Skip to main content
The builtin engine is the default memory backend. It stores your memory index in a per-agent SQLite database and needs no extra dependencies to get started.

​
What it provides

  • Keyword search via FTS5 full-text indexing (BM25 scoring).
  • Vector search via embeddings from any supported provider.
  • Hybrid search that combines both for best results.
  • CJK support via trigram tokenization for Chinese, Japanese, and Korean.
  • sqlite-vec acceleration for in-database vector queries (optional).

​
Getting started

If you have an API key for OpenAI, Gemini, Voyage, or Mistral, the builtin engine auto-detects it and enables vector search. No config needed. To set a provider explicitly: 
{
  agents: {
    defaults: {
      memorySearch: {
        provider: "openai",
      },
    },
  },
}
Without an embedding provider, only keyword search is available.

​
Supported embedding providers

ProviderIDAuto-detectedNotes
OpenAIopenaiYesDefault: text-embedding-3-small
GeminigeminiYesSupports multimodal (image + audio)
VoyagevoyageYes
MistralmistralYes
OllamaollamaNoLocal, set explicitly
LocallocalYes (first)GGUF model, ~0.6 GB download
Auto-detection picks the first provider whose API key can be resolved, in the order shown. Set memorySearch.provider to override.

​
How indexing works

FluffBuzz indexes MEMORY.md and memory/*.md into chunks (~400 tokens with 80-token overlap) and stores them in a per-agent SQLite database.
  • Index location: ~/.fluffbuzz/memory/<agentId>.sqlite
  • File watching: changes to memory files trigger a debounced reindex (1.5s).
  • Auto-reindex: when the embedding provider, model, or chunking config changes, the entire index is rebuilt automatically.
  • Reindex on demand: fluffbuzz memory index --force
You can also index Markdown files outside the workspace with memorySearch.extraPaths. See the configuration reference.

​
When to use

The builtin engine is the right choice for most users:
  • Works out of the box with no extra dependencies.
  • Handles keyword and vector search well.
  • Supports all embedding providers.
  • Hybrid search combines the best of both retrieval approaches.
Consider switching to QMD if you need reranking, query expansion, or want to index directories outside the workspace. Consider Honcho if you want cross-session memory with automatic user modeling.

​
Troubleshooting

Memory search disabled? Check fluffbuzz memory status. If no provider is detected, set one explicitly or add an API key. Stale results? Run fluffbuzz memory index --force to rebuild. The watcher may miss changes in rare edge cases. sqlite-vec not loading? FluffBuzz falls back to in-process cosine similarity automatically. Check logs for the specific load error.

​
Configuration

For embedding provider setup, hybrid search tuning (weights, MMR, temporal decay), batch indexing, multimodal memory, sqlite-vec, extra paths, and all other config knobs, see the Memory configuration reference.