Turn messy documents into accurate answers in seconds
Lumen indexes your Drive, Notion and Slack, then answers questions in plain English. Every answer arrives with the file, page and paragraph it came from — so your team can verify in one glance.
No credit card required · 2 minute setup
- docs indexed daily
- 12kdocs indexed daily
- average team rating
- 4.9/5average team rating
- teams onboard
- 80+teams onboard
What notice period do we owe Acme if we terminate early, and does the pricing exception still apply?
You owe Acme 60 days' written notice for early termination, delivered to their registered address.[1]
The 12% volume discount agreed in March does not survive termination — it is tied to the committed annual volume in the order form.[2]
Trusted by operators at
- Fernwood
- Northbeam
- Kestrel AI
- Havenly
- Orbit Legal
- Pinehill
Your company already wrote the answer. Nobody can find it.
The documents exist. They're just spread across four tools, three naming conventions and one person who remembers where everything is.
1.8 hrs
Lost every day to searching
Knowledge workers spend nearly a quarter of the week hunting for information they already own.
7 pings
The same question, again
Answers live in one person's head. When they're on holiday, the team stalls.
40%
Docs already out of date
Copies drift. Somebody quotes a policy that was changed in a Slack thread eight months ago.
3 weeks
Onboarding by shadowing
New hires learn by interrupting senior people instead of reading what already exists.
Everything you need to trust an AI answer
Six things that separate a useful document assistant from a party trick.
Ask any document
Point Lumen at a 400-page contract or a folder of messy meeting notes and ask in plain English.
Try: "What is the notice period in the Acme MSA?"
Source-backed answers
Every sentence links to the file, page and paragraph it came from, so nobody has to trust a black box.
Answer cites: MSA_v4.pdf · p.12 · §7.3
Team knowledge base
Shared workspaces keep answers consistent. New hires ask the docs instead of interrupting seniors.
Onboarding questions dropped 61% at Fernwood
Connect Drive, Notion, Slack
Sync in one click and Lumen re-indexes on change. No exports, no nightly CSV jobs, no stale copies.
14 connectors, incremental sync every 5 minutes
Secure by default
Per-source permissions mirror your existing access rules. Encrypted at rest, SOC 2 Type II, EU hosting option.
If they can't open the file, they can't query it
API + embeddable chat
One REST endpoint for answers with citations, plus a drop-in widget you can ship inside your own product.
POST /v1/answers → { text, citations[] }
Live in under fifteen minutes
No data warehouse, no migration project, no consultant. Connect, index, ask.
- 01
Connect sources
Authorise Google Drive, Notion, Slack, S3 or upload files directly. Permissions are inherited, not re-invented.
~2 minutes
- 02
Index knowledge
Lumen parses tables, scans, and screenshots, chunks by meaning rather than character count, and embeds it all.
~8 minutes for 1,000 docs
- 03
Ask and cite
Your team asks questions in the app, in Slack, or through the API — and gets answers with receipts attached.
Median response 1.4s
This is what an answer looks like
A real question against a real contract, with the sources panel open. No hidden reasoning, no unverifiable claims.
What notice period do we owe Acme if we terminate early, and does the pricing exception still apply?
You owe Acme 60 days' written notice for early termination, delivered to their registered address.[1]
The 12% volume discount agreed in March does not survive termination — it is tied to the committed annual volume in the order form.[2]
Answers you can audit
Each claim is highlighted and numbered. Hovering a citation scrolls the source panel to the exact passage.
Retrieval scores in the open
We show how strongly each source matched. Weak evidence looks weak instead of hiding behind confident prose.
Everything in one thread
Follow-ups keep context. Threads can be saved to the workspace so the next person doesn't ask again.
Same engine, four very different jobs
Teams start with one painful question category and expand from there.
SaaS support teams
Draft replies grounded in your real help centre, changelog and past tickets.
- Deflect repeat tickets
- Consistent tone
- Cite the doc in the reply
Legal & ops
Find the clause, the renewal date, or the policy exception without opening twelve PDFs.
