The answer cited a policy. The policy had expired six months earlier.
The assistant found a relevant paragraph, but the index contained two versions. It chose the older one, wrote a confident answer, and displayed a citation that made the mistake look trustworthy.
RAG is not accurate because it has a vector database. It becomes dependable when source versions, permissions, retrieval tests, citations, and refusal behaviour are designed as one system.
First scope
- 1 to 2
- knowledge sources in a focused first release
- Keep the evaluation boundary clear
- 4 to 8 weeks
- typical focused delivery window
- Depends on source and access complexity
- $15K
- starting development price
- Fixed after source and question review
RAG earns its cost when answers must use private knowledge and show their evidence.
A plain model call is simpler when the necessary context is small, stable, and already supplied in the request.
A fit01Employees or customers repeatedly ask questions answered by approved documents, tickets, or records.
02Knowledge changes often enough that citations, versions, and deletion behaviour matter.
03Different users have different permission boundaries over the same source collection.
Not a fit01The task is mainly tone, style, or output-format control rather than knowledge retrieval.
02The answer depends on judgment that no approved source contains.
03The source material is contradictory and nobody can decide which version governs.
Scope
What a production RAG system needs
01Ingestion with source identity
Parsers preserve document, section, date, version, link, and access metadata.
Update and deletion paths keep the index aligned with the approved source
instead of creating an unmanaged copy.
02Retrieval tuned on real questions
Dense and keyword search, metadata filters, and reranking are chosen from the
corpus and query set. Retrieval is evaluated before answer fluency can hide a
missing passage.
03Permission-aware context
User identity and source permissions constrain results before text reaches the
model. Tests cover allowed, denied, mixed-access, and revoked-document cases.
04Citations, refusal, and monitoring
Answers link to the supporting passage and version. When the evidence is weak
or absent, the interface says so and offers the next useful step. Logs
separate source, retrieval, generation, and cost failures.
RAG vs fine-tuning
| RAG | Fine-tuning |
|---|
| Best fit | Private or changing knowledge with source evidence | Repeatable behaviour, style, format, or a narrow task |
| Knowledge update | Re-index the changed or deleted source | Prepare data, retrain, and evaluate another model version |
| Citation | Can link the answer to retrieved passages | Does not expose which training example supports a claim |
| Main failure | Wrong, missing, stale, or unauthorized retrieval | Insufficient examples or behaviour that fails to generalize |
| First test | Can search find the right evidence? | Does training improve the task beyond prompting? |
For broader model integration controls, see LLM integration services. AI knowledge management owns the employee-facing workflow, while AI semantic search owns search experiences that may not generate an answer.
How it works
From source inventory to evaluated answers
A labelled question set keeps retrieval and generation honest.
- Phase 1
01Define questions and evidence
Choose one workflow, approved sources, user groups, and a labelled set of
questions with expected passages, unacceptable answers, and permission cases.
- Phase 2
02Prove ingestion and retrieval
Test parsing, chunking, metadata, versions, permissions, hybrid search, and
reranking on representative content. Fix missing evidence before adding
generation.
- Phase 3
03Add answers and refusal paths
Generate from the retrieved context, display source links, validate access,
and decline or escalate when evidence is insufficient.
- Phase 4
04Release and monitor quality
Measure retrieval misses, unsupported statements, stale sources, latency,
cost, and user escalations before expanding the corpus or audience.
- A fluent answer hides weak retrieval
- Score whether search found the expected evidence before judging the prose. The model cannot repair a missing source passage reliably.
- Permissions are filtered after generation
- Unauthorized content has already crossed the boundary once it reaches the model. Filter during retrieval and test revoked access.
- Old versions remain searchable
- Every connector needs update, supersession, and deletion behaviour. A citation to an expired policy is still a wrong answer.
- A universal accuracy number replaces evaluation
- Quality depends on the buyer's corpus, questions, and acceptance rules. We do not promise a benchmark percentage before testing those inputs.
Scope and price
A focused RAG system starts at $15,000.
Begin with one use case, one or two sources, a labelled question set, retrieval, citations, access controls, and a handover path.
Multi-domain systems grow in fixed phases after the first corpus clears its agreed retrieval and answer thresholds.
Starting investment
Starts at $15,000
A focused first release usually takes 4 to 8 weeks. Source quality, custom connectors, and permission complexity move the estimate most.
Retrieval measured separately
The evaluation shows whether the right evidence was found before generation
quality is judged. That makes failures diagnosable.
Fixed-price phase
Once the sources, questions, permissions, acceptance rules, and handover are
agreed, the phase price is locked in writing.