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Update work package

update_work_package

Modify any writable work package field—assign, re-parent, change status, schedule, progress, or custom fields—using optimistic locking and return the updated package with its new lock_version.

Instructions

Change any writable field of a work package, with optimistic locking done properly.

Use it to assign or unassign, move a status forward, re-schedule, re-parent, set progress, or write custom fields — one tool instead of many.

Returns the updated work package in full detail, including the new lock_version to use for a follow-up edit.

Pitfalls: omitted parameters are left alone, while passing null clears a field (assignee, responsible, version, sprint, parent, dates, description). A 409 error means somebody else changed the work package first — the error carries the fresh lock_version and the conflicting fields, so re-read and retry deliberately.

Ids come from get_work_package / list_work_packages; status, priority, type and version values come from get_project_metadata; sprint ids come from list_sprints.

Input Schema

Name	Required	Description	Default
`id`	Yes	Work package id to change (#1234).
`date`	No	Milestone date (YYYY-MM-DD); only valid on milestone types.	__unchanged__
`type`	No	New type as a name or numeric id. Cannot be cleared.
`notify`	No	Email notifications for this change.
`sprint`	No	Numeric sprint id from list_sprints; null removes it.	__unchanged__
`status`	No	New status as a name or id; invalid transitions list the reachable statuses.
`subject`	No	New title. Omit to leave unchanged; cannot be cleared.
`version`	No	Numeric version id; null removes it.	__unchanged__
`assignee`	No	Numeric user id; omit to leave unchanged, null (or 'none') to unassign.	__unchanged__
`due_date`	No	ISO date (YYYY-MM-DD); null clears it.	__unchanged__
`priority`	No	New priority as a name or numeric id.
`parent_id`	No	Re-parent under another id; null detaches to top level (the only hierarchy tool).	__unchanged__
`start_date`	No	ISO date (YYYY-MM-DD); null clears it.	__unchanged__
`description`	No	New markdown body; omit to leave unchanged, null to empty it. Replaces the whole text; read it first to append instead.	__unchanged__
`responsible`	No	Numeric id of the accountable person; null clears it.	__unchanged__
`lock_version`	No	The `lock_version` from get_work_package. Passing it makes a concurrent edit fail loudly (409); omitting it fetches and echoes the current version — safe, but a wider conflict window.
`story_points`	No	Story points as a non-negative integer.
`custom_fields`	No	Custom field writes keyed by wire key or display name, e.g. {'Severity': 'High'}. Unknown or non-writable keys fail listing the valid ones. Only passed keys are touched.
`estimated_hours`	No	Estimate in hours, decimal.
`percentage_done`	No	Progress 0-100.
`remaining_hours`	No	Remaining work in hours, decimal.
`target_versions`	No	Target version ids; [] clears, omit leaves unchanged. Multiple values need instance support. Mutually exclusive with version.

Output Schema

Name	Required	Description	Default
`id`	No
`date`	No
`type`	No
`notes`	No
`author`	No
`parent`	No
`sprint`	No
`status`	No
`project`	No
`subject`	No
`version`	No
`assignee`	No
`category`	No
`due_date`	No
`priority`	No
`available`	No
`created_at`	No
`display_id`	No
`start_date`	No
`updated_at`	No
`description`	No
`responsible`	No
`spent_hours`	No
`lock_version`	No
`story_points`	No
`custom_fields`	No
`project_phase`	No
`estimated_hours`	No
`percentage_done`	No
`remaining_hours`	No
`target_versions`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed127 schema fields changedv0.4.0Oct 24, 2026

removedOutput schema / description

Removed value: -"Detail projection plus the milestone ``date`` field.\n\nMilestone types carry a single ``date`` instead of ``start_date``/\n``due_date``; both shapes are surfaced so a caller never has to guess."

changedOutput schema / properties / assignee / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / assignee / default
```
Removed value: -null
```
removedOutput schema / properties / assignee / description
```
Removed value: -"Assigned user or group."
```

changedOutput schema / properties / author / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / author / default
```
Removed value: -null
```
removedOutput schema / properties / author / description
```
Removed value: -"Creating user."
```
removedOutput schema / properties / available / default
```
Removed value: -null
```

removedOutput schema / properties / available / description

Removed value: -"Feature availability for this WP: dev links, meetings, files."

