When submitting to a publication, avoid phrases like “I have the perfect article for you.” You may. But editors have a better idea of the perfect article for their readers—even if they don’t know it’s yours till it’s in their hands. In other words, you may have written that story, but don’t sound like you know a publication’s audience or editorial plans better than the editor does.
If you’ve written the article—an essay, for instance, which it’s better to submit complete, because with a piece like that it’s all in the execution—send it with a brief description. Mention previous publications, sure, but don’t send links to clips; the essay will speak for itself.
If it’s a pitch for a reported story, keep the query to a few paragraphs describing what you want to write, whom you’ll talk to, what you know so far, and an idea of length, along with—in this case, yes—clips. End with something like “I hope you’ll agree...” Then let the editor get back to you with how he or she envisions the article—maybe shorter, maybe longer, maybe focusing on just one angle.
Or maybe, in fact, precisely as you described it.