[user properties 1/2] Keep undeclared properties out of the vector store - #1702

Purpose of the change

The event backend wrote every property of an event into its vector record and mapped the caller's whole filter onto the vector store, so a user key a deployment never declared was both stored and filtered there: on Qdrant and Milvus as unindexed payload a filtered query scans for. Now an undeclared key stays off the vector store, so a tenant's undeclared properties cannot shape what it stores or scans; #1670, stacked on this, removes the per-project declaration, so no tenant key reaches it at all. The segment store already holds every property and already receives the whole filter for the context windows, so the vector side only duplicated work the segment store does anyway.

The vector record now carries the keys the collection declares: EventMemory's reserved timestamp, the _-prefixed system properties an adapter stamps on the event, and the keys a project's properties_schema declares, until #1670 removes that option (collection.config.indexed_properties_schema). The vector store is queried with the conjuncts of the filter that name only such fields; a conjunct is dropped whole when any field under it is undeclared, so dropping only ever widens the vector search, and the segment store narrows it back on the windows. An undeclared key never reaches the vector store.

filter_fields joins the filter parser: every field name a tree addresses. Tests: an undeclared property stays on the segment and off the record; a conjunct on an undeclared property reaches only the segment store; an undeclared property under an OR leaves the vector search unfiltered; filter_fields names every field under every node.

This is the routing half of what was #1628 on speedkick (its store-side half, the stores rejecting undeclared keys, is deferred to after #1627); it is re-derived onto #1736's collection shape from the same commit, where the segment store, not the vector record, maps a derivative to its segment.

Part of the fix for #1781.

Stack

21 open PRs: three independent PRs, and the vector store tree of short parallel branches. Every PR in the tree has feat/horizontal-scaling as its GitHub base, and the independent PRs have main. The branches are in a fork, and a pull request can target only this repository's branches, so the on column gives the order the PRs build on each other. A stacked PR's diff on GitHub includes the PRs under it until they merge.

Independent of the vector store tree, directly on main:

The vector store tree. Each PR builds on the one in its on column; PRs on the same parent are parallel branches and do not depend on each other. #1631 is closed, superseded by #1733–#1736, which hold its changes split in four, with review changes since. #1702 and #1670 sit beneath #1627, whose code depends on them. Until the PRs under it merge, their changes show in a stacked PR's diff.

This PR is its one commit, b1c3242fe, directly on feat/horizontal-scaling. #1670 is stacked on it.

Verification

At this PR's head b1c3242fe, on 2026-10-09, on feat/horizontal-scaling with #1813 merged: ruff check and ruff format --check clean; ty check clean as CI runs it (uv run --frozen --all-extras ty check --project packages/server); uv lock --check clean.

Before the rebase onto #1813's merge: At this PR's head 6cdbe0733, on 2026-10-09: ruff check and ruff format --check clean; ty check clean as CI runs it (uv run --frozen --all-extras ty check --project packages/server); uv lock --check clean; the episodic memory and filter tests pass, 448 tests. The full suites have not run on this tree, which is new with #1670 above it; with #1670 beneath it, the server suite without integration tests last passed at 9031d25f4, on 2026-10-08, 2166 tests, and the integration tests of the vector stores, the resource manager, episodic memory, and semantic storage at 9031d25f4, on 2026-10-08, 689 tests, against PostgreSQL 16, Neo4j, Qdrant 1.19.1, and Milvus 2.6.24 in containers.

🤖 Generated with Claude Code

https://claude.ai/code/session_01ESpWYTmCR7X3bJEpoA8SAn