TCall

A tiny search engine over ephemeral sessions, powered by Glyph MinHash fingerprints and backed by SQLite.

How it works

Create a session with any name. Sessions expire after 5 minutes of inactivity; touching a live session (preserve/recall/create) extends it.
Preserve aggregates a set of observations into a single Glyph collection glyph (period-min hash). Only that serialized glyph is stored — the raw observations are never written to the database.
Recall rehydrates every preserved observation glyph, builds an in-memory index, searches it with a glyph of the query, and returns the raw context text for the top-limit hits.

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Data model

Table	Columns	Purpose
`sessions`	`name`, `last_activity`	Expiry (5 min inactivity)
`observations`	`id`, `session`, `glyph`, `context`	Serialized collection glyph + raw context keyed to it

Endpoints

All endpoints take JSON and return JSON.

`POST /session/create`

{ "name": "meeting-notes" }

→ 200: { ok, session, expiresInSeconds, expiresAt }

`POST /session/preserve`

{
  "session": "meeting-notes",
  "observations": [
    "the new pricing is $49 per seat for the pro tier",
    "annual plans get a 20% discount"
  ],
  "context": "Pricing decision: pro tier $49/seat, 20% off annual plans."
}

observations are fingerprinted and discarded; only context is stored, keyed to the aggregated glyph. → 200: { ok, id }

`POST /session/recall`

{ "session": "meeting-notes", "query": "what did we decide about pricing?", "limit": 3 }

→ 200: { ok, query, total, results: [{ id, similarity, context }] }

Notes

A session that is inactive for 5 minutes is wiped (observations deleted) and must be recreated. Sticky sessions (e.g. test-notes) are exempt and never expire.
Recall uses an exact scan (index.New({ mode: "direct" })); the default Softmax collection aggregator compares poorly against raw query glyphs, so TCall uses CollectionAggregatorMin.
Endpoint files: main.ts · lib.ts