crux

Status: pre-launch, private beta, for Windows.

Bid due tomorrow? Done tonight.

AI estimating for general contractors. crux reads the whole bid set in 10 to 30 minutes, not four to five hours. It cites every answer, turns conflicts into RFIs, levels sub quotes and builds the estimate in your own template. Add-on packs cover specialty subs, starting with painting.

Reads every sheet so you don't have to. An AI agent reviews every drawing and spec page, and every answer is cited back to the source.

Runs on your computer. Your bids never touch our servers.
GC seat $6,990/yr · subcontractor seat $3,990/yr

The crux Documents page for a sample GC bid: the bid due to the owner, the questions deadline and addenda, and a Needs you card on flooring, where no invited sub has committed: call the subs first, or budget it from company history. The crux Documents page for a sample GC bid: the bid due to the owner, the questions deadline and addenda, and a Needs you card on flooring, where no invited sub has committed: call the subs first, or budget it from company history.
The Documents page: the bid dates, and the decision crux needs from you, with its sources.crux app · sample job
Project
crux
Sheet
A-000 · Cover
Title
project intelligence
Status
Private beta

Watch

Bid due tomorrow? Watch it get done.

One sample GC bid on a public bid set: point crux at the job folder, every page read and indexed, a drawing conflict caught and turned into an RFI, a takeoff checked against the plans, sub bids leveled, and what to carry to win. Every answer cited.

crux for general contractors, on a sample bid.Demo video · 1:42

01 · What crux does

GC estimating, from the bid set to bid day, in one app.

crux does the reading, cross-checking and paperwork that eats a GC estimator's week, and it shows its work. crux reads the bid set while you keep working, so you can bid several projects at once. Every quantity and every claim points back to the sheet, spec section or addendum it came from, so you can check it in seconds.

Agentic workflows grounded in your documents: the AI agent does the reading, checking and drafting, and you approve what it finds.

A

Reads the whole bid set

Specs, drawings, addenda and the bid form. crux indexes every page, writes the executive summary and a scope review for every trade, and cites each fact to its sheet, section or addendum item.

SpecsA-611Bid form
B

Turns conflicts into RFIs

When the spec and the drawings disagree, or the bid set leaves something out, crux shows both sources, says which one governs when the documents settle it, and drafts the RFI when they don't.

Draft onlyYou send
C

Levels the sub quotes

Each quote is checked item by item against the scope checklist. What a bidder left out is plugged from another bidder's printed breakout, marked and cited, so the leveled totals compare like with like.

Scope checklistPlugs cited
D

Writes the scope letters

One letter per trade package, on your letterhead: a bid form the sub returns, the work included, alternates and breakouts, and what's by others, each item tied to its section or sheet.

Your letterheadBid form
E

Tracks every addendum

Each addendum is logged against the sheets and sections it changes, with what that means for each trade and for your number. Ask for a Current Set and crux builds a copy of the drawings and specs with every change applied and marked with revision clouds. It takes a while and uses credits, so crux asks first.

Addendum 02Supersedes A-611
F

Takes off and builds the estimate

Quantities come from the drawings' vector geometry, never from a picture. crux carries them, the leveled sub numbers and your general conditions into your own estimate workbook. Prices you haven't confirmed are flagged budget-grade.

Your templateBudget-grade flag
G

Makes the bid / no-bid call

Before you spend a week on a bid, crux checks it for fatal flaws, like bonding, the schedule, liquidated damages or a building type you don't build, then scores it against your company's own fit. Every reason points to its page.

Fatal flawsYour fit
H

Carries the win into the job

Won it? crux builds the submittal register from the specs, preps you for the precon and OAC meetings, scans the contract for risk, and pulls the job's RFIs, submittals and drawings from Procore.

SubmittalsProcore
Also in the box Calendar: bid dates and job meetingsWin-loss logCall intake

Your tools Settings · Connectors

Your rates, templates and connectors, in one place.

Your rates, your templates and your company's history live in Settings. Upload a spreadsheet or tell crux what to change in plain words; you see every change before it's saved.

BuildingConnected and Procore stay off until you turn them on here. Each estimator signs in as themselves.

crux Settings, Connectors: BuildingConnected switched on and connected, with its sign-in, and Procore switched on, connected and described as read-only. crux Settings, Connectors: BuildingConnected switched on and connected, with its sign-in, and Procore switched on, connected and described as read-only.
Settings · Connectorscrux app · sample company

02 · How it works

Bid set, sub bids, leveling, estimate. Every number traceable.

One sample GC bid, followed from the bid set to the number. These are screens from the crux app itself; the company, its subs and the project are made up.

02.1 Bid documents

Load the bid set. crux reads all of it.

Drop in the project manual, drawings, addenda and bid form. crux indexes every page, writes the executive summary and a scope review for every trade, notes what each addendum changed and keeps it all in your Binder.

Every fact crux reports carries its source, down to the sheet or the spec paragraph. Click a pill to see the page.

The crux Binder: the sample job's executive summary with the bid date, bonds, wage rates, liquidated damages and the risks to watch, each linked to its spec section, sheet or addendum item. The crux Binder: the sample job's executive summary with the bid date, bonds, wage rates, liquidated damages and the risks to watch, each linked to its spec section, sheet or addendum item.
Binder · executive summarycrux app · sample job

02.2 Conflicts

Spec says one thing, the drawings another. crux shows both.

Ask in plain words. crux checks the spec against the sheets, says which document governs when an addendum settles it, and drafts an RFI when nothing does. Until the answer comes back, it tells you what it carried.

Questions only the architect or owner can answer become RFI drafts. You send them.

A crux chat: asked whether the door hardware on A-611 matches the spec, crux lists two conflicts, cited to section 08 71 00, Addendum 2 and sheet A-611, and has drafted RFI 07 to the architect. A crux chat: asked whether the door hardware on A-611 matches the spec, crux lists two conflicts, cited to section 08 71 00, Addendum 2 and sheet A-611, and has drafted RFI 07 to the architect.
Chat · door hardware, spec against drawingscrux app · sample job

02.3 Leveling

Sub quotes leveled, like for like.

crux reads each quote against the scope checklist in your scope letter. What a bidder left out gets a plug from another bidder's printed breakout, marked and cited, so the leveled totals compare the same scope. You pick the number to carry.

Each plug names its source: the quote, the page and the line.

A crux leveling sheet for drywall and ceilings: four bidders checked item by item against the scope, exclusions plugged from another bidder's printed breakout, and leveled totals with the carried bidder highlighted. A crux leveling sheet for drywall and ceilings: four bidders checked item by item against the scope, exclusions plugged from another bidder's printed breakout, and leveled totals with the carried bidder highlighted.
Leveling workbook · drywall and ceilingscrux app · sample job

02.4 Scope letters

Scope letters on your letterhead, every item cited.

One letter per trade package: a bid form the sub returns, the work included, alternates and breakouts priced separately, and what's by others, each item tied to its section or sheet, through the latest addendum.

Anything that leaves your company is a draft. You review it and you send it.

A crux scope letter draft for drywall and ceilings on the sample GC's letterhead: project details, the subcontractor bid due date, a synopsis, and the work included with its spec sections and sheets. A crux scope letter draft for drywall and ceilings on the sample GC's letterhead: project details, the subcontractor bid due date, a synopsis, and the work included with its spec sections and sheets.
Scope letter · drywall and ceilingscrux app · sample job

02.5 Takeoff

Quantities come from the geometry.

crux traces rooms, walls and openings from the drawing's vector lines, at the sheet's own scale, and computes the quantities you need: ceilings, flooring, doors, whatever the scope calls for. A picture can show where something is; it never sets a number. What crux proposes waits on the canvas for your approval.

When a dimension isn't on the drawings, crux asks you in chat and cites your answer.

The crux takeoff canvas on sheet A-101: rooms traced from the vector linework for ceilings, epoxy flooring and doors, condition totals in a Conditions panel at the top right, and a Needs your review bar with Approve 11 at the bottom. The crux takeoff canvas on sheet A-101: rooms traced from the vector linework for ceilings, epoxy flooring and doors, condition totals in a Conditions panel at the top right, and a Needs your review bar with Approve 11 at the bottom.
Takeoff canvas · A-101crux app · sample sheet

02.6 Estimate

Your template, filled in and checked.

crux carries the leveled sub numbers, your general conditions and the takeoff into your own estimate workbook, with the sub and a spec reference beside each line. A trade with no quote yet is budgeted from your company's history and marked, until a real number comes in.

Numbers you haven't confirmed stay labelled budget-grade, with where each one came from.

The crux estimate preview: the sample job's base bid workbook, one line per trade with the sub carried, the amount and a spec reference, and the budget lines marked. The crux estimate preview: the sample job's base bid workbook, one line per trade with the sub carried, the amount and a spec reference, and the budget lines marked.
Estimate preview · base bidcrux app · sample job

02.7 Calendar

Bid dates and job meetings, in one calendar.

crux reads your calendar and lists what's coming: bid dates, pre-bid walks, forms and bonds due, and the meetings on the jobs you've won. Each bid gets its folder in one click, and filters split bids, paperwork and meetings.

It reads your calendar. It never books or accepts anything for you.

The crux Calendar: upcoming bids with their owners, due times and days left, filters for bids, paperwork and meetings, and a Create bid folder action beside each bid. The crux Calendar: upcoming bids with their owners, due times and days left, filters for bids, paperwork and meetings, and a Create bid folder action beside each bid.
Calendar · bids and meetingscrux app · sample job

03 · BuildingConnected + Procore

BuildingConnected + Procore. crux sets up one and reads the other.

crux connects to the tools you already bid and build in, and does the setup for you. You check it, and you approve every change before crux makes it. Nothing goes out to a sub until you publish or press Send.

Each connector stays off until you turn it on in Settings. Each estimator signs in as themselves.

BuildingConnectedBidding

Your ITB, built and ready. You click Publish.

crux sets up the project, the bid packages and the invite lists in BuildingConnected. You look it over and click Publish in BuildingConnected.

  • Creates the project and its bid packages, or copies them from a past job, bidders included
  • Writes each package's scope form, line by line
  • Builds each invite list from your sub directory, skipping subs already invited
  • Shows each package's invites, views, commitments and bids in, and lists the subs to call
You publishInvites only on Send
ProcoreWon jobs

Your won job's Procore project, read from crux.

Link a won job to its Procore project and crux reads it for you: RFIs, submittals and drawings, each one cited back to Procore, for the precon, the submittal register and every question after.

  • Reads the project's RFIs, submittals and drawings, each with a citation
  • Coming: drawing uploads and sheet number and title fixes
  • Each change will show you exactly what it does first, and go only after you approve it
ReadsYou approve

04 · Brain

It gets smarter with every bid.

crux remembers what you teach it: your rates, your preferences, the calls you made and the lessons from every job. The next bid starts from all of it.

A local-first memory of facts, lessons and work sessions, linked as you work and kept on your own PC.

Memories
253
Facts
141
Sessions
61
Links
515
Fact 141 Lesson learned 21 Work session 61 Topic 5 Observation 25
253 memories

The live Brain view needs 3D graphics. Here is what this sample crux remembers.

Live demo · sample memories, made up for this pagecrux app · Brain

  • Remembers your numbers

    Labor and production rates, markups, and the exclusions you always carry. Tell it once in chat, or save it in Settings.

  • Learns from every job

    A lesson from one bid, like which drywall subs leave firestopping out of their number, is there for the next one.

  • You stay in charge

    See, search and correct what it knows. Say "forget the note about…" and it's gone.

  • Stays on your PC

    Memories live on your computer, not on our servers. Your memories are never shared with other crux users.

05 · Built-in knowledge

Construction knowledge, built in.

crux doesn't start from a blank page. It comes with an estimator's reference shelf: hundreds of pages of curated estimating guidance built from decades of industry knowledge, on practice, contract terms, prevailing wage and local rules. When crux leans on it, it tells you so. If something doesn't fit how you work, switch it off or correct it in your own words.

Hybrid retrieval, on your own machine: dense vector embeddings fused with BM25 keyword ranking, so a search finds what a passage means and the exact words it uses. Curated, versioned construction knowledge reaches the AI through crux's own MCP server, one section at a time, with your switch-offs and corrections applied before it reads a word. No answering from memory.

