is commonly used
is significantly differentiated from all other "typical" status codes (i.e., there should never be more than one plausible choice of which code to return)
programmers are expected to have it memorized.

These constraints impose a natural limit on how many "typical" status codes you can have.

A certain list of "typical" status codes is a config parameter. By default it includes:

200, 204
- Notes: 201 is disallowed. Use 200 instead
302
- Notes: all other 300-series are situationally valid, as they directly affect browser / cache behavior, but are less frequently used in JSON APIs. For this reason, http.Redirect() calls are exempt from the "restrict" rule.
400, 401, 403, 404, 429
- 409, 410 and 422 are disallowed; use 400 instead.
- Notes: explicit 405 is disallowed; router should return one automatically
502, 504
- Notes: explicit 500 is disallowed. Use panic instead
All other status codes are considered "non-typical"

Status codes in the "typical" list require use of "magic numbers" (the opposite of staticcheck's ST1013 check, on purpose); using http.StatusBlahBlah is disallowed. Only non-typical status codes are permitted to use the named net/http constants. "Magic numbers" are shorter and-- for typical status codes-- more readable.

If the optional "restrict" config value is set to "true", then setting non-typical status codes in HTTP handlers is also disallowed. As noted above, http.Redirect() and the 300-series is exempt from this.

Implementation clarifications

Check every reference to a net/http Status* constant, regardless of context. A typical constant is disallowed even in a declaration such as const ok = http.StatusOK.
Inspect only status codes supplied to http.Error and the WriteHeader method declared by http.ResponseWriter. Do not inspect fixed-status helpers such as http.NotFound() or ResponseWriter.Write().
Do not diagnose a runtime value such as w.WriteHeader(code) when code is a variable.
With restrict: true, reject statically known non-typical codes passed to http.Error or http.ResponseWriter.WriteHeader.
http.Redirect is exempt from restrict for 300-series codes. Its use of a named typical net/http status constant remains disallowed by the general constant rule.
A configured typical-status-code list replaces the default list.