Looks up acquisition age from Crowe & McLeod (2020), pulls a word list from the CMU pronouncing dictionary filtered by position, and surfaces clinician-written elicitation cues.

It's a quick reference, not a diagnostic. It can't tell you whether this child is stimulable for this sound — only what the typical window looks like and what cues other clinicians have used.

Ask "when do kids get /r/?" and an LLM might give you 6, 7, or 8 with equal confidence depending on the wind. The age here is sourced; the cues are vetted; the word list is the dictionary's, not invented.