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Reference-faithful retrieval, no LLM in the loop

2026. Deterministic retrieval is not a compromise — it’s a feature.

There’s a seductive idea in the agent-memory space: make recall smart by making it generate. Ask the model what’s relevant, let the model decide what to retrieve, let the model write the memory. The problem is that a model deciding what to retrieve is a model you can’t audit and can’t budget. Every call is a token. Every answer is a fresh coin-flip. And “why did the agent recall this?” has an answer no reviewer can verify.

We took the other path: deterministic, reference-faithful retrieval, with no LLM in the loop. Recall never has to think. A static, local embedding model plus a deterministic pipeline answer the question — zero per-query cost, zero data egress, zero latency on a 4 GB ARM device.

This isn’t “dumb” retrieval — it’s research-grade retrieval, made deterministic

Each mechanism in the retrieval stack implements a published technique without the LLM its authors used:

TechniqueReferenceDeterministic here
Bi-temporal factsGraphiti (Zep)src/temporal.rs marker extraction + validity filters
Submodular evidence packingarXiv:2607.00725 (+5.1 F1)lazy-greedy under a token knapsack, MMR diversity
Typed graph pathsarXiv:2607.00339 (TRACE)typed hop chains, bounded BFS, ?at= validity
Personalized PageRank graph legHippoRAG 2pure-Rust CSR power iteration, damping=0.5
Hub dampening + type weightsGAAMA, MemORAIw_ij·min(1,θ/deg), tagged_with→0.1
Calibrated abstentionroadmap evidence-gatingestimator-driven ClarifyQuery → “I don’t know”

The key move: take the arithmetic, drop the LLM. Hub dampening is a formula, not a model. PPR is a power iteration, not a generation call. Every mechanism has a documented ceiling (see docs/research/), because a deterministic system is one you can state the limits of — which is exactly why it’s defensible in a bakeoff.

What you actually get

  • Reproducibility: the same query returns the same answer, every time. You can pin behavior in a test, not pray it holds.
  • No token bill: recall and writes cost nothing per query. The < 5 W manifesto is literal.
  • Verifiable provenance: every hit carries its per-retriever rank, fused score, and evidence — source_uri + revision_id linking to the exact source revision, with byte-offset highlights within the revealed snippet. The server never fabricates a snippet.
  • An honest ceiling: when the estimator says the query is too ambiguous, the system abstains — it says “I don’t know” rather than top-1 garbage. (See the abstention explainer.)

Why “no LLM in the loop” is the 2026 differentiator

Every competitor’s cost is “an LLM call per query.” Yours is 0. Every competitor’s answer to “why did it recall this?” is a hand-wave. Yours is a recorded, replayable decision path. In an era of agentic-security pressure and per-query cost scrutiny, deterministic retrieval is not the cheap fallback — it is the defensible choice.

The takeaway: if an agent’s memory can be verified and budgeted, it can be trusted at enterprise scale. Retrieval that generates is retrieval you pay for every turn and can’t replay. Retrieval that computes is retrieval you can pin, audit, and run on a device you own.

Deep dives: docs/research/. The framework-agnostic story continues in the next post.