LangChain vs LlamaIndex
LangChain agent framework versus LlamaIndex retrieval-focused stack: abstractions, ecosystem, RAG performance, and which fits your AI app architecture.
Refresh the data, not the model: an architecture that adds the relevant chunk to the context on every query
Embed all the data directly into the prompt, no retrieval needed + prompt caching
It depends — but the breakeven point is lower than you'd think. With sourced pricing, the breakeven is ~200K tokens (at a 5K chunk size): below that, cache-backed long context is both simpler and cheaper; above it, the per-query cost tips in RAG's favor. For frequently updated, massive, or per-user-authorization-gated data, RAG's access-control and freshness advantages can't be substituted. In mature architectures, the common pattern is using both together on different data slices.
| Category | RAG (Retrieval-Augmented Generation) | Uzun bağlam (1M+ token) |
|---|---|---|
| Performance | 7/10 | 7/10 |
| Ease of Learning | 5/10 | 9/10 |
| Ecosystem | 9/10 | 7/10 |
| Community | 9/10 | 7/10 |
| Job Market | 8/10 | 6/10 |
| Future-Proof | 8/10 | 9/10 |
# OpenAI Responses API — File Search (a managed RAG tool)
# As of September 2026, official docs: platform.openai.com/docs/guides/tools-file-search
from openai import OpenAI
client = OpenAI()
response = client.responses.create(
model="gpt-6-astra",
input="Q3 finansal raporunda net kâr marjı neydi?",
tools=[{
"type": "file_search",
"vector_store_ids": ["vs_abc123"],
}],
)
print(response.output_text)
# This hosted tool manages embedding + indexing + retrieval on OpenAI's side
# (works with no code). Cost: $2.50 per 1k tool calls
# + storage $0.10/GB/day (first 1GB free). Source: platform.openai.com/docs/pricing# Claude API — making a 1M-token context cheaper with prompt caching
# Source: platform.claude.com/docs/en/build-with-claude/prompt-caching
import anthropic
client = anthropic.Anthropic()
response = client.messages.create(
model="claude-sonnet-5",
max_tokens=1024,
system=[
{
"type": "text",
"text": full_knowledge_base_text, # e.g. 800K tokens of internal documentation
"cache_control": {"type": "ephemeral"},
}
],
messages=[{"role": "user", "content": "Onboarding sürecinde hangi adımlar zorunlu?"}],
)
# First call: billed at the full input price (cache write).
# Subsequent calls (within a short window, e.g. 5 min): the cache-read price applies
# — a small fraction of the base input price (see the official pricing page).It depends — but the breakeven point is lower than you'd think. With sourced pricing, the breakeven is ~200K tokens (at a 5K chunk size): below that, cache-backed long context is both simpler and cheaper; above it, the per-query cost tips in RAG's favor. For frequently updated, massive, or per-user-authorization-gated data, RAG's access-control and freshness advantages can't be substituted. In mature architectures, the common pattern is using both together on different data slices.
Get Free ConsultationYes, but not in every scenario anymore. 1M+ context windows have greatly reduced the need for RAG on static, single-session queries. Retrieval is still necessary in three cases: frequently updated data (the cache goes stale on every update), multi-tenant data that needs per-user/row-level access control, and corpora that exceed the per-request context ceiling (1M tokens).