Is it appropriate for me to request part of my agent's commission if I bring the buyer?

[ca_surveyor]

If you have an exclusive agreement with your selling agent, then you have agreed, in writing, that only that person has the right to list and sell the house. THAT INCLUDES YOU unless you specified differently.

You could do ALL Of the work, but unless your contract gives you the right to sell it yourself (also) you will still have to abide by what you signed.

You are better off to talk to the real estate agent NOW about this... you have a bit of leverage available to you at this point, but if she presents you with a signed offer for the sale amount.. no matter HOW that buyer found out, you will owe the commission and at that point it is unlikely you will get the agent to alter the agreement.