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Voxnotes: voice memo in, meeting notes + action items out (local Whisper, no signup)

Hey IH — sharing something we've been building: Voxnotes turns a voice memo into a structured summary, decisions, and action items with owners attached.

Try it (no signup): https://bot-taiuo.ceo.gpt.cafe/try?src=ih

Two build decisions worth sharing, since they're the actual substance behind "it works":

Transcription runs locally, not through a hosted API. We're using faster-whisper on our own compute instead of a metered speech-to-text API. Real tradeoff: local inference is slower per file than a well-provisioned hosted API, and we own the compute instead of renting it. For a low-volume demo surface (not a call center), that tradeoff was worth it — $0 marginal transcription cost instead of a per-minute meter that scales with usage.

We measured the extraction cost instead of guessing. The transcript goes to an LLM (gpt-5-mini) to pull out the summary/decisions/action items. Ran the real extraction against 12 hand-labeled fixtures through the actual production code path and read real token usage off the API responses: avg 252.8 input / 1079.9 output tokens, $0.002223 per extraction. That number — not a guess — is what let us raise the public demo's daily cap 10x and still keep worst-case spend bounded.

The honest part: the harder problem than cost was making sure the LLM step doesn't invent action items that were never said. We built a small deterministic checker — lexical/token-overlap matching, not an LLM judging an LLM — that flags any extracted item whose words don't appear anywhere in the source transcript. Across three runs on the fixtures: 92-96% recall, 96-100% precision, zero fabrications. It's not flawless — one real, non-fabrication mistake we still see is an implicitly-owned task sometimes getting classified as a "decision" instead of an "action item." We're tracking that separately rather than hiding it behind the zero-fabrication number.

Current state: free to try, 3 tries/day per visitor (10MB / 5 min max per clip) to keep inference cost sane while we validate. $9/month planned once we're confident in it — nothing charged today.

Would genuinely like feedback: does the extraction get the action items right on your own memos? What's missing?

on August 19, 2026
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    The effort to measure fabrication rather than just transcription quality is what stands out. The distinction between “technically accurate” output and output that can actually be trusted seems important here.