# Create tag

Create a new tag for the project. Tags are used to categorize budget line items
and enable advanced filtering capabilities.

Note: Tag names cannot be changed after creation. Only the color can be updated.


Endpoint: POST /projects/{projectId}/tags
Version: 1.0.0
Security: ApiKeyAuth

## Path parameters:

  - `projectId` (string, required)
    Project identifier (alias or ID)
    Example: "nike-spring-2024"

## Request fields (application/json):

  - `name` (string, required)
    Tag name (must be unique within project)
    Example: "Post-Production"

  - `color` (string)
    Optional hex color code for visual identification
    Example: "#3B82F6"

  - `description` (string)
    Optional description for documentation purposes
    Example: "Post-production and VFX expenses"

## Response 201 fields (application/json):

  - `id` (string, required)
    Unique tag identifier (same as tag name)
    Example: "Post-Production"

  - `name` (string, required)
    Tag name (1-100 characters, immutable after creation)
    Example: "Post-Production"

  - `color` (string)
    Optional hex color code for visual identification
    Example: "#3B82F6"

  - `description` (string)
    Optional description for documentation purposes
    Example: "Post-production and VFX expenses"

  - `totals` (object, required)
    Financial totals aggregated from all budget line items assigned to this tag

  - `totals.phaseTotals` (object, required)
    Total amounts by phase ID. Keys depend on idMode parameter:
- idMode=user: phase aliases (e.g., "estimate", "actual")
- idMode=system: internal database IDs (UUID strings)
    Example: {"estimate":15000,"actual":12500}

  - `totals.fringeTotals` (object, required)
    Fringe benefit totals by phase ID. Keys follow same format as phaseTotals.
    Example: {"estimate":2250,"actual":1875}

  - `totals.actualTotal` (number, required)
    Total actual expenses for this tag across all phases
    Example: 14375

## Response 400 fields (application/json):

  - `error` (string, required)
    Error message
    Example: "Invalid request parameters"

  - `details` (object)
    Additional error details
    Example: {"field":"projectId","reason":"Project not found"}

  - `code` (string)
    Error code
    Example: "VALIDATION_ERROR"

## Response 401 fields (application/json):

  - `error` (string, required)
    Error message
    Example: "Invalid request parameters"

  - `details` (object)
    Additional error details
    Example: {"field":"projectId","reason":"Project not found"}

  - `code` (string)
    Error code
    Example: "VALIDATION_ERROR"

## Response 409 fields (application/json):

  - `error` (string, required)
    Error message
    Example: "Invalid request parameters"

  - `details` (object)
    Additional error details
    Example: {"field":"projectId","reason":"Project not found"}

  - `code` (string)
    Error code
    Example: "VALIDATION_ERROR"

## Response 500 fields (application/json):

  - `error` (string, required)
    Error message
    Example: "Invalid request parameters"

  - `details` (object)
    Additional error details
    Example: {"field":"projectId","reason":"Project not found"}

  - `code` (string)
    Error code
    Example: "VALIDATION_ERROR"