REFERENCE IMPLEMENTATION

An answer engine, assembled from Harper primitives.

A working reference implementation of a grounded answer system, built entirely on Harper. Hybrid retrieval, semantic caching, and embed generation run together in one runtime.
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Speak to a Harper partner for more details.

Grounded Answers

Responses are built from the business knowledge you trust, not from an LLM's general recall.

Less Inference

Validated answers are reused when it is safe, so the model never solves the same question twice.

Built on Harper

Every part of this runs on Harper primitives. There is nothing proprietary to adopt.
WHAT IT SHOWS

Al answers, inside the search box you already have.

This implementation shows how a grounded answer layer can sit behind an existing search experience. Requests come in over Harper's REST interface, and grounded answers go back to the interface you already own. There is no new product for your users to learn.
WHY THIS PATTERN

More useful AI, without more AI infrastructure.

Not every question needs a fresh trip through the whole AI pipeline. This build shows how an application on Harper can find the right business context, generate a grounded answer, and reuse that answer when it is safe to do so.
QUALITY

Give users better answers.

Ground responses in the content and operational knowledge your business trusts, instead of leaving the model to answer from general knowledge.
ECONOMICS

Send less work to the model.

Repeated and semantically similar questions reuse validated answers when serving rules allow it, which cuts unnecessary inference.
ARCHITECTURE

Improve what you have.

This Harper application pattern, can sit behind existing search, support, app, and agent experiences.
ECONOMICS AT SCALE

More questions should not mean proportionally more inference.

As usage grows, the answer layer can reuse validated answers for semantically similar requests instead of sending every request back through the model. That changes the unit economics of high volume search, support, and AI workloads.
Example workload 45 days
Where the questions went 73% answered without a new model call
Answer reuse Sent to model
QUESTIONS ASKED
123,411
Illustrative workload
MODEL CALLS AVOIDED
89,966
Less repeated model work
RESULT
Lower cost
As repeated intents accumulate
Illustrative workload shown to explain Answer Engine behavior. Actual reuse rates and savings depend on workload, model pricing, cache eligibility, and configuration.
HOW IT FITS

Keep the experience.
Add the answer layer.

Your interface sends Harper a question, and Harper already holds every piece needed to answer it: knowledge and data in its tables, keyword and vector search, an answer cache, routing, grounding, and generation. No separate vector database, cache, or serving layer to wire up. A grounded answer returns to the interface you already own.

Built In Capabilities

RETRIEVAL

Hybrid Retrieval

Combine keyword and vector search to find the most relevant evidence for each question, then rank the results into usable context.
LEXICAL + VECTOR + RERANKING
TRUST

Citation Grounding

Generate from retrieved evidence and return supporting sources with the answer, giving users and teams a clear path back to the underlying information.
GROUNDED ANSWERS + SOURCE TRACEABILITY
EFFICIENCY

Safe Semantic Cache

Reuse validated answers when serving rules allow it, avoiding unnecessary model calls while keeping live or entity-specific questions on a fresh path.
FEWER MODEL CALLS + FASTER REPEAT ANSWERS
CONTEXT

Live Business Context

Bring documents, web content, and operational data into the same answer path when the request depends on current business state.
KNOWLEDGE + CURRENT OPERATIONAL DATA
ORCHESTRATION

Model Escalation

Route requests through the lightest path that can answer them, escalating to model inference only when generation or deeper reasoning is needed.
USE INFERENCE WHEN IT ADDS VALUE
PERFORMANCE

On-node Generation

Keep retrieval, application logic, state, and generation close together on Harper, reducing the network hops and coordination required by a stitched stack.
LESS PLUMBING + LOWER OVERHEAD
BUILD IT

Three inputs.
Then run it on Harper.

The retrieval and serving pipeline is not a system you assemble before the first question can be answered.
01

Connect your knowledge.

Point it at the website, documents, knowledge content, or Harper-hosted data behind the experience.
02

Choose the model.

Keep model choice separate from the experience. Harper handles the context and answer workflow around it.
03

Connect your experience.

Send requests through the serving interface that fits your app or agent, and return the result where users already expect it.
THE ARCHITECTURAL DIFFERENCE

The alternative is assembling another AI stack.

A production answer system usually means connecting and operating a collection of specialized components. Harper collapses that answer path into one runtime, and this implementation shows it.
ASSEMBLE IT YOURSELF

More systems between the question and answer.

Your Knowledge
Your Model
Your Application
+
Content Ingestion
Chunking
Embeddings
Vector Database
Lexical search
Reranking
Caching
Model orchestration
Serving API
Observability
Each component can be excellent on its own. Your team still owns the integration, data movement, scaling, and operational boundaries between them.
ON HARPER

One answer layer behind the experience.

Your Knowledge
Your Model
Your Application
+
Harper
Retrieval, grounding, answer reuse, orchestration, serving, and operational visibility live together in Harper, instead of becoming another integration project.
THE INTERFACES

One answer layer. Multiple ways to ask.

Ask for a complete grounded answer, retrieve ranked context, or expose the same capabilities to an agent. These are the endpoints the implementation exposes on Harper. Clone it and call them yourself.
REQUEST
POST /answer HTTP/1.1
Host: answers.example.com
Content-Type: application/json

{
  "query": "Can I return swimwear without a receipt?"
}
WHAT COMES BACK
{
  "answer": "Yes. Swimwear can be returned within 30 days of purchase as long as it is unworn and the hygiene liner is intact. Without a receipt, store credit can be issued at the current selling price with a valid ID.",

  "sources": [
    {
      "title": "Returns & Exchanges",
      "url": "https://shop.example.com/help/returns"
    },
    {
      "title": "Swimwear Return Policy",
      "url": "https://shop.example.com/help/swimwear"
    }
  ]
}
GROUNDED
2 sources
CACHE
HIT
MODEL CALL
SKIPPED
LATENCY
3 ms

Deliver grounded answers from Harper.

Connect the knowledge your business trusts, the model you prefer, and the experience your customers already use. Then run it on Harper.
Learn More About Harper
Looking for a managed version?
Speak to a Harper partner for more details.