV field is the wrong length,
- A route or function doesn’t exist in the API version you’re using,
- You’re calling an endpoint incorrectly.
Real Use Case:
- In payment APIs, “Error 103” may mean:
“CVC is not the correct length”
Double-check whether the card type expects 3 or 4 digits.
- In user management APIs, it might show:
“Invalid API function”
This means you called an endpoint that doesn’t exist (or has been deprecated).
How to Fix:
- Re-read the API documentation and validate function names or endpoint routes.
- For card-related operations, validate field length and data types in client-side forms.
- Confirm you’re using the correct HTTP method (GET vs POST vs DELETE).
🧠 Unique Insight:
API Error 103 is the most overlooked error, because it often feels like “the code is correct.” But it’s usually a mismatch between what the client sends vs. what the API expects.
What Is API Error 104?
Definition:
Error 104 is typically associated with route not found, missing resource identifiers, or incomplete field entries.
Depending on the API you’re using, it might look like:
- “Route not found”
- “Missing billing address”
- “User ID not provided”
When Does It Happen?
- When your endpoint URL is misspelled or not supported.
- When your request lacks a required field like
user_id,billingAddress, ortransactionId. - When you’re trying to access an API version that’s no longer supported.
How to Fix:
- Ensure your request path matches the API documentation exactly.
- Double-check that all required fields (especially nested objects) are included and non-empty.
- If using a dynamic endpoint (e.g.,
/users/:id), ensure you’re passing an actual ID, not just:id.
🧠 Unique Insight:
Error 104 usually boils down to miscommunication between client and server about where or what you’re trying to access. Fixing it is more about structure and syntax than business logic.
Quick Fix Summary Table
| Error | What It Means | How to Fix It |
|---|---|---|
| 102 | Request in progress / missing parameters | Wait for response or validate required fields |
| 103 | Invalid field/function / wrong CVC format | Check parameter names, function availability, or data format |
| 104 | Missing route, field, or resource identifier | Ensure endpoint exists and all required data fields are included |
Pro Tips to Prevent These API Errors
- Validate before you send: Use frontend validation and schema checks to catch missing fields early.
- Read API changelogs: APIs evolve. A previously working endpoint might be deprecated or changed.
- Use detailed logging: Log request payloads and responses with timestamps and error messages.
- Build sandbox testing: Use staging environments to test integrations before pushing to production.
- Don’t hard-code: Use environment variables or dynamic request generation to prevent typos.
Frequently Asked Questions (FAQs)
Q1: Are API error codes universal?
Not entirely. While HTTP codes follow a standard, custom API codes like 102–104 depend on the service provider. Always refer to their docs.
Q2: What should I log when debugging API 103 or 104?
Log the exact endpoint, the full request payload, and the error message returned by the API. Include headers and tokens (excluding secrets) if necessary.
Q3: Can I ignore HTTP 102 responses?
Yes, they’re informational. However, your client should still be able to handle them gracefully without crashing.
Q4: Why do I still get API errors even if my request looks fine?
You might be missing subtle issues like incorrect headers, API version mismatch, or using a wrong HTTP method. Always cross-reference with documentation and test tools like Postman.
Q5: Can these errors cause transaction failures?
Absolutely. In financial APIs, a bad parameter (103) or missing billing info (104) can block the transaction entirely. Never skip input validation.
Final Thoughts
API errors like 102, 103, and 104 may look minor, but they’re essential checkpoints for building reliable, scalable applications. Understanding what they mean—and how to fix them fast—can save you hours of troubleshooting.
Treat these errors not as blockers, but as conversation starters between your code and the services you’re using.
Now that you’ve decoded them, your next integration just got a whole lot smoother.