> ## Documentation Index > Fetch the complete documentation index at: https://docs.myme.so/llms.txt > Use this file to discover all available pages before exploring further. # Update an item > Updates an item's properties, tier, timestamp, or natural-key `source_id`. Properties shallow-merge into the existing row (unmentioned keys keep their values). The optional `version` field enables optimistic concurrency — pass the version the caller is editing from; a mismatch returns `409 version_conflict` with the three-way context (current, ancestor, conflicting fields, resolved merge policy) the client needs to resolve. See [Conflicts](/concepts/conflicts) and [Errors — version_conflict](/api/errors#version-conflict). The `edges` block has replace-all-for-specified-types semantics: any edge_type listed wipes existing outbound edges of that type from this item, then creates new edges to each listed target. Empty array for an edge_type deletes all edges of that type. Unmentioned edge types are untouched. Tier and timestamp updates are last-writer-wins and never produce a version conflict. The `source_id` field repoints the item at a new natural key under the item's `source`. The `(source, source_id)` tuple is unique per tenant — collisions with a different existing item return `409 source_id_conflict`. PATCHing the value the item already carries is a no-op success. Used by the sync agent to preserve item identity through file renames. ## OpenAPI ````yaml /openapi.json patch /items/{id} openapi: 3.1.0 info: title: Marfa API version: 4.2.0 description: Typed data layer for structured personal data servers: [] security: [] paths: /items/{id}: patch: tags: - Items summary: Update an item description: >- Updates an item's properties, tier, timestamp, or natural-key `source_id`. Properties shallow-merge into the existing row (unmentioned keys keep their values). The optional `version` field enables optimistic concurrency — pass the version the caller is editing from; a mismatch returns `409 version_conflict` with the three-way context (current, ancestor, conflicting fields, resolved merge policy) the client needs to resolve. See [Conflicts](/concepts/conflicts) and [Errors — version_conflict](/api/errors#version-conflict). The `edges` block has replace-all-for-specified-types semantics: any edge_type listed wipes existing outbound edges of that type from this item, then creates new edges to each listed target. Empty array for an edge_type deletes all edges of that type. Unmentioned edge types are untouched. Tier and timestamp updates are last-writer-wins and never produce a version conflict. The `source_id` field repoints the item at a new natural key under the item's `source`. The `(source, source_id)` tuple is unique per tenant — collisions with a different existing item return `409 source_id_conflict`. PATCHing the value the item already carries is a no-op success. Used by the sync agent to preserve item identity through file renames. parameters: - schema: type: string required: true name: id in: path requestBody: content: application/json: schema: type: object properties: properties: type: object additionalProperties: nullable: true version: type: integer minimum: 0 force_snapshot: type: boolean tier: type: string enum: - library - feed timestamp: type: string source_id: type: string edges: type: object additionalProperties: type: array items: type: string responses: '200': description: Item updated content: application/json: schema: type: object properties: item: type: object properties: id: type: string type: type: string properties: type: object additionalProperties: nullable: true state: type: string enum: - active - archived - trashed - revoked tier: type: string enum: - library - feed tenant_id: type: string nullable: true version: type: number schema_version: type: integer source: type: string source_id: type: string device: type: string capture_latitude: type: number capture_longitude: type: number timestamp: type: string created_at: type: string updated_at: type: string edges: type: object additionalProperties: type: object properties: edges: type: array items: type: object properties: id: type: string tenant_id: type: string nullable: true source_id: type: string target_id: type: string edge_type: type: string properties: type: object additionalProperties: nullable: true created_at: type: string updated_at: type: string required: - id - source_id - target_id - edge_type - properties - created_at - updated_at has_more: type: boolean next_cursor: type: string required: - edges - has_more extensions: type: object additionalProperties: type: object additionalProperties: nullable: true required: - id - type - properties - state - version - schema_version - source - timestamp - created_at - updated_at metadata: type: object properties: item_id: type: string tags: type: array items: type: string extensions: type: object additionalProperties: nullable: true required: - item_id - tags - extensions required: - item - metadata '400': description: Validation error content: application/json: schema: type: object properties: error: type: object properties: code: type: string enum: - validation_error - missing_required_field - invalid_id - invalid_properties - edge_constraint_violation - edge_cycle message: type: string details: type: object additionalProperties: nullable: true required: - code - message required: - error '401': description: Unauthorized content: application/json: schema: type: object properties: error: type: object properties: code: type: string enum: - unauthorized message: type: string details: type: object additionalProperties: nullable: true required: - code - message required: - error '404': description: Item not found content: application/json: schema: type: object properties: error: type: object properties: code: type: string enum: - item_not_found - edge_type_not_found message: type: string details: type: object additionalProperties: nullable: true required: - code - message required: - error '409': description: >- Version conflict (optimistic-concurrency mismatch on `properties`) or `source_id_conflict` (target natural key already in use by another item under the item's `source`). content: application/json: schema: anyOf: - type: object properties: error: type: object properties: code: type: string enum: - version_conflict status: type: number enum: - 409 required: - code - status current: type: object properties: version: type: number properties: type: object additionalProperties: nullable: true required: - version - properties ancestor: type: object properties: version: type: number properties: type: object additionalProperties: nullable: true required: - version - properties conflicting_fields: type: array items: type: string merge_policy: type: object properties: fields: type: object additionalProperties: type: string enum: - last_writer_wins - keep_both_copies default: type: string enum: - last_writer_wins - keep_both_copies required: - error - current - ancestor - conflicting_fields - merge_policy - type: object properties: error: type: object properties: code: type: string enum: - source_id_conflict message: type: string details: type: object additionalProperties: nullable: true required: - code - message required: - error security: - bearerAuth: [] components: securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: API Key or OAuth Token description: Pass an API key (marfa_k1_...) or OAuth access token (marfa_at_...) ````