RE-call MCP Memory Server

Memory that abstains instead of guessing.

RE-call is agent memory in a local SQLite file or your own PostgreSQL with pgvector. Each result carries a verdict, confidence, and provenance, while unsupported questions are refused instead of answered by the nearest match.

What it is · For agents · How it works · Start with Lite · Install and integrate

What is RE-call

RE-call is agent memory in a local SQLite file or your own PostgreSQL database. It indexes source documents and keeps validity, lineage, confidence, and provenance attached to every result.

Vector search returns nearby text. RE-call also checks whether that text is current, supported, and trustworthy enough for the query. A superseded claim is marked superseded; a result that does not clear the calibrated trust gate becomes ABSTAIN with a reason. Declared supersession makes the current memory win over stale but similar memory.

The default path uses local embeddings plus hybrid dense and keyword retrieval. PostgreSQL uses its full text search; Lite uses SQLite FTS5. It needs no memory-layer LLM call. Additional retrieval, reasoning, and structured-fact modules are optional.

For the agent reading this, RE-call for agents explains the experience loop and how to use persistent memory as a trustworthy past rather than an unverified scratchpad.

How it works

On PostgreSQL, RE-call builds an immutable, calibrated generation and serves queries against that pinned generation. Lite binds calibration to its single-file corpus. Every search, including the reasoning and fact paths, goes through trusted search and the trust gate.

The diagram is interactive on the project site: click any box to see the source lines it describes. A step by step view of one recall_search call follows a single search through its refusal, abstention and answer paths. Both are generated from the sources in docs/diagrams.

Text version of the diagram, with each box linked to its file

Solid arrows are the default path. Dashed arrows are opt in or reasoning only: the reranker, graph expansion, and the answer provider. Each box links to the file that implements it.

flowchart LR

subgraph group_entry["Entry points"] node_cli["recall CLI commands"] node_mcp["MCP server tool handlers"] node_sdk["Agent SDK in process"] end

subgraph group_build["Generation build"] node_manifest["Source manifest immutable input"] node_generations["Generation manager build, validate, promote"] node_parser["Parse and chunk documents to chunks"] node_embedder["Embedder local or hosted API"] node_graph_build["Semantic graph entities, relations"] node_calibration["Calibration certified threshold"] end

subgraph group_serve["Trusted retrieval"] node_trusted_search["Trusted search query orchestrator"] node_gen_store["Generation store pinned generation"] node_retriever["Hybrid retriever dense, full text, RRF"] node_reranker["Reranker opt in"] node_trust_gate{{"Trust gate verdict or ABSTAIN"}} end

subgraph group_reason["Reasoning"] node_reasoner["Reasoning query evidence bundle, plan"] node_graph_expansion["Graph expansion one hop, before trust"] node_answer["Answer provider opt in LLM"] end

subgraph group_facts["Provenance and facts"] node_provenance["Provenance controller fact review"] node_ledger["Fact ledger append only"] end

node_caller(("Agent or user caller")) node_postgres[("PostgreSQL + pgvector generations, chunks, graph")]

node_caller -->|"runs"| node_cli node_caller -->|"tool calls"| node_mcp node_caller -->|"imports"| node_sdk node_sdk -->|"reuses handlers"| node_mcp node_cli -->|"generation build"| node_generations node_mcp -->|"ingest uploads"| node_generations node_generations -->|"reads sources"| node_manifest node_generations -->|"parses, chunks"| node_parser node_generations -->|"embeds chunks"| node_embedder node_generations -->|"builds graph"| node_graph_build node_generations -->|"requires certified"| node_calibration node_generations -->|"writes generation"| node_postgres node_graph_build -->|"writes graph"| node_postgres node_cli -->|"calibrate, publish"| node_calibration node_calibration -->|"stores threshold"| node_postgres node_cli -->|"search"| node_trusted_search node_mcp -->|"search, evidence"| node_trusted_search node_trusted_search -->|"pins generation"| node_gen_store node_gen_store -->|"reads active"| node_postgres node_trusted_search -->|"retrieves"| node_retriever node_retriever -->|"embeds query"| node_embedder node_retriever -->|"dense, full text"| node_gen_store node_retriever -.->|"reorders"| node_reranker node_trusted_search -->|"evaluates"| node_trust_gate node_mcp -->|"reasoning query"| node_reasoner node_reasoner -->|"retrieves"| node_trusted_search node_trusted_search -.->|"expands pre trust"| node_graph_expansion node_graph_expansion -.->|"same generation graph"| node_postgres node_reasoner -.->|"cited answer"| node_answer node_mcp -->|"apply fact"| node_provenance node_provenance -->|"fresh search"| node_trusted_search node_provenance -->|"appends"| node_ledger node_ledger -->|"stores"| node_postgres

click node_cli "https://github.com/GiulioDER/RE-call/blob/master/recall/cli.py" click node_mcp "https://github.com/GiulioDER/RE-call/tree/master/recall_mcp" click node_sdk "https://github.com/GiulioDER/RE-call/blob/master/recall_agent/memory.py" click node_manifest "https://github.com/GiulioDER/RE-call/blob/master/recall/manifest.py" click node_generations "https://github.com/GiulioDER/RE-call/blob/master/recall/generations.py" click node_parser "https://github.com/GiulioDER/RE-call/blob/master/recall/document.py" click node_embedder "https://github.com/GiulioDER/RE-call/blob/master/recall/embeddings.py" click node_graph_build "https://github.com/GiulioDER/RE-call/blob/master/recall/semantic_graph/_build.py" click node_calibration "https://github.com/GiulioDER/RE-call/blob/master/recall/calibration_v2.py" click node_trusted_search "https://github.com/GiulioDER/RE-call/blob/master/recall/trust.py" click node_gen_store "https://github.com/GiulioDER/RE-call/blob/master/recall/generation_store.py" click node_retriever "https://github.com/GiulioDER/RE-call/blob/master/recall/retriever.py" click node_reranker "https://github.com/GiulioDER/RE-call/blob/master/recall/rerank.py" click node_trust_gate "https://github.com/GiulioDER/RE-call/blob/master/recall/trust.py" click node_reasoner "https://github.com/GiulioDER/RE-call/blob/master/recall/reasoning.py" click node_graph_expansion "https://github.com/GiulioDER/RE-call/blob/master/recall_mcp/graph_expansion.py" click node_answer "https://github.com/GiulioDER/RE-call/blob/master/recall/answer_provider.py" click node_provenance "https://github.com/GiulioDER/RE-call/blob/master/recall/provenance_controller.py" click node_ledger "https://github.com/GiulioDER/RE-call/blob/master/recall/fact_ledger.py" click node_postgres "https://github.com/GiulioDER/RE-call/tree/master/recall/migrations"

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Ordinary recall search follows the direct path. Explicit reasoning accepts graph_expansion: auto is the default and resolves to bounded one hop expansion for every nonempty query; off keeps direct retrieval only; one-hop forces the graph path. The CLI uses --graph-expansion auto|off|one-hop; the MCP tool uses graph_expansion="auto"|"off"|"one_hop". Graph neighbors are generation bound, direct candidates remain first, and expanded candidates must clear the same trust boundary before they can support a cited answer.

The opt in choices attach to different points in the system:

For details, see the architecture writeup, provenance controller, and API reference.

Quickstart

For one project's memory on