What it knowsBuilt in

A full reference shelf with every GC seat.

Hundreds of topics, each one a section crux can look up when a question needs it.

  • GC practice: markup build-up, general conditions, leveling, buyout, scopes of work and go/no-go
  • Public and federal work: the contract terms that move your number, explained in plain English, and prevailing wage
  • Curated estimating guides built from decades of industry knowledge
  • State and local rules, wage requirements and bonds
  • The painting pack adds its own shelf: coating systems, surface prep, spread rates, intumescents and lead rules
CuratedKept current
Yours to correctYou decide

Doesn't apply to you? Switch it off.

Every topic is listed in Settings with a one-line summary. You decide what crux uses.

  • Doesn't apply to us: turn a topic off and crux stops using it everywhere
  • Add a correction: write your version in your own words, and crux uses it over the built-in text
  • Your own rules and lessons go in the Brain and carry into every bid
Off means offYour words win

06 · Checked before you see it

No made-up numbers. No made-up answers.

AI can sound sure and still be wrong. crux's built-in checks stop AI hallucination before it reaches you, so what you read is what your documents say, and what crux doesn't know, it asks.

Guardrails on every answer: grounded in your documents, cited to the source, with a human in the loop for anything that leaves your company.

  1. C1

    Every claim cited

    Each fact points to the sheet, spec section or addendum it came from. Click the citation and the page opens, so you can check it in seconds.

  2. C2

    Unknowns become RFIs

    When the documents don't answer something, crux drafts an RFI to the architect or owner, or asks you in chat. It never fills the gap with a guess.

  3. C3

    Quantities from geometry

    Lengths, areas and counts are measured from the drawing's vector lines at the sheet's scale. AI finds things on the sheet; it never sets a number.

  4. C4

    Costs flagged by origin

    Prices you haven't confirmed are marked budget-grade, with where each one came from, until you confirm them.

  5. C5

    Drafts only. You send.

    RFIs, scope letters, invites and emails are drafts. You review and send everything that leaves your company; crux never sends on your behalf.

07 · Add-on packs

Add-on packs. Painting first.

crux is built for the GC's side of the bid, and every GC seat comes with the GC pack. A trade pack adds one trade's own knowledge: the spec sections it cares about, its takeoff rules, production rates, labor and material defaults, and its proposal language. Add one for the work you self-perform, or run crux as a specialty sub on a subcontractor seat.

First add-on packAvailable at launch

Painting and coatings

For painting you self-perform, or for commercial painting subcontractors.

  • Painting, staining and transparent finishes, high-performance and special coatings
  • Wall coverings, fluid-applied flooring and intumescent coatings
  • Lead-based paint rules and red flags
  • Default production rates and proposal language you can replace with your own
09 9109 9309 9609 9709 7209 67
More packs

More trades are coming

The core is built trade-agnostic, so each new trade is a new pack, not a new product. Your seat stays the same. Tell us which trades you self-perform or bid.

Tell us your trade

08 · On your phone

crux on your phone. Take the job with you.

On the walk, in a meeting, out on the jobsite: keep working the job from your phone. Ask crux and get a cited answer, see where every chat stands, and lean on what crux knows. Your PC does the work back at the office.

Your bids stay on your PC. Your phone shows your chats.

crux on a PC with the Use crux on your phone window open: a pairing code to scan with the phone's camera, a two-minute countdown, and the line Works once. Your bids stay on this PC. crux on a PC with the Use crux on your phone window open: a pairing code to scan with the phone's camera, a two-minute countdown, and the line Works once. Your bids stay on this PC.
crux on a phone: a chat on the sample GC job asks who furnishes the science wing's fume hoods; crux answers with two spec citations and a crux knowledge tip. crux on a phone: a chat on the sample GC job asks who furnishes the science wing's fume hoods; crux answers with two spec citations and a crux knowledge tip.
The cited spec page open on the phone, Section 11 53 13 paragraph 1.4.A boxed, with arrows to page through the project manual. The cited spec page open on the phone, Section 11 53 13 paragraph 1.4.A boxed, with arrows to page through the project manual.
Pair on the PC, then chat and check the page on your phonecrux app · sample job
  • Paired in seconds

    Click the phone icon in crux and scan the code with your phone's camera. Match one symbol on both screens and you're in.