changedOutput schema / properties / category / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / category / default
```
Removed value: -null
```
removedOutput schema / properties / category / description
```
Removed value: -"Category."
```

removedOutput schema / properties / created_at / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / created_at / default
```
Removed value: -null
```
removedOutput schema / properties / created_at / description
```
Removed value: -"ISO 8601 UTC timestamp."
```
addedOutput schema / properties / created_at / type
```
Added value: +[
+  "string",
+  "null"
+]
```
removedOutput schema / properties / custom_fields / description
```
Removed value: -"Always a list; empty when none are set."
```
removedOutput schema / properties / custom_fields / items / description
```
Removed value: -"Canonical custom-field read shape."
```
removedOutput schema / properties / custom_fields / items / properties / key / description
```
Removed value: -"Wire key, e.g. 'customField12'."
```

removedOutput schema / properties / custom_fields / items / properties / name / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / custom_fields / items / properties / name / default
```
Removed value: -null
```
removedOutput schema / properties / custom_fields / items / properties / name / description
```
Removed value: -"Display name, e.g. 'Severity'."
```
addedOutput schema / properties / custom_fields / items / properties / name / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / custom_fields / items / properties / type / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / custom_fields / items / properties / type / default
```
Removed value: -null
```
removedOutput schema / properties / custom_fields / items / properties / type / description
```
Removed value: -"Schema type, e.g. 'list', 'string'."
```
addedOutput schema / properties / custom_fields / items / properties / type / type
```
Added value: +[
+  "string",
+  "null"
+]
```
removedOutput schema / properties / custom_fields / items / properties / value / default
```
Removed value: -null
```
removedOutput schema / properties / custom_fields / items / properties / value / description
```
Removed value: -"Scalar value or resolved name(s)."
```

changedOutput schema / properties / custom_fields / items / properties / value_ids / anyOf

Previous value: -[
-  {
-    "items": {
-      "anyOf": [
-        {
-          "type": "integer"
-        },
-        {
-          "type": "string"
-        }
-      ]
-    },
-    "type": "array"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "items": {
+      "type": [
+        "integer",
+        "string"
+      ]
+    },
+    "type": "array"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / custom_fields / items / properties / value_ids / default
```
Removed value: -null
```
removedOutput schema / properties / custom_fields / items / properties / value_ids / description
```
Removed value: -"Ids for list/user/version custom fields."
```

removedOutput schema / properties / date / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / date / default
```
Removed value: -null
```

removedOutput schema / properties / date / description

Removed value: -"Milestone date (ISO YYYY-MM-DD); null for non-milestones."

addedOutput schema / properties / date / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / description / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / description / default
```
Removed value: -null
```

removedOutput schema / properties / description / description

Removed value: -"Description as markdown (raw); html is dropped."

addedOutput schema / properties / description / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / display_id / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / display_id / default
```
Removed value: -null
```

removedOutput schema / properties / display_id / description

Removed value: -"Human-facing id as the instance renders it. Matches the numeric id unless the instance uses semantic identifiers (17.x, e.g. 'PROJ-42'); null when the instance predates it."

addedOutput schema / properties / display_id / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / due_date / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / due_date / default
```
Removed value: -null
```
removedOutput schema / properties / due_date / description
```
Removed value: -"ISO date (YYYY-MM-DD)."
```
addedOutput schema / properties / due_date / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / estimated_hours / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / estimated_hours / default
```
Removed value: -null
```
removedOutput schema / properties / estimated_hours / description
```
Removed value: -"Estimate in hours."
```
addedOutput schema / properties / estimated_hours / type
```
Added value: +[
+  "number",
+  "null"
+]
```

removedOutput schema / properties / id / anyOf

Removed value: -[
-  {
-    "type": "integer"
-  },
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / id / default
```
Removed value: -null
```
removedOutput schema / properties / id / description
```
Removed value: -"Work package id."
```

addedOutput schema / properties / id / type

Added value: +[
+  "integer",
+  "string",
+  "null"
+]

removedOutput schema / properties / lock_version / anyOf

Removed value: -[
-  {
-    "type": "integer"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / lock_version / default
```
Removed value: -null
```

removedOutput schema / properties / lock_version / description

Removed value: -"Optimistic-locking version; pass to update_work_package."

addedOutput schema / properties / lock_version / type
```
Added value: +[
+  "integer",
+  "null"
+]
```
removedOutput schema / properties / notes / default
```
Removed value: -null
```

removedOutput schema / properties / notes / description

Removed value: -"Degradation notes for this result."

changedOutput schema / properties / parent / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / parent / default
```
Removed value: -null
```
removedOutput schema / properties / parent / description
```
Removed value: -"Parent work package."
```

removedOutput schema / properties / percentage_done / anyOf

Removed value: -[
-  {
-    "type": "integer"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / percentage_done / default
```
Removed value: -null
```
removedOutput schema / properties / percentage_done / description
```
Removed value: -"Progress, 0-100."
```
addedOutput schema / properties / percentage_done / type
```
Added value: +[
+  "integer",
+  "null"
+]
```

changedOutput schema / properties / priority / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / priority / default
```
Removed value: -null
```
removedOutput schema / properties / priority / description
```
Removed value: -"Priority."
```

changedOutput schema / properties / project / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / project / default
```
Removed value: -null
```
removedOutput schema / properties / project / description
```
Removed value: -"Owning project."
```

changedOutput schema / properties / project_phase / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / project_phase / default
```
Removed value: -null
```

removedOutput schema / properties / project_phase / description

Removed value: -"Project phase this work package sits in (16.1+, only when phases are active in the project and visible to this user); details via get_project_phase."

removedOutput schema / properties / remaining_hours / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / remaining_hours / default
```
Removed value: -null
```
removedOutput schema / properties / remaining_hours / description
```
Removed value: -"Remaining work in hours."
```
addedOutput schema / properties / remaining_hours / type
```
Added value: +[
+  "number",
+  "null"
+]
```

changedOutput schema / properties / responsible / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / responsible / default
```
Removed value: -null
```
removedOutput schema / properties / responsible / description
```
Removed value: -"Accountable user."
```

removedOutput schema / properties / spent_hours / anyOf

Removed value: -[
-  {
-    "type": "number"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / spent_hours / default
```
Removed value: -null
```
removedOutput schema / properties / spent_hours / description
```
Removed value: -"Logged time in hours."
```
addedOutput schema / properties / spent_hours / type
```
Added value: +[
+  "number",
+  "null"
+]
```

changedOutput schema / properties / sprint / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / sprint / default
```
Removed value: -null
```

removedOutput schema / properties / sprint / description

Removed value: -"The sprint the work package is planned in; null when unassigned."

removedOutput schema / properties / start_date / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / start_date / default
```
Removed value: -null
```
removedOutput schema / properties / start_date / description
```
Removed value: -"ISO date (YYYY-MM-DD)."
```
addedOutput schema / properties / start_date / type
```
Added value: +[
+  "string",
+  "null"
+]
```

changedOutput schema / properties / status / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / status / default
```
Removed value: -null
```
removedOutput schema / properties / status / description
```
Removed value: -"Status."
```

removedOutput schema / properties / story_points / anyOf

Removed value: -[
-  {
-    "type": "integer"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / story_points / default
```
Removed value: -null
```
removedOutput schema / properties / story_points / description
```
Removed value: -"Story points."
```
addedOutput schema / properties / story_points / type
```
Added value: +[
+  "integer",
+  "null"
+]
```

removedOutput schema / properties / subject / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / subject / default
```
Removed value: -null
```
removedOutput schema / properties / subject / description
```
Removed value: -"Subject line."
```
addedOutput schema / properties / subject / type
```
Added value: +[
+  "string",
+  "null"
+]
```

removedOutput schema / properties / target_versions / description

Removed value: -"All target versions; legacy instances yield zero or one."

removedOutput schema / properties / target_versions / items / description

Removed value: -"A reference to another resource. Canonical output shape."

removedOutput schema / properties / target_versions / items / properties / id / anyOf

Removed value: -[
-  {
-    "type": "integer"
-  },
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / target_versions / items / properties / id / default
```
Removed value: -null
```
removedOutput schema / properties / target_versions / items / properties / id / description
```
Removed value: -"Resource id."
```
addedOutput schema / properties / target_versions / items / properties / id / type
```
Added value: +[
+  "integer",
+  "string",
+  "null"
+]
```
removedOutput schema / properties / target_versions / items / properties / name / anyOf
```
Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]
```
removedOutput schema / properties / target_versions / items / properties / name / default
```
Removed value: -null
```
removedOutput schema / properties / target_versions / items / properties / name / description
```
Removed value: -"Human-readable name."
```
addedOutput schema / properties / target_versions / items / properties / name / type
```
Added value: +[
+  "string",
+  "null"
+]
```

changedOutput schema / properties / type / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / type / default
```
Removed value: -null
```
removedOutput schema / properties / type / description
```
Removed value: -"Work package type."
```

removedOutput schema / properties / updated_at / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]

removedOutput schema / properties / updated_at / default
```
Removed value: -null
```
removedOutput schema / properties / updated_at / description
```
Removed value: -"ISO 8601 UTC timestamp."
```
addedOutput schema / properties / updated_at / type
```
Added value: +[
+  "string",
+  "null"
+]
```

changedOutput schema / properties / version / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "description": "A reference to another resource. Canonical output shape.",
-    "properties": {
-      "id": {
-        "anyOf": [
-          {
-            "type": "integer"
-          },
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Resource id."
-      },
-      "name": {
-        "anyOf": [
-          {
-            "type": "string"
-          },
-          {
-            "type": "null"
-          }
-        ],
-        "default": null,
-        "description": "Human-readable name."
-      }
-    },
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": [
+          "integer",
+          "string",
+          "null"
+        ]
+      },
+      "name": {
+        "type": [
+          "string",
+          "null"
+        ]
+      }
+    },
+    "type": "object"
+  },
+  {
+    "type": "null"
+  }
+]

removedOutput schema / properties / version / default
```
Removed value: -null
```

removedOutput schema / properties / version / description

Removed value: -"Legacy alias: the sole target version, or null for zero/multiple."

Changed9 schema fields changedv0.3.3Oct 3, 2026

changedInput schema / properties / assignee / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "type": "integer"
+  },
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / priority / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "type": "integer"
+  },
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / responsible / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "type": "integer"
+  },
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / sprint

Added value: +{
+  "anyOf": [
+    {
+      "type": "integer"
+    },
+    {
+      "type": "string"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": "__unchanged__",
+  "description": "Numeric sprint id from list_sprints; null removes it."
+}

changedInput schema / properties / status / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "type": "integer"
+  },
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / type / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "type": "integer"
+  },
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / version / anyOf

Previous value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "null"
-  }
-]New value: +[
+  {
+    "type": "integer"
+  },
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

changedInput schema / properties / version / description

Previous value: -"Numeric version/sprint id; null removes it."New value: +"Numeric version id; null removes it."

addedOutput schema / properties / sprint

Added value: +{
+  "anyOf": [
+    {
+      "additionalProperties": false,
+      "description": "A reference to another resource. Canonical output shape.",
+      "properties": {
+        "id": {
+          "anyOf": [
+            {
+              "type": "integer"
+            },
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Resource id."
+        },
+        "name": {
+          "anyOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "default": null,
+          "description": "Human-readable name."
+        }
+      },
+      "type": "object"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "The sprint the work package is planned in; null when unassigned."
+}

Changed13 schema fields changedv0.3.2Sep 24, 2026

changedInput schema / properties / assignee / description

Previous value: -"Numeric user id to assign. Omit to leave unchanged; pass null (or 'none') to unassign — that sends a null href rather than a bogus user id."New value: +"Numeric user id; omit to leave unchanged, null (or 'none') to unassign."

changedInput schema / properties / custom_fields / description

Previous value: -"Custom field writes keyed by wire key or display name, e.g. {'Severity': 'High'}. Unknown or non-writable keys fail with the valid keys listed. Only the keys you pass are touched."New value: +"Custom field writes keyed by wire key or display name, e.g. {'Severity': 'High'}. Unknown or non-writable keys fail listing the valid ones. Only passed keys are touched."

changedInput schema / properties / description / description

Previous value: -"New markdown body. Omit to leave unchanged; pass null to empty it. Replaces the whole description — read it with get_work_package first if you mean to append."New value: +"New markdown body; omit to leave unchanged, null to empty it. Replaces the whole text; read it first to append instead."

changedInput schema / properties / estimated_hours / description

Previous value: -"Estimate in hours as a decimal."New value: +"Estimate in hours, decimal."

changedInput schema / properties / id / description

Previous value: -"Work package id to change (the #1234 number)."New value: +"Work package id to change (#1234)."

changedInput schema / properties / lock_version / description

Previous value: -"The `lock_version` you read from get_work_package. Pass it and the write fails loudly (409) if somebody else edited the work package in the meantime. Omit it and the current version is fetched and echoed — still safe, just one more round trip and a slightly wider conflict window."New value: +"The `lock_version` from get_work_package. Passing it makes a concurrent edit fail loudly (409); omitting it fetches and echoes the current version — safe, but a wider conflict window."

changedInput schema / properties / notify / description

Previous value: -"Send OpenProject notification emails for this change."New value: +"Email notifications for this change."

changedInput schema / properties / parent_id / description

Previous value: -"Re-parent this work package under another id; null detaches it and makes it top level. This is the only hierarchy tool — there is no separate set/remove-parent tool."New value: +"Re-parent under another id; null detaches to top level (the only hierarchy tool)."

changedInput schema / properties / remaining_hours / description

Previous value: -"Remaining work in hours as a decimal."New value: +"Remaining work in hours, decimal."

changedInput schema / properties / responsible / description

Previous value: -"Numeric user id of the accountable person; null clears it."New value: +"Numeric id of the accountable person; null clears it."

changedInput schema / properties / status / description

Previous value: -"New status as a name or numeric id. Validated through the form endpoint, so an invalid workflow transition comes back listing the statuses that *are* reachable from the current one."New value: +"New status as a name or id; invalid transitions list the reachable statuses."

changedInput schema / properties / target_versions / description

Previous value: -"Target version ids. [] clears assignments; omit to leave unchanged. Multiple values require instance support. Mutually exclusive with version."New value: +"Target version ids; [] clears, omit leaves unchanged. Multiple values need instance support. Mutually exclusive with version."

changedInput schema / properties / version / description

Previous value: -"Numeric version / sprint id; null removes it from the version."New value: +"Numeric version/sprint id; null removes it."

Changed4 schema fields changedv0.3.1Sep 23, 2026

addedInput schema / properties / remaining_hours

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Remaining work in hours as a decimal."
+}

addedInput schema / properties / story_points

Added value: +{
+  "anyOf": [
+    {
+      "minimum": 0,
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Story points as a non-negative integer."
+}

addedOutput schema / properties / remaining_hours

Added value: +{
+  "anyOf": [
+    {
+      "type": "number"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Remaining work in hours."
+}

addedOutput schema / properties / story_points

Added value: +{
+  "anyOf": [
+    {
+      "type": "integer"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Story points."
+}

Changed3 schema fields changedv0.3.0Sep 14, 2026

addedInput schema / properties / target_versions

Added value: +{
+  "anyOf": [
+    {
+      "items": {
+        "type": "integer"
+      },
+      "type": "array"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Target version ids. [] clears assignments; omit to leave unchanged. Multiple values require instance support. Mutually exclusive with version."
+}

addedOutput schema / properties / target_versions

Added value: +{
+  "description": "All target versions; legacy instances yield zero or one.",
+  "items": {
+    "additionalProperties": false,
+    "description": "A reference to another resource. Canonical output shape.",
+    "properties": {
+      "id": {
+        "anyOf": [
+          {
+            "type": "integer"
+          },
+          {
+            "type": "string"
+          },
+          {
+            "type": "null"
+          }
+        ],
+        "default": null,
+        "description": "Resource id."
+      },
+      "name": {
+        "anyOf": [
+          {
+            "type": "string"
+          },
+          {
+            "type": "null"
+          }
+        ],
+        "default": null,
+        "description": "Human-readable name."
+      }
+    },
+    "type": "object"
+  },
+  "type": "array"
+}

changedOutput schema / properties / version / description

Previous value: -"Version / sprint."New value: +"Legacy alias: the sole target version, or null for zero/multiple."

First observedv0.1.0Aug 12, 2026

TDQS

A4.7/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the annotations, it discloses the optimistic locking contract, the meaning of a 409 conflict, the returned lock_version, and the omitted-vs-null pitfall. This gives the agent the context needed to handle concurrency and clearing safely.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is front-loaded with purpose, then usage, return behavior, pitfalls, and ID sources. It is appropriately detailed for a 22-parameter mutation tool and does not waste sentences.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a complex update tool with an output schema, it covers the important behavior an agent needs: locking, conflict handling, field clearing, return shape, and parameter sourcing. Nothing critical is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3. The description adds value by aggregating the omitted-versus-null semantics, explaining lock_version behavior, and naming the sibling tools that supply valid IDs and field values.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource: change any writable field of a work package. It also distinguishes this multi-field update tool from narrower operations by listing assign/unassign, status, scheduling, re-parenting, progress, and custom fields.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives clear usage examples and ID/value sources for parameters. It does not explicitly mention when to prefer the sibling bulk_update_work_packages tool, so it stops short of full when/when-not guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server