Get branch merge preview

{
  "type": "object",
  "properties": {
    "target_branch_id": {
      "anyOf": [
        {
          "type": "string",
          "format": "uuid",
          "description": "Provide the target branch id."
        },
        {
          "type": "null",
          "description": "Provide the target branch id."
        }
      ],
      "description": "Target branch ID; omit for main."
    },
    "branch_id": {
      "type": "string",
      "format": "uuid",
      "description": "Branch to merge. A missing branch and one you cannot read are both not found."
    }
  },
  "required": [
    "branch_id"
  ],
  "additionalProperties": false,
  "description": "Use this before merge_branch to review the file-by-file changes a merge applies and to resolve conflicts. Returns the source branch, the target, can_merge with blocked_reason, has_conflicts, and one diff per changed file with its conflict regions and the content of each side.",
  "$schema": "http://json-schema.org/draft-07/schema#"
}

{
  "type": "object",
  "properties": {
    "source_branch": {
      "type": "object",
      "properties": {
        "id": {
          "type": "string",
          "format": "uuid",
          "description": "Branch ID."
        },
        "name": {
          "type": "string",
          "description": "Branch name, unique in the project."
        },
        "project_id": {
          "type": "string",
          "format": "uuid",
          "description": "Project that owns the branch."
        },
        "base_branch_id": {
          "anyOf": [
            {
              "type": "string",
              "format": "uuid"
            },
            {
              "type": "null",
              "description": "The base branch id returned by the tool."
            }
          ],
          "description": "Branch this branch was created from, or null for the root branch."
        },
        "status": {
          "type": "string",
          "enum": [
            "active",
            "merged",
            "closed"
          ],
          "description": "Lifecycle state; closed is distinct from merged."
        },
        "description": {
          "type": [
            "string",
            "null"
          ],
          "description": "Branch description, or null."
        },
        "auto_delete_on_merge": {
          "type": "boolean",
          "description": "Whether the branch is deleted after it merges."
        },
        "version": {
          "type": "integer",
          "minimum": 0,
          "description": "Version to pass as expected_version when merging."
        },
        "created_at": {
          "type": "string",
          "description": "Creation time."
        },
        "created_by": {
          "anyOf": [
            {
              "$ref": "#/properties/source_branch/properties/base_branch_id/anyOf/0",
              "description": "The created by returned by the tool."
            },
            {
              "type": "null",
              "description": "The created by returned by the tool."
            }
          ],
          "description": "User who created the branch, or null."
        },
        "updated_at": {
          "type": [
            "string",
            "null"
          ],
          "description": "Last update time, or null."
        },
        "merged_at": {
          "type": [
            "string",
            "null"
          ],
          "description": "Merge time, or null before a merge."
        },
        "merged_by": {
          "anyOf": [
            {
              "$ref": "#/properties/source_branch/properties/base_branch_id/anyOf/0",
              "description": "The merged by returned by the tool."
            },
            {
              "type": "null",
              "description": "The merged by returned by the tool."
            }
          ],
          "description": "User who merged the branch, or null."
        }
      },
      "required": [
        "id",
        "name",
        "project_id",
        "base_branch_id",
        "status",
        "description",
        "auto_delete_on_merge",
        "version",
        "created_at",
        "created_by",
        "updated_at",
        "merged_at",
        "merged_by"
      ],
      "additionalProperties": false,
      "description": "Branch to merge."
    },
    "target_branch_id": {
      "anyOf": [
        {
          "$ref": "#/properties/source_branch/properties/base_branch_id/anyOf/0",
          "description": "The target branch id returned by the tool."
        },
        {
          "type": "null",
          "description": "The target branch id returned by the tool."
        }
      ],
      "description": "Branch that receives the merge, or null for main."
    },
    "target_branch_name": {
      "type": "string",
      "description": "Name of the branch that receives the merge."
    },
    "can_merge": {
      "type": "boolean",
      "description": "True only when blocked_reason is null, merge policies pass and no file has conflicts. Advisory: the merge checks these conditions again."
