fix: only treat interpolatable placeholders as crew inputs

lib/crewai/src/crewai/crew.py

@@ -7,7 +7,6 @@ from copy import copy as shallow_copy
 from hashlib import md5
 import json
 from pathlib import Path
-import re
 from typing import (
     TYPE_CHECKING,
     Annotated,
@@ -142,7 +141,10 @@ from crewai.utilities.streaming import (
     signal_end,
     signal_error,
 )
-from crewai.utilities.string_utils import sanitize_tool_name
+from crewai.utilities.string_utils import (
+    extract_template_variables,
+    sanitize_tool_name,
+)
 from crewai.utilities.task_output_storage_handler import TaskOutputStorageHandler
 from crewai.utilities.training_handler import CrewTrainingHandler
 
@@ -1960,20 +1962,24 @@ class Crew(FlowTrackable, BaseModel):
         Scans each task's 'description' + 'expected_output', and each agent's
         'role', 'goal', and 'backstory'.
 
+        Only placeholders that interpolation can actually fill are returned;
+        non-identifier expressions such as ``{x if x else "y"}`` are ignored so
+        they are not surfaced as required inputs (matching interpolation
+        behavior, see :func:`extract_template_variables`).
+
         Returns a set of all discovered placeholder names.
         """
-        placeholder_pattern = re.compile(r"\{(.+?)}")
         required_inputs: set[str] = set()
 
         for task in self.tasks:
             # description and expected_output might contain e.g. {topic}, {user_name}
             text = f"{task.description or ''} {task.expected_output or ''}"
-            required_inputs.update(placeholder_pattern.findall(text))
+            required_inputs.update(extract_template_variables(text))
 
         for agent in self.agents:
             # role, goal, backstory might have placeholders like {role_detail}, etc.
             text = f"{agent.role or ''} {agent.goal or ''} {agent.backstory or ''}"
-            required_inputs.update(placeholder_pattern.findall(text))
+            required_inputs.update(extract_template_variables(text))
 
         return required_inputs
 

lib/crewai/src/crewai/utilities/string_utils.py

@@ -23,6 +23,26 @@ def _duplicate_separator_pattern(separator: str) -> re.Pattern[str]:
     return re.compile(f"(?:{re.escape(separator)}){{2,}}")
 
 
+def extract_template_variables(input_string: str | None) -> list[str]:
+    """Return the template variable names referenced in a string.
+
+    Only recognizes placeholders that interpolation can actually fill, i.e.
+    ``{name}`` where ``name`` starts with a letter/underscore and contains only
+    letters, numbers, underscores, and hyphens. Expressions such as
+    ``{x if x else "y"}`` or JSON snippets are intentionally ignored so they are
+    never treated as required inputs.
+
+    Args:
+        input_string: The string to scan. May be ``None`` or empty.
+
+    Returns:
+        The matched variable names, in order of appearance (with duplicates).
+    """
+    if not input_string:
+        return []
+    return _VARIABLE_PATTERN.findall(input_string)
+
+
 def sanitize_tool_name(name: str, max_length: int = _MAX_TOOL_NAME_LENGTH) -> str:
     """Sanitize tool name for LLM provider compatibility.
 

lib/crewai/tests/test_crew.py

@@ -3895,6 +3895,29 @@ def test_fetch_inputs():
     )
 
 
+def test_fetch_inputs_ignores_non_identifier_placeholders():
+    agent = Agent(
+        role="Report writer",
+        goal="Write a report for {company_name}.",
+        backstory="Expert reporter.",
+    )
+
+    task = Task(
+        description=(
+            'Greet {company_name if company_name else "Individual Client"} '
+            "and summarize {search_period}."
+        ),
+        expected_output="A summary for {company_name}.",
+        agent=agent,
+    )
+
+    crew = Crew(agents=[agent], tasks=[task])
+
+    # Only the simple {company_name} placeholders are returned; the inline conditional
+    # expression (which interpolation cannot fill) is ignored.
+    assert crew.fetch_inputs() == {"company_name", "search_period"}
+
+
 @pytest.mark.vcr()
 def test_task_tools_preserve_code_execution_tools():
     """

lib/crewai/tests/utilities/test_string_utils.py

@@ -1,7 +1,45 @@
 from typing import Any, Dict, List, Union
 
 import pytest
-from crewai.utilities.string_utils import interpolate_only
+from crewai.utilities.string_utils import (
+    extract_template_variables,
+    interpolate_only,
+)
+
+
+class TestExtractTemplateVariables:
+    """Tests for extract_template_variables in string_utils.py."""
+
+    def test_extracts_simple_identifiers(self):
+        assert extract_template_variables("Hi {name}, see {topic}.") == [
+            "name",
+            "topic",
+        ]
+
+    def test_allows_underscores_and_hyphens(self):
+        assert extract_template_variables("{user_name} {role-detail}") == [
+            "user_name",
+            "role-detail",
+        ]
+
+    def test_ignores_inline_expressions(self):
+        text = '{company_name if company_name else "Individual Client"}'
+        assert extract_template_variables(text) == []
+
+    def test_ignores_json_like_braces(self):
+        assert extract_template_variables('{"key": "value"}') == []
+
+    def test_matches_what_interpolation_fills(self):
+        text = 'Use {topic} and {x if x else "y"}.'
+        variables = extract_template_variables(text)
+        assert variables == ["topic"]
+        # interpolation fills exactly the extracted variable and leaves the rest
+        result = interpolate_only(text, {"topic": "AI"})
+        assert result == 'Use AI and {x if x else "y"}.'
+
+    @pytest.mark.parametrize("value", [None, ""])
+    def test_handles_empty_input(self, value):
+        assert extract_template_variables(value) == []
 
 
 class TestInterpolateOnly: