Best Free Online Developer Tools to Use in 2026
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Aug 08, 2026
3xx Redirection
The 300 (Multiple Choices) status code indicates that the target resource has more than one representation and the user or user agent can choose a preferred one. The server may include a list of available representations in the response body. This is rarely used in practice — most servers choose one redirect target automatically.
If your API serves a document in both JSON and XML formats and the client does not specify a preference via Accept headers, you could return 300 Multiple Choices with links to each variant. In practice, most APIs default to one format and use content negotiation transparently.
HTTP/1.1 300 Multiple Choices
Content-Type: text/html
<html><body><ul>
<li><a href='report.json'>JSON</a></li>
<li><a href='report.xml'>XML</a></li>
<li><a href='report.csv'>CSV</a></li>
</ul></body></html>
Mistake: Using 300 instead of transparent content negotiation
Fix: Modern APIs should use content negotiation via Accept headers to automatically select the best representation, returning 200 OK with the chosen format. 300 forces the client to make a manual choice, which degrades user experience.
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