Platform · Developer SDK

Future · in design

Motion intelligence, as an API.

Everything Vahini builds runs on one engine: score a scanned page across 20 factors, or read the pen's 16-axis motion directly. The Developer SDK opens that engine to partners, so banks, edtech and healthtech can build on it without touching the hardware or the data pipeline.

Become a design partner Try the engine live
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The idea

One engine, two doors in.

The 20-factor scan engine already scores real pages inside the live analyser. The pen adds what no scan can see: pressure, tilt, speed and pen-lifts at 208 Hz. The SDK exposes both through one versioned API at api.vahinitech.com, with the same scoring engine behind every call, so a partner's integration works today with scans and gets deeper the day their users pick up the pen.

What we expose

Three API families, opened in order.

01

Scan API · first to open

POST one scanned or photographed page, get the 20-factor scorecard, handwriting OCR and plain-language insights as JSON. These are the same endpoints that power the live analyser today.

02

Pen Motion API · with the pen

Register pens, open write sessions, stream batched 16-axis IMU frames at 208 Hz, and read back reconstructed strokes and the writer's 20-factor Writing DNA.

03

Webhooks & exports

Report-ready events for your app, white-label PDF reports, and consent-scoped dataset exports for research partners under DPDP.

Endpoint preview

The surface we are building towards.

POST/v1/scan/reportOne page image in, the full 20-factor scorecard with coaching exercises out.Engine live
POST/v1/scan/ocrIndic handwriting OCR: English and Telugu today, more scripts as the dataset grows.Engine live
POST/v1/scan/insightsVision-language insights: reading confidence, legibility and quality signals for a page.Engine live
POST/v1/pens/{pen_id}/sessionsOpen a write session for a registered pen and a consented writer.In dev
POST/v1/sessions/{id}/framesBatched 16-axis motion frames from the pen's BLE gateway, 208 Hz.In dev
GET/v1/sessions/{id}/strokesThe reconstructed pen-tip path, cleaned by the on-pen Kalman filter.In dev
GET/v1/writers/{id}/dnaThe writer's 20-factor Writing DNA profile and its change over time.Planned
POST/v1/signatures/verifyVerify how a signature was written, motion against motion, not shape against shape.Planned
# score one scanned page, today's engine behind tomorrow's key
curl -X POST https://api.vahinitech.com/v1/scan/report \
  -H "Authorization: Bearer vah_live_…" \
  -F page=@worksheet.jpg

# → 200 OK
{ "factors": { "pressure": 72, "slant": 64, "spacing": 88, … },
  "summary": "Strong formation; spacing needs work.",
  "exercises": [ … ], "report_url": "https://…/report.pdf" }

How access will work. Versioned REST under api.vahinitech.com, API keys per partner, per-call metering, sandbox keys for development, and DPDP consent scopes on anything that touches a writer's data. The scan engine is live inside our own products today; the public key programme opens with design partners first.

Monetisation

Metered API, SaaS seats, enterprise licences.

The same engine sells three ways. Partners meter by the call, schools subscribe by the seat with reports as the deliverable, and enterprises license pilots and the motion dataset itself. Every call is metered against a key from day one, which is what turns the API into a SaaS business rather than a free integration.

Developers & partners

Pay per call

₹0.50 / API call, volume tiers

Metered access to the scan and motion endpoints with sandbox keys free during development.

  • API keys & usage dashboard
  • Volume pricing as calls grow
  • Sandbox free while you build
Schools & institutions

Coaching SaaS

₹999 / seat / year

The full coaching product on top of the API: scorecards, exercises and progress reports per student.

  • White-label reports for partners
  • Teacher & cohort dashboards
  • State-language packs as they ship
Enterprise & research

Pilots & licensing

₹5–25L / pilot · annual licences

Signature verification for banks, screening programmes for health, and consent-scoped dataset licences for AI labs.

  • Custom endpoints & SLAs
  • On-prem or private-cloud options
  • Dataset licensing under DPDP

Roadmap

Opening in the order the engine matured.

Now

Engine in production

The scan endpoints already score real pages inside the live analyser. We are recruiting design partners to shape the public surface.

Next

Keys, metering, docs

Partner API keys, per-call metering and billing, a sandbox, and public documentation for the Scan API.

Then

The pen goes live

Motion sessions and stroke streams ship with the pen, followed by Writing DNA profiles and signature verification.

Want to build on the motion layer?

Tell us what you would build and we will shape the first API keys around real partners, not guesses.

Become a design partner The business case, in the notebook