- Clause lookup
- Obligation summaries
- Redline context
Sales enablement
Reps get battlecard-quality answers mid-call, pulled from decks and win/loss notes.
- Objection handling
- Pricing rules
- Competitor deltas
Founders & internal docs
Your Notion is a graveyard. Lumen makes it answer questions instead of collecting dust.
- Onboarding Q&A
- Investor update source data
- Process recall
What teams say after month two
The honeymoon-period reviews are easy. These are from teams that kept paying.
“We had four years of support macros scattered across Notion and Google Docs. Lumen indexed all of it on a Tuesday and by Friday our first-reply time was down 38%.”
“The citation panel is the part that sold my legal team. They don't want a chatbot, they want a clause with a page number. That's exactly what they get.”
“I asked it what our refund policy was for annual plans. It quoted the policy, the exception we agreed in 2024, and the Slack thread where we changed our minds.”
“Onboarding used to mean shadowing me for two weeks. New reps now ask Lumen and only escalate the weird stuff. I got my mornings back.”
“We shipped the embeddable widget into our own dashboard in an afternoon. The API returns citations as structured JSON, which saved us building a parser.”
“It's the first internal tool people actually use unprompted. The honest 'I couldn't find this' response builds more trust than a confident wrong answer.”
Priced per workspace, not per question
Nobody should ration questions. Pick a plan on document volume and seats instead.
Yearly billing includes two months free.
Starter
For one person testing Lumen on a real folder of documents.
$0forever
Start free- 1 workspace, 1 seat
- 200 documents indexed
- 300 questions / month
- Drive + file uploads
- Citations on every answer
- Community support
Pro
For operators and small teams who live in their docs all day.
$29/ month
Start 14-day trial- 5 seats included
- 5,000 documents indexed
- Unlimited questions
- Drive, Notion, Slack, S3
- Answer history & saved threads
- API access (10k calls / mo)
- Email support, 1 business day
Team
For knowledge teams that need permissions, audit trails and scale.
$79/ month
Talk to us- 20 seats, then $6 / seat
- 50,000 documents indexed
- Permission-aware retrieval
- SSO / SAML + audit log
- Embeddable chat widget
- Unlimited API calls
- Shared Slack channel
Cancel anytime · Prices in USD, excluding VAT
Questions people actually ask
Still unsure? Email us and a human replies within a business day.
Lumen is a document intelligence tool for teams. You connect the places your knowledge already lives — Drive, Notion, Slack, S3 or direct uploads — and Lumen indexes it so people can ask questions in plain language and get an answer with sources attached.
Always. Every claim in an answer is linked to the file, page and paragraph it was drawn from, and the sources panel shows a retrieval score for each one. If Lumen can't find supporting text, it says so rather than guessing.
That's the whole point. Lumen only answers from the documents you connect. PDFs (including scans), DOCX, PPTX, Markdown, HTML, CSV and Notion pages are all supported out of the box.
Yes. A single POST /v1/answers endpoint returns the answer text plus a structured citations array. Pro includes 10,000 calls per month; Team is unlimited. There's also a drop-in chat widget you can embed in your own product.
Starter is free forever for one person and 200 documents. Pro is $29/month and Team is $79/month, billed per workspace rather than per question. Choose yearly billing and you get two months free. Cancel anytime from the billing page.
Yes — every paid plan includes commercial use, and the template you're looking at right now ships with a licence that allows unlimited personal, client and commercial projects.
No. Your documents and questions are never used to train models, ours or anyone else's. Data is encrypted in transit and at rest, retention is configurable, and EU-only processing is available on Team plans.
Edit src/lib/site.ts for brand, copy and CTAs; the other files in src/lib for features, pricing, testimonials, FAQ and blog posts; and the token block at the top of src/app/globals.css for colours and fonts. See docs/customization.md for the full walkthrough.
Can't find it? Ask us directly.
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