hm_update

hm_update changes an existing memory instead of creating a duplicate. It works on a node (by key) or on a single edge or hyperedge (by edge_id).

Update a node

Parameter	Type	Description
`key`	string	Required for a node update. The node to change.
`description`	string	A new description. It replaces the old one: write what is true now (80–300 characters), never the old text plus an appended “UPDATE” paragraph.
`data`	object	The node’s structured data. Replaces the existing `data` object entirely, so send every field you want to keep. Put history and corrections here.
`node_type`	string	Move the node to another canonical type.
`search_text`	string	Extra keywords to index.
`assets`	string[]	Asset references.

Fields you don’t send are left as they are. When the description changes, HyperMemory re-indexes the node for search and re-runs person and organization detection; any update sets enrichment_status back to pending.

If the node was wrong, say in data what was corrected and how it was verified — for example {"corrected": {"field": "launch_date", "from": "2026-10-01", "to": "2026-11-02", "verified_by": "release calendar"}}. Later sessions can then trust the correction.

Update an edge

Parameter	Type	Description
`edge_id`	string	Required for an edge update. The binary edge’s id, as returned by `hm_get_nodes`. Takes precedence over `key`.
`description`	string	New wording of the relationship’s explanation.
`data`	object	Structured facts about the connection, merged into the edge’s existing data. `null` clears it.
`edge_version`	integer	Optional `write_version` you last read. If the edge changed since, the update is refused with `edge_version_conflict` (409), so concurrent writers don’t overwrite each other.

An edge’s endpoints and relationship type are immutable. To change them — or to change a hyperedge, which can’t be updated in place — delete it with hm_forget and recreate it with hm_add_relationships.

Response

Field	Description
`updated`	The node key or edge id that was changed.
`edge_id`	On an edge update, the edge that was changed.
`memory_version`	The graph’s version after the write.
`replayed`	`true` when this update had already been applied (safe retry).

Examples

{
  "key": "fact_launch_date",
  "description": "Product launches on 2026-11-02, moved from 2026-10-01 after the security review.",
  "data": {
    "date": "2026-11-02",
    "status": "scheduled",
    "corrected": { "field": "date", "from": "2026-10-01", "verified_by": "release calendar" }
  }
}

{
  "edge_id": "6f1d2c0a-8b4e-5a37-9c21-3e7f5b9d0a14",
  "edge_version": 3,
  "description": "Alice has led Project Phoenix since its kickoff in January 2026."
}

Equivalents

curl -X POST https://api.hypermemory.io/api/v1/memory/update \
  -H "Authorization: Bearer $HYPERMEMORY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"key":"fact_launch_date","description":"Product launches on 2026-11-02, moved from 2026-10-01 after the security review."}'