OpenProject MCP Server

Instructions

Args:
    from_id: Source work package ID
    to_id: Target work package ID
    relation_type: Type of relation (relates, duplicates, blocks, precedes, follows, includes, partof, requires)
    lag: Optional lag in days for precedes/follows relations

Implementation Reference

• src/openproject_mcp/tools/relations.py:42-87 (handler)

  Core implementation of the create_relation tool, handling API call to create relation between work packages.

  async def create_relation(
      from_id: int,
      to_id: int,
      relation_type: RelationType,
      lag: int | None = None,
  ) -> dict[str, Any]:
      """Create a relation between two work packages.
  
      Args:
          from_id: Source work package ID
          to_id: Target work package ID
          relation_type: Type of relation. Options:
              - relates: General relation
              - duplicates: Source duplicates target
              - duplicated: Source is duplicated by target
              - blocks: Source blocks target
              - blocked: Source is blocked by target
              - precedes: Source precedes target (with optional lag in days)
              - follows: Source follows target (with optional lag in days)
              - includes: Source includes target (parent-child)
              - partof: Source is part of target (child-parent)
              - requires: Source requires target
              - required: Source is required by target
          lag: Optional lag in days for precedes/follows relations
  
      Returns:
          Created relation object
      """
      client = OpenProjectClient()
  
      try:
          payload: dict[str, Any] = {
              "_links": {
                  "from": build_link(f"/api/v3/work_packages/{from_id}"),
                  "to": build_link(f"/api/v3/work_packages/{to_id}"),
              },
              "type": relation_type,
          }
  
          if lag is not None:
              payload["lag"] = lag
  
          result = await client.post("relations", data=payload)
          return result
      finally:
          await client.close()

• src/openproject_mcp/server.py:331-351 (registration)

  MCP tool registration for create_relation, which delegates to the relations module implementation.

  @mcp.tool()
  async def create_relation(
      from_id: int,
      to_id: int,
      relation_type: str,
      lag: int | None = None,
  ):
      """Create a relation between two work packages.
  
      Args:
          from_id: Source work package ID
          to_id: Target work package ID
          relation_type: Type of relation (relates, duplicates, blocks, precedes, follows, includes, partof, requires)
          lag: Optional lag in days for precedes/follows relations
      """
      return await relations.create_relation(
          from_id=from_id,
          to_id=to_id,
          relation_type=relation_type,  # type: ignore
          lag=lag,
      )

• src/openproject_mcp/tools/relations.py:9-21 (schema)

  Type definition for valid relation_type values used in create_relation.

  RelationType = Literal[
      "relates",
      "duplicates",
      "duplicated",
      "blocks",
      "blocked",
      "precedes",
      "follows",
      "includes",
      "partof",
      "requires",
      "required",
  ]