    },
    "blocked_reason": {
      "type": [
        "string",
        "null"
      ],
      "description": "Precondition that blocks the merge, such as a merged or closed branch, or a target that is the source branch or is closed; null when none does. A target that is missing or in another project is a not found error."
    },
    "has_conflicts": {
      "type": "boolean",
      "description": "Whether at least one file has conflicts."
    },
    "diffs": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "file_path": {
            "type": "string",
            "description": "File path; the file ID when neither side has a path."
          },
          "file_type": {
            "type": "string",
            "description": "File type."
          },
          "file_id": {
            "type": [
              "string",
              "null"
            ],
            "description": "File ID, or null."
          },
          "has_conflicts": {
            "type": "boolean",
            "description": "Whether the file has conflicts that block an automatic merge."
          },
          "conflict_count": {
            "type": "integer",
            "minimum": 0,
            "description": "Number of conflict regions."
          },
          "conflict_regions": {
            "type": "array",
            "items": {
              "type": "object",
              "properties": {
                "id": {
                  "type": "string",
                  "description": "Region ID, stable within one preview; conflict resolutions are keyed by it."
                },
                "type": {
                  "type": "string",
                  "const": "conflict",
                  "description": "Region kind."
                },
                "base_start": {
                  "type": "integer",
                  "description": "First line in the common base."
                },
                "base_end": {
                  "type": "integer",
                  "description": "Last line in the common base."
                },
                "target_start": {
                  "type": "integer",
                  "description": "First line in the target branch."
                },
                "target_end": {
                  "type": "integer",
                  "description": "Last line in the target branch."
                },
                "source_start": {
                  "type": "integer",
                  "description": "First line in the source branch."
                },
                "source_end": {
                  "type": "integer",
                  "description": "Last line in the source branch."
                },
                "base_lines": {
                  "type": "string",
                  "description": "Conflicting text in the common base."
                },
                "target_lines": {
                  "type": "string",
                  "description": "Conflicting text in the target branch."
                },
                "source_lines": {
                  "type": "string",
                  "description": "Conflicting text in the source branch."
                }
              },
              "required": [
                "id",
                "type",
                "base_start",
                "base_end",
                "target_start",
                "target_end",
                "source_start",
                "source_end",
                "base_lines",
                "target_lines",
                "source_lines"
              ],
              "additionalProperties": false
            },
            "description": "Conflicting line ranges."
          },
          "is_new": {
            "type": "boolean",
            "description": "The merge adds the file to the target."
          },
          "is_deleted": {
            "type": "boolean",
            "description": "The merge deletes the file from the target."
          },
          "is_modified": {
            "type": "boolean",
            "description": "The merge changes the file in the target."
          },
          "base_changed": {
            "type": "boolean",
            "description": "The target changed the file since the branch was created."
          },
          "branch_changed": {
            "type": "boolean",
            "description": "The branch changed the file."
          },
          "base_content": {
            "type": [
              "string",
              "null"
            ],
            "description": "Content at the common base, or null."
          },
          "target_content": {
            "type": [
              "string",
              "null"
            ],
            "description": "Content in the target branch, or null."
          },
          "source_content": {
            "type": [
              "string",
              "null"
            ],
            "description": "Content in the source branch, or null."
          }
        },
        "required": [
          "file_path",
          "file_type",
          "file_id",
          "has_conflicts",
          "conflict_count",
          "conflict_regions",
          "is_new",
          "is_deleted",
          "is_modified",
          "base_changed",
          "branch_changed",
          "base_content",
          "target_content",
          "source_content"
        ],
        "additionalProperties": false
      },
      "description": "File-by-file changes the merge applies."
    }
  },
  "required": [
    "source_branch",
    "target_branch_id",
    "target_branch_name",
    "can_merge",
    "blocked_reason",
    "has_conflicts",
    "diffs"
  ],
  "additionalProperties": false,
  "description": "Structured result returned by the get_branch_merge_preview tool.",
  "$schema": "http://json-schema.org/draft-07/schema#"
}