crewAIInc/crewAI · error · SystemExit

Missing required input '{name}'{suffix}

Error message

Missing required input '{name}'{suffix}

What it means

Input validation for declarative flows: after merging defaults (from the definition) with interactively collected or passed inputs, _missing_required() found required state fields still absent. Each missing field is printed in red, with the field's schema `description` appended as a hint when present, then the CLI exits 1 before the flow starts.

Source

Thrown at lib/cli/src/crewai_cli/run_declarative_flow.py:322

        collected.update(
            prompt_for_inputs(
                missing,
                title="Flow inputs",
                subtitle="This flow needs the following to run.",
                describe=lambda name: (properties.get(name) or {}).get("description"),
                coerce=lambda name, raw: _coerce_input(raw, properties.get(name) or {}),
            )
        )
        missing = _missing_required(