SaaS Integration & Backend Tools
Free browser-based tools for SaaS developers and backend engineers. Debug API requests, test webhook payloads, inspect authentication headers, and analyze query strings and cookies — without leaving your browser.
3 tools covering API debugging, webhook testing, request inspection, and client analysis.
What This Domain Covers
SaaS integrations live and die by the quality of your request debugging workflow. When a webhook fails silently, when an API returns an unexpected payload, or when a cookie is missing an attribute that breaks authentication — the gap between encountering the problem and understanding it is usually tooling. The tools in this cluster close that gap.
- •API request and response debugging
- •Webhook testing and payload inspection
- •Authentication and token handling
- •Header, cookie, and query string parsing
- •Integration troubleshooting workflows
API Request & Response Debugging
The API Response Formatter takes a raw API response — JSON, XML, or plain text — and pretty-prints it with syntax highlighting and a collapsible tree view. The Query String Parser decodes URL-encoded query parameters from a full URL or a raw query string, showing each key-value pair clearly. Both tools run entirely client-side, so you can safely paste production responses and internal API payloads.
For cookie-based authentication debugging, the Cookie Parser decodes the Cookie or Set-Cookie header into structured fields, flagging missing HttpOnly, Secure, and SameSite attributes. See the API and Webhook Integration guide for a full debugging workflow.
Webhook Testing
The Webhook Tester generates a unique URL that accepts any HTTP method. Paste it into the webhook configuration of Stripe, GitHub, Shopify, Twilio, or any other service — then send a test event. The tool captures the full request: headers (including signature headers), HTTP method, timestamp, and body. JSON payloads are automatically formatted. Sessions are temporary and expire after one hour.
For background on the trade-offs between webhook-based and polling-based integrations, see Webhooks vs Polling.
SaaS Integration Tools
Browser-based tools — no installs, no uploads, no data stored on our servers.
Request & API Debugging
Parse and inspect every component of an HTTP request — format API responses, decode query strings, and analyze cookie headers. All parsing runs client-side.
API Request Building & Debugging
Build HTTP requests with custom methods, headers, query params, and body modes. Send directly from your browser via fetch(), inspect the response, and export a cURL command for terminal replay. Ideal for testing API integrations without Postman.
Payload Inspection & Diffing
Compare two webhook JSON payloads to identify added, removed, and changed fields. See exact field paths and old/new values. Browser-only — no data sent to a server.
SaaS Integration Guides & Comparisons
In-depth reference pages on API patterns, webhook architecture, and integration trade-offs.
Guides
A practical guide to API and webhook integrations — request-response vs event-driven patterns, debugging API calls, inspecting webhook payloads, common integration mistakes, and the tools that make it faster.
A practical guide to debugging webhook integrations — common failure modes, step-by-step inspection workflows, logging strategies, and the tools that make it faster.
A step-by-step guide to diagnosing API request failures — from reading status codes and inspecting headers to reproducing errors with cURL and fixing CORS, auth, and payload issues.
Webhook senders retry on failure — your handler will receive the same event more than once. Covers how retries work, deduplication strategies, and how to design idempotent webhook handlers.
Comparisons
Webhooks push events to your server in real time; polling pulls data on a schedule. Compare efficiency, reliability, complexity, and use cases to choose the right integration pattern for your SaaS.
REST is simple and cacheable; GraphQL eliminates over-fetching with precise queries. Compare flexibility, caching, complexity, and real-world use cases.
Webhooks push events to an external HTTP endpoint in real time; message queues buffer events internally for reliable async processing. Compare delivery model, retry behavior, ordering, failure recovery, and use cases.
Webhooks push HTTP callbacks to a single endpoint; event streaming platforms (Kafka, Kinesis, Pub/Sub) persist events in a durable log for multiple consumers. Compare delivery model, ordering, fan-out, replay, and complexity.
Frequently Asked Questions
What is a webhook and how does it work?
A webhook is an HTTP callback — when an event occurs in a source system (e.g., a payment is completed in Stripe, a push is made in GitHub), the system sends an HTTP POST request to a URL you provide. Your server receives the request, parses the payload, and takes action. Webhooks are the primary integration pattern in SaaS: they deliver data to your system in real time without polling.
How do I debug an API request without running my server?
Use the API Response Formatter to pretty-print and inspect a raw API response payload. For the request components, use the Query String Parser to decode URL-encoded parameters, the Cookie Parser to decode the Cookie or Set-Cookie header, and the HTTP Header Analyzer to categorize and audit all request headers. All tools run locally in your browser — paste the raw values and inspect immediately.
What's the difference between webhooks and polling?
Polling is when your system periodically sends GET requests to check for new data — simple to implement but inefficient for real-time needs. Webhooks are event-driven: the source system pushes data to your endpoint the moment an event occurs. Webhooks are lower latency, more efficient, and the standard pattern for SaaS integrations. See the full comparison at Webhooks vs Polling.
How do I test a webhook endpoint before connecting a live service?
Use the Webhook Tester tool. It generates a unique URL you can paste into Stripe, GitHub, Shopify, or any service that lets you configure a webhook endpoint. When the service sends a test event, the Webhook Tester captures the full request — method, headers, and body — so you can inspect the payload structure before writing your handler.
How do I inspect request headers in my integration?
Copy the raw headers from your API client, browser DevTools Network tab, or curl output, then paste them into the HTTP Header Analyzer (in the DevOps cluster). It categorises headers (authentication, content, caching, security, CORS), explains each one, flags missing security headers, and warns about suspicious values like wildcard CORS origins.
What tools help debug authentication issues in API integrations?
For cookie-based authentication, use the Cookie Parser to decode the Cookie header and check attributes like HttpOnly, Secure, and SameSite. For JWT bearer tokens, the JWT Decoder (in the API domain) decodes the header and payload without verifying the signature. For API key and OAuth integrations, the API Response Formatter helps you inspect error responses from the auth server.
Is it safe to paste production payloads into these tools?
For the browser-based tools (API Response Formatter, Query String Parser, Cookie Parser, User-Agent Parser), yes — all processing runs locally in your browser. No data is transmitted or stored. For the Webhook Tester, payloads are temporarily stored in server memory for up to 1 hour to enable real-time display; they are not written to a database or shared.