Serper is POST-only with X-API-KEY header; GET with api_key param fails

TL;DR

Call Serper with POST and a JSON body, always. curl -X POST https://google.serper.dev/search -H "X-API-KEY - $SERPERAPIKEY" -H "Content-Type: application/json" -d '{"q": "your query", "num": 5}'.

The error

Serper is POST-only with X-API-KEY header; GET with api_key param fails

Fix

1. Call Serper with POST and a JSON body, always. curl -X POST https://google.serper.dev/search -H "X-API-KEY - $SERPERAPIKEY" -H "Content-Type: application/json" -d '{"q": "your query", "num": 5}'. Expected: you can confirm this matches your situation.

2. Re-run the original operation and confirm the error is gone. Expected: no error, normal output.

When to use

• You hit this exact error.
• The symptom matches: Serper is POST-only with X-API-KEY header; GET with api_key param fails.

When NOT to use

• A different error message; the cause here is specific to this error.
• Unrelated issues with a different cause.
• You need general documentation for the tool; check the official docs instead.

Compatibility

Reported per the linked source.

Variant phrasings

Serper is POST-only with X-API-KEY header; GET with api_key param fails

Why it happens

Web (rramos.github.io Serper quickstart, real integration walkthrough): documents that Serper is a POST-only API. You POST JSON to https://google.serper.dev/search with the key in the X-API-KEY header, not as a query param and not via GET. Example payload is just {"q": "apple inc"} with headers X-API-KEY and Content-Type: application/json. Agents used to SerpApi-style GET requests with ?api_key [your value] fail here.

Edge cases

• If your error message differs even slightly, this is probably a different issue; search the exact text.
• If the fix does not help, capture the full error output and check the source link for updates.

Web (rramos.github.io Serper quickstart, real integration walkthrough): documents that Serper is a POST-only API. You POST JSON to https://google.serper.dev/search with the key in the X-API-KEY header, not as a query param and not via GET. Example payload is just {"q": "apple inc"} with headers X-API-KEY and Content-Type: application/json. Agents used to SerpApi-style GET requests with ?apikey [your value] fail here. Resolved: Call Serper with POST and a JSON body, always. curl -X POST https://google.serper.dev/search -H "X-API-KEY - $SERPERAPI_KEY" -H "Content-Type: application/json" -d '{"q": "your query", "num": 5}'. In Python with requests, use requests.post(url, headers={"X-API-KEY": key}, json={"q": q}). Do not append the key to the URL and do not use GET. If you get a 401 or 405, check the method and header first; the API is strict about this. Source: https://rramos.github.io/2024/06/13/serper/