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context-graph

Context graph vs vector database: which one your agent should query

A vector database retrieves the chunk closest to your query. A context graph answers from how your work connects. Here is the difference, and which one your agent actually needs.

Teams building an AI agent on their own data usually reach for a vector database first: Pinecone, or something like it, holding embeddings of every doc. Suda is built on a context graph instead. Here is what that choice actually changes, and when each one is the right call.

The one-line difference

A vector database finds the chunk whose embedding sits closest to your query. A context graph finds the facts that actually answer it, current and connected. Nearness in vector space is not the same thing as being correct.

What a vector database is good at

A vector database is a similarity index. You embed your documents, embed the query, and pull back the nearest neighbors. It is fast, well understood, and fine for its job: “find text like this.” Point it at a static corpus, a docs site, a research library, and it holds up well.

The trouble starts once your data changes and disagrees with itself, which is exactly what happens inside a company:

  • No sense of time. A policy from March and a policy from October embed close together if the wording is similar. The database has no way to tell which one is current.
  • No sense of authority. It does not know a decision logged in Linear overrides a note left in Notion months ago.
  • No sense of structure. It returns the nearest paragraph, not the three or four connected facts that together make up the real answer.

None of this is a bug. A vector database was never built to model relationships or freshness, only similarity.

What a context graph adds

A context graph stores the facts scattered across your tools and the relationships between them: who owns a decision, what it superseded, which project it belongs to. When an agent asks a question, the graph walks those relationships and hands back a current, coherent answer instead of a pile of similar-sounding snippets.

That structure also cuts what reaches the model. Because the graph sends only the context a question needs rather than every chunk that resembles it, Suda passes about 85% less text per answer than raw retrieval. Fewer tokens in, less noise for the model to sort through, lower cost per query.

And it stays current on its own. Stale facts retire and conflicts resolve as your tools change, so nobody is re-embedding or re-chunking a corpus by hand.

Side by side

Vector databaseContext graph (Suda)
Retrieves byEmbedding similarityHow facts connect
Knows what is currentNoYes, stale facts retire
Resolves contradictionsReturns both, agent guessesResolves to the current fact
Answers that span toolsOne chunk at a timeWalks the connected facts
Context sent to modelEvery similar chunkOnly what is needed (~85% less)
UpkeepRe-index, re-chunk, cleanSelf-updating

When a vector database is still the right call

If your corpus is static and nothing in it contradicts anything else, a vector database is enough. Documentation search, a fixed knowledge library, semantic search over a product catalog: none of that needs a graph.

The moment your context lives across Notion, Slack, and Linear, keeps changing, and includes decisions that override each other, similarity search stops being enough. That is the gap a context graph closes.

Where Suda fits

Suda ingests from more than 700 sources, builds the graph, and keeps it updated as your tools change. Any AI agent reads it over MCP, so the agents already in your stack can query it directly, and you can ask context straight from Slack. Access is permissioned throughout.

Getting started is one command:

npx suda connect

For the same comparison against RAG more broadly, see context graph vs RAG. For the underlying concept, start with what is a context graph.