ConceptSeek

The framing on the site — "an instrument, not an assistant" — is not marketing garnish, it describes the actual product behavior, and it's the reason to pick this over the crowded field of document summarizers. Every capability shown on the homepage is about returning you to the source: concept search surfaces passages where the idea is present even if the wording differs; Jump to moment opens the exact timestamp with transcript and video in sync; the auto-scroll library view keeps you moving through matched moments inside a single source. Threads is the differentiator worth the trial. It renders your library as a map of connections — 17 sources, 56 connections in the homepage example — and tags each relationship as agrees, contradicts, complements, or different context. For a journalist testing whether two podcast hosts actually disagree, or a student checking whether three papers converge, that labeled structure is more useful than any summary, because you can see the shape of the disagreement before you read a word of it. Libraries and saved searches turn this into a durable research asset: you name a library, you add sources over time, you save "Pageau · Jacob · Apr 26" and come back to it when new material arrives. Cross-library search with an all/none scope selector means you can point one query at 1 of 8 libraries or all of them without losing which source a hit came from. The constraints are real and you should price them before you commit. Usage runs on credits — 1,000 a month on Starter, 3,000 on Pro, 10,000 on Max — and the homepage itself shows searches consuming credits ("-10 credits" appears in the interface previews), so a heavy comparer will feel the ceiling. Sources per library are capped at 20, 80, and 500 across the three tiers, and cross-library search on Starter reaches only 2 libraries. A researcher maintaining five topic libraries of 60 sources each is not a Starter customer; they're a Pro or Max customer. The other structural fact is the one the vendor states plainly: ConceptSeek is built by an independent developer without a team or investors. That buys you a tool that doesn't chase enterprise contracts and a $25 one-time supporter option, and it also means you should treat continuity as a consideration if this becomes load-bearing for a dissertation or an investigation. Where it fits: any workflow where the value is in the passages, not the gist. Literature review, evidence comparison, recovering an idea you remember but can't phrase, mapping a debate across many episodes. Where it doesn't: if you want an assistant to write, summarize, or draft, this tool will actively refuse the job — it returns material and leaves the thinking to you. Teams are also out of scope; this is a personal research instrument, not a shared workspace. Treat the 7-day free trial on every plan as a capacity test: load your real sources at real volume and watch the credit counter before you choose a tier.