  • Any job's chat, or a new one

    Pick up any chat where you left it, or start a new one in any job. See which chats crux is working on and which need you.

  • Tap a citation, see the page

    Answers keep their citations. Tap one and the page opens on your phone with the cited words boxed, and you can page through the document.

  • Approve from anywhere

    When crux asks before it does something, answer from your phone with the same choices you get on the PC.

  • End-to-end encrypted.
  • Keys are made on your PC and your phone, and never leave them.
  • Each pairing link works once, on one phone.
  • Disconnect from your PC or your phone, any time.

09 · Pricing

One seat per estimator. Pick your side of the bid.

A seat is one licensed user on one Windows computer, with the full app, updates and support. A subcontractor seat comes with the trade pack for your trade; a GC seat with the GC pack. crux isn't on public sale yet: request early access and we'll send your checkout link when your seat is ready.

Subcontractor seat

Specialty subs
$3,990per seat / year

billed once a year; renews yearly until you cancel

  • One trade pack of your choice included
  • Extra trade packs $990/yr each

Your trade pack: the spec sections your trade cares about, its takeoff rules, production rates, labor and material defaults, and the proposal language that protects you. Painting and coatings is the first; more trades are coming.

Request early access

Billing terms

  • Yearly subscription, billed once a year in advance, in US dollars, through Stripe. New and renewing subscriptions are yearly; monthly plans are no longer sold.
  • Renews automatically every year until you cancel, at $3,990 per subcontractor seat or $6,990 per GC seat. Stripe emails you a reminder 30 days before each renewal.
  • Cancel anytime from the billing portal. Cancellation takes effect at the end of the year you've paid for; you keep access until then.
  • No refunds, except your first payment if you ask within 7 days, and the unused part of your prepaid year if we shut crux down or end your subscription for a reason that is not your fault. Renewals are not refunded. See our Refund & Cancellation Policy.
  • Prices are plus any applicable sales tax.
  • One seat, one computer. Move a seat by deactivating it in the app, or ask us to reset it.
  • Trade packs. A subcontractor seat includes one trade pack; a GC seat includes the GC pack and one sub trade pack. Each extra trade pack is $990/yr.

Every seat includes

  • The crux desktop app for Windows, with automatic updates.
  • One trade pack of your choice (a GC seat: the GC pack and one sub trade pack): its skills, takeoff rules, production rates and templates. See which packs are available.
  • Labor rate sets for open shop, union, prevailing wage and Davis-Bacon, plus default production rates you can replace with your own.
  • Default estimate and proposal templates, or use your own.
  • Email support at support@cruxai.bid.

You'll also need a Windows 10 or 11 PC (see system requirements) and your own paid Claude subscription from Anthropic, billed separately by Anthropic. crux does not include or resell Claude.

10 · Why Claude

Why Claude?

We tested 10 AI models on a real public-school bid set. Claude Opus was the most accurate.

  • 99.5out of 100, #1 overall
  • 0made-up sources
  • 1 of 10models caught the hidden conflict, both times
Overall scoreout of 100, average of both tests
  1. Claude Opus 5.599.5
  2. Grok 4.795.5
  3. GPT-6.1 Sol94.6
  4. Gemini 4 Argon93.6
  5. Mistral Large 484.7
  6. Kimi K3.1 Pro84.5
  7. DeepSeek V4 Pro81.7
  8. MiniMax M380.3
  9. Llama 4 Maverick37.1
  10. gpt-oss-120b30.4
How we tested

Two tests. First, we handed each model the pages it needed. Then each model had to search the full 1,229-page project manual, addendum and drawings itself and cite what it found, the way crux works. Overall is the average of the two.

The rules. Same questions for every model, each run twice. A script scored them; no AI graded another. Requests went only to providers that don't keep the data.

ModelHanded the pagesPagesSearching the manualSearchOverall
Claude Opus 5.599.899.299.5
Grok 4.791.999.295.5
GPT-6.1 Sol91.797.594.6
Gemini 4 Argon93.294.093.6
Mistral Large 494.575.084.7
Kimi K3.1 Pro84.884.284.5
DeepSeek V4 Pro75.088.381.7
MiniMax M379.780.980.3
Llama 4 Maverick63.111.137.1
gpt-oss-120b60.80.030.4

11 · Your data

Your numbers are yours.

crux runs on your computer, not ours. The memory, the checks and the knowledge base around the AI all live on your machine. Your bids, drawings, rates and pricing never touch crux's servers; we couldn't see them if we wanted to.

crux's servers

Licensing and billing. Nothing else.

  • Your email address
  • Your license key
  • A device key for your one computer
  • License and usage events

Stripe handles payment, so card numbers never reach crux. Emails go out through Resend.

Your computer

Everything you work on stays here, in your own folders.

  • Bid documents, drawings and addenda
  • Takeoffs, estimates and proposals
  • Rates, pricing and company knowledge
  • Chats, RFIs and drafts

Backups and company profiles are files you save where you choose, locked with your own password. crux can't open them.

Your Claude account

The AI runs on your subscription, under your login.

  • Your own Claude plan
  • Your own sign-in
  • Your own agreement with Anthropic

When crux reads a document for you, it goes to Anthropic under that agreement, never through crux.

For your IT team

What's under the hood, in your terms.

The short version for whoever looks after your computers and your network.

  • A purpose-built harness, not a chatbot. crux wraps Claude in 175+ construction-specific tools, safety guards and skills, served by custom MCP servers: how to read a spec book, measure, cite every claim, check addenda and stop before guessing.
  • Local vector search. Each project's documents are indexed for search on the user's own Windows PC. Project files stay on your computers and your network.
  • Your company's own Claude subscription. The AI runs under your own Claude sign-in. Our servers handle licensing and billing only and never hold your documents.
  • Guardrails and human-in-the-loop. Every claim is cited to its source, unknowns become questions, and everything that leaves your company is a draft a person sends.
  • Encrypted, licensed trade packs. Packs download through the app for the seats you license. One seat per device.
  • Self-healing services. crux restarts its own background services if one stops. No ports, servers or databases for IT to run.
  • Windows 10 (22H2) or 11, 64-bit. Installs for one Windows user, with no administrator rights for crux itself.

Read the privacy policy

12 · FAQ

Questions estimators ask.

Can I buy crux today?

Not yet. crux is in private beta and is not on public sale. Request early access and we'll email you when a seat is ready, with a secure Stripe checkout link. You won't be charged anything until you complete that checkout.

Can crux see my bids, drawings or pricing?

No. crux runs on your computer. Your bid documents, drawings, takeoffs, estimates, rates, pricing, proposals, chats and company knowledge stay in your own folders and never touch crux's servers. Backups and company profiles are files you save where you choose, locked with a password you choose; crux can't open them.

The AI works through your own Claude account. When crux reads a document for you, that content goes to Anthropic under your own agreement with Anthropic, not through crux.

crux's servers handle licensing and billing only: your email, your license key, a device key for your one computer, and license and usage events. Stripe handles payment, so card numbers never reach crux. See the Privacy Policy.

What kind of work is crux made for?

Commercial construction, from the general contractor's side first. crux is made for the way commercial jobs are bid and built: project manuals and spec sections, drawing sets, addenda, trade packages and scope letters, sub quotes, prevailing wage and Davis-Bacon labor, submittals and subcontracts.

How much faster is it?

Reading a commercial bid set, sorting it and reconciling the addenda typically takes an estimator four to five hours. crux reads most bid sets in 10 to 30 minutes (a real 1,781-page set took about 33) and writes them up, cited, in your binder while you keep working. Because it runs bids side by side, you can work several projects at once.

Which trades does crux support?

crux is built for general contractors, and every GC seat comes with the GC pack. Trade packs are add-ons: one for each trade you self-perform, or the pack for your trade if you're a specialty sub. The core (reading the bid set, measuring, citing, drafting) is the same for everyone; a trade pack adds that trade's skills: its spec sections, takeoff rules, production rates and proposal language.

Painting and coatings is the first trade pack, with lead-based paint rules built in. Others are coming. Tell us your trade when you request early access and we'll let you know when its pack is ready.

What does a seat include? What does another trade pack cost?

crux is billed once a year. A subcontractor seat is $3,990/yr and includes one trade pack of your choice. A GC seat is $6,990/yr and includes the GC pack and one sub trade pack. Each extra trade pack is $990/yr, for subs and GCs alike.

What does the GC seat include?

The GC pack, with bid leveling, scope letters, a company cost and competitor database with the Intelligence tab, the GC estimate workbook, bid day and buyout, optional BuildingConnected and Procore connections, shared-drive teamwork and conformed sets. It also includes one sub trade pack, for the work you self-perform; further sub packs are $990/yr each.

Do I need a Claude subscription?

Yes. crux runs on your own paid Claude subscription from Anthropic, which you buy and manage separately. During setup, crux installs Anthropic's official Claude app and you sign in with your own account. crux doesn't include, resell or pay for Claude usage.

How does it get quantities? Does it guess?

It never guesses. Quantities are computed from the vector geometry in your PDF drawings: lengths, areas and counts. Images are used only to find what and where. When something needed for a quantity isn't in the documents, such as a wall height, crux asks you and records your answer as the source.

Scanned, image-only drawings don't carry vector geometry, so crux will tell you what it can't measure rather than estimate it.

Does it work on a Mac?

Not at launch. crux is a Windows desktop app for Windows 10 and 11 (64-bit).

What computer do I need?
crux system requirements
MinimumRecommended
WindowsWindows 10 (22H2) or 11, 64-bitWindows 11, 64-bit
Processor4 cores (Intel Core i5 or AMD Ryzen 5, 2019 or newer)8 or more cores (Core i7/i9 or Ryzen 7/9)
Memory16 GB32 GB or more
StorageSSD with 10 GB freeSSD with 25 GB or more free
Screen1920 × 10801920 × 1080 or larger; a second monitor helps for takeoff
GraphicsBuilt-in graphicsAny modern graphics card (optional speed-up)
InternetBroadband, while you use cruxWired or strong Wi-Fi
SoftwareLibreOffice (free, required; crux installs it during setup)Also Microsoft Excel and Word, to open your files outside crux
ClaudeClaude Pro subscriptionClaude Max, for heavy bid weeks

crux itself needs no administrator rights: it installs for your Windows user only. LibreOffice, which crux needs to show your estimate and proposal inside the app, comes from its publisher during setup, and its installer may ask Windows for permission once. The heaviest moment is when crux first reads a bid set: a 900-page set takes about 15 minutes on a recommended PC and longer on a minimum one. Chat, estimates and proposals are light, because the AI itself runs on Anthropic's servers.

What is a seat? Can I move it to a new computer?

A seat is one license for one person on one computer. To move to a new computer, deactivate the seat in the app on the old one and activate it on the new one. If the old computer is lost or dead, email us and we'll reset it.

How do I cancel?

Cancel anytime from the Stripe billing portal (linked from the app and from your receipts). Cancellation takes effect at the end of the year you've paid for, and you keep full access until then. Stripe emails you a reminder 30 days before each yearly renewal. There are no refunds, except your first payment if you ask within 7 days and the unused part of your prepaid year if we shut crux down or end your subscription for a reason that is not your fault; renewals are not refunded. See the Refund & Cancellation Policy for details.

Will it send emails or bids for me?

No. RFIs, scope letters, proposals and emails are drafts, and BuildingConnected invites go out only when you press Send. crux sets up your bid packages in BuildingConnected; you publish them. You review everything and you send it. In Procore, crux only reads today; when it starts making changes there, each one will wait for your approval too.

13 · Early access

Bid your next job with crux.

We're opening seats to a small group of companies first, starting with general contractors (the GC pack) and painting and coatings, the first trade pack. Tell us who you are and what you bid, and we'll be in touch.

Or email us directly support@cruxai.bid

This opens an email to support@cruxai.bid in your own mail app. Nothing is sent until you press send, and this website doesn't store what you type.