---
title: "Service: /members/{member}/groups/{group}/uris/{uri}/editpsmlproperty [POST]"
source: https://dev.pageseeder.com/api/services/edit-psml-property-POST.html
description: "This API endpoint edits properties in PSML fragments. It modifies a specified property's value within a URI's fragment, requiring either fragment ID or old value to locate the target. Contributor permissions required."
last_updated: 2026-09-02T11:36:11+10:00
document_type: api_endpoint
operation_id: psml-POST
resource_id: psml
path_template: /members/{member}/groups/{group}/uris/{uri}/editpsmlproperty
http_method: POST
api_category: psml
implementation_version: 6.2005
api_since: 5.5912
deprecated_since: null
obsolete_since: null
api_support: supported
cache_control: N/A
generated_at: 2026-09-02
tokens: ~464
---

# /members/\{member\}/groups/\{group\}/uris/\{uri\}/editpsmlproperty \[POST\]

## Description

Edit a property found in a [fragment](../../reference/glossary/fragment.md) of the URI provided.

The fragment can be specified using the parameter `fragment`. If it is not present, the parameter `oldvalue` must be specified as it is used to retrieve the fragment from the content.

If the parameters `fragment` and `oldvalue` are both specified, only the properties in that fragment and matching the old value specified are edited.

Only the first fragment containing the property found (if not specified) is modified but all the occurrences of the properties matching the parameters provided are edited in that fragment.

> **Note:** This service cannot be used for properties with `datatype="[markup|xref|link]"` or `multiple="true"`.

## Parameters

| Name | Description | Required | Type | Default |
| --- | --- | --- | --- | --- |
| name | The name of the property to edit | yes | string |  |
| newvalue | The new value for the property (XML markup is treated as text) | yes | string |  |
| fragment | The fragment `ID` to edit (required if oldvalue is not specified). Using `default` edits metadata properties | maybe | string |  |
| oldvalue | The old value of the property (required if fragment is not specified) | maybe | string |  |

## Permission

This service requires contributor or higher.

## Response

The XML output follows this format:

```xml

<property-modification fragment="123" uriid="456">
  <property name="mylabel" value="my new value" />
</property-modification> 
```

## Error Handling

| Code | Cause / Description |
| --- | --- |
| 0x1206 | Invalid media type |
| 0x120B | Error processing XRefs |
| 0x120C | Error creating fragment |
| 0x120D | Content validation error |
| 0x1218 | Fragment not found with specified content |