RAG (Retrieval Augmented Generation)
RAGTechnique that connects a language model (LLM) to a company's own knowledge base through vector search. The LLM retrieves relevant documents before generating its answer, reducing hallucinations and enabling citations of company-specific sources.
Example:A RAG support chatbot connected to a dental clinic's internal manual: when a patient asks 'how long does an implant take to heal', the system retrieves paragraphs from the official protocol and generates the answer citing them.
💡 SprintMarkt implements RAG chatbots from €1,125 with a Claude/GPT + pgvector + PostgreSQL stack.
How we apply it →Process of continuing the training of a base LLM with specific data to specialize it in a domain. Unlike RAG (which adds context at inference time), fine-tuning modifies the model's weights.
Example:Fine-tuning a base model with 5,000 question-answer pairs from the Spanish legal sector, so it answers with correct legal terminology without needing context supplied every time.
💡 SprintMarkt recommends RAG over fine-tuning in 90% of SMB cases: cheaper, more flexible, updatable without re-training.
How we apply it →Database specialized in storing and searching numeric vectors (embeddings) with semantic similarity search. 2026 alternatives: pgvector (PostgreSQL), Pinecone, Weaviate, Qdrant, Chroma, Milvus.
Example:pgvector lets you store the embeddings of a client's 500 PDFs and, given a question, find the 5 most relevant fragments in milliseconds.
💡 SprintMarkt uses pgvector by default in RAG implementations — zero additional cost if the client already runs PostgreSQL.
Tool Use (Function Calling)
Ability of an LLM to invoke external functions (APIs, databases, code) during its reasoning. The foundation of 'AI agents'.
Example:An AI agent with tool use can: receive 'how many sales did I close yesterday?' → call the CRM API → process the response → return '42 sales worth €18,500'.
Autonomous LLM-based system that receives goals in natural language, plans steps, uses external tools and executes tasks to completion. More complex than a chatbot.
Example:A 'sales assistant' agent receives 'prepare my meeting with client X', queries the CRM, summarizes recent interactions, looks up recent company news and generates a PDF briefing.
💡 SprintMarkt AI automations from €3,750 and custom AI agents from €13,500 (multi-tool with RAG).
How we apply it →MCP (Model Context Protocol)
MCPOpen protocol proposed by Anthropic in 2024 to connect LLMs to data sources and external tools in a standard way. Ecosystem of 'MCP servers' for GitHub, Notion, Slack, etc.
Example:A team can connect Claude to its Notion via the official MCP server, letting the LLM read, search and create pages without custom code.
Feature that forces an LLM to return JSON or another structured format according to a schema. Eliminates post-processing with fragile regexes.
Example:Asking GPT-5: 'extract name, email and company from the following email' with structured output returns validated JSON, not free text.
Protection layers applied to LLMs to prevent dangerous, off-topic or policy-violating outputs. Include: input filtering, output validation, prompt injection detection.
Example:Guardrails for a banking chatbot: blocks investment-advice questions (not authorized), detects prompt injection attempts, validates that answers do not mention competitors.
Critical comparison. RAG is better when information changes frequently, the dataset is large or sources must be cited. Fine-tuning is better for a specific style/tone or when inference cost matters more.
Example:A customer-service chatbot: RAG over FAQs (updatable). A brand-voice copy generator: fine-tuning (consistent style).
How we apply it →Model specialized in generating embeddings (numeric vectors) from text. Popular in 2026: text-embedding-3-large (OpenAI), voyage-large-2 (Anthropic/Voyage), bge-large (BAAI, open).
Example:text-embedding-3-small turns 'lease agreement' into a 1,536-dimension vector. Other semantically similar texts will have nearby vectors.
Búsqueda Semántica (Semantic Search)
Search based on meaning (via embeddings) instead of exact keywords. Finds 'used car' even when the document says 'second-hand vehicle'.
Example:A legal search engine with semantic search finds relevant case law even when the ruling uses different vocabulary from the query.
Running an LLM on your own infrastructure (servers, local GPUs) instead of cloud APIs. Advantage: data control, fixed cost, latency. Disadvantage: requires expensive GPUs + ops expertise.
Example:A public hospital self-hosts Llama 4 on local H100 GPUs to ensure patient data never leaves the datacenter.