diff --git a/templates/commands/tasks.md b/templates/commands/tasks.md
index 64146a35aa..99e276fa7a 100644
--- a/templates/commands/tasks.md
+++ b/templates/commands/tasks.md
@@ -197,6 +197,7 @@ Every task MUST strictly follow this format:
    - Map each entity to the user story(ies) that need it
    - If entity serves multiple stories: Put in earliest story or Setup phase
    - Relationships → service layer tasks in appropriate story phase
+   - For each field with constraints in data-model.md (max length, nullable/required, enum values, validation rules), quote the constraint verbatim in the task description so it is not left to implementation-time discretion
 
 4. **From Setup/Infrastructure**:
    - Shared infrastructure → Setup phase (Phase 1)
diff --git a/tests/test_tasks_template_constraints.py b/tests/test_tasks_template_constraints.py
new file mode 100644
index 0000000000..a76cfb050b
--- /dev/null
+++ b/tests/test_tasks_template_constraints.py
@@ -0,0 +1,29 @@
+"""Regression test for #4383: tasks.md loses data-model field constraints.
+
+The /speckit.tasks command template maps data-model.md entities to task
+descriptions but did not require that field-level constraints (max length,
+nullable/required, enum values, validation rules) be carried into the
+generated task text verbatim. Without an explicit instruction, the
+implementing agent falls back to its own defaults instead of the value
+recorded in data-model.md.
+"""
+
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).parent.parent
+TASKS_TEMPLATE = REPO_ROOT / "templates" / "commands" / "tasks.md"
+
+
+def test_data_model_section_requires_verbatim_field_constraints():
+    content = TASKS_TEMPLATE.read_text(encoding="utf-8")
+
+    from_data_model_start = content.index("**From Data Model**")
+    next_section_start = content.index("**From Setup/Infrastructure**")
+    section = content[from_data_model_start:next_section_start]
+
+    assert "quote the constraint verbatim in the task description" in section.lower(), (
+        "The 'From Data Model' task-organization rules must instruct the "
+        "agent to quote field constraints (max length, nullable, enum, "
+        "validation rules) from data-model.md verbatim in task descriptions, "
+        "not merely mention that constraints exist."
+    )