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Developer

API Client

Browser-Only

Test REST and GraphQL APIs in your browser. Direct or proxy send, collections, auth, cURL import, and code generation — free, no download.

By default, collections and drafts stay in your browser. Proxy mode sends the HTTP request you choose through Tool Reign’s relay (not stored or logged). The page says so before first use.

How to Use

Step-by-step guide to get the most from this tool

  1. 1

    Enter URL and method

    Choose GET/POST/…, paste the URL, and pick Direct, Proxy, or Auto.

  2. 2

    Add params, headers, body, auth

    Use the tabs for query params, headers, raw/form/GraphQL body, and Bearer/Basic/API Key/OAuth client credentials.

  3. 3

    Send and inspect

    Press Ctrl/Cmd+Enter. Review body, headers, cookies, timing, and generate client code.

  4. 4

    Save and import

    Save to a collection, import cURL or OpenAPI, and backup your workspace.

Features

What makes this tool stand out

🔀

Direct / Proxy / Auto

Browser fetch or Tool Reign relay with consent for CORS.

📁

Collections & history

Folders, save/restore, last 100 history entries in IndexedDB.

🔐

Auth & variables

Bearer, Basic, API Key, OAuth client credentials, {{vars}} and dynamics.

📥

Import / export

cURL, collection JSON v2.0/v2.1, OpenAPI 3.x; export cURL and collections.

💻

Code generation

cURL, fetch, Python, PHP, Go, C# with optional variable resolution.

🔒

Private by default

Data stays in your browser unless you choose Proxy and consent.

How it works

What happens under the hood — and how to use it well

Requests run from your browser in Direct mode. Proxy mode (optional, with consent) relays URL, headers, and body through Tool Reign’s server without storing them — localhost and private IPs stay Direct-only.

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💻
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{}
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🔍
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🔑
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Decode JWT tokens

Frequently Asked Questions

Quick answers to common questions

Why do I get a CORS error in Direct mode?+

Browsers enforce CORS. If the API does not allow your origin, Direct mode fails. Switch to Auto (retry via proxy after consent) or Proxy, or ask the API owner to allow browser origins.

What is the difference between Direct and Proxy?+

Direct sends the request from your browser to the API. Proxy relays the request through Tool Reign’s server so CORS does not apply. Proxy cannot reach localhost or private IPs.

What does the proxy see?+

When you use Proxy (or Auto after consent), the URL, headers (including Authorization), and body are sent to Tool Reign’s relay to fetch the target. They are not stored or logged. Prefer non-production credentials.

Why does localhost fail via Proxy?+

The proxy blocks loopback and private addresses by design (SSRF protection). Use Direct mode for local APIs.

What are the size and time limits?+

Proxy limits come from /v1/config (request/response bytes, timeout, redirects). Direct mode is limited by your browser and the API. Oversized responses may be truncated.

Where is my data stored?+

Collections, history, environments, and tabs are stored in IndexedDB in your browser (migrated from older localStorage keys). Use Backup/Restore to move data. History redacts secrets by default.

Why are some headers forbidden in Direct mode?+

Browsers forbid setting Cookie, Host, Referer, Connection, and similar headers from JavaScript. The tool warns you inline. Proxy mode can send those headers upstream.

How do cookies work?+

In Direct mode, Set-Cookie from cross-origin responses is usually unreadable. In Proxy mode, a session cookie jar can store and replay cookies per domain.

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