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The Bid Engine is NEXOS CORE’s construction, low-voltage, and electrical bidding tool — it replaces an Excel cost workbook with a server-side calculation engine and AI-assisted takeoff. Create a bid sheet, upload the spec documents and drawings, and NEXOS CORE reads the drawings with Claude Vision to count devices, generates line items grouped by trade, applies addendums, writes a scope narrative, and runs a pre-submission audit — all while computing hard cost, margins, tax, commission, and grand total deterministically. Open it at /bids.

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When to use it

  • Bid a construction / low-voltage / electrical job (cameras, cabling, access control, fire alarm).
  • Take off devices from plan sets without hand-counting.
  • Re-scope existing line items against issued addendums.
  • Get a pre-submission sanity check before you send a bid.
  • Generate a contractor-readable scope-of-work narrative from the source docs.

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Cost math

Costing is deterministic: material + tax + subs + equipment + labor + burden = hard cost; hard cost × (overhead + profit + contingency); + commission; + customer sales tax; + permits and bond = grand total — with profit per man-day, margin %, and an optional manual bid-price override.

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Drawing takeoff (Vision)

Point the engine at a bid’s drawings and it runs Claude Vision (via the Drawings module) to count low-voltage devices, then generates trade-grouped line items from the takeoff — drawings are authoritative for quantities. Takeoff is scoped to the trades the bid actually covers.
The same device can appear on several sheets (floor plan, RCP, riser). The Vision Findings audit surfaces per-sheet counts and duplicate tags, and Dedupe by tag keeps the highest-quantity sheet — review it, since it’s a heuristic that can drop a legitimate sheet.

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Addendums

Upload an addendum and each page is mirrored in; a sheet whose number matches a base drawing automatically supersedes the older one. For line-item impact, AI produces a reviewable diff (partial-scope aware — e.g. “terminations by others” trims labor rather than deleting the cable), which you Apply or Dismiss per change.

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Reconciliation, scope summary, and audit

  • Reconcile compares spec-required vs. drawing-observed quantities, row by row.
  • Scope summary generates an editable SoW narrative (overview, in/out scope, assumptions, risks, quantities).
  • Pre-submission audit flags red/yellow/green findings (phantom OFCI hardware, double-counted labor); red findings block moving a draft to submitted.

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Good to know

  • The AI steps (takeoff, reconcile, addendum diff, scope summary) require your tenant’s Claude API key and carry a per-drawing cost.
  • Confidence scores on generated items are AI-supplied estimates — verify before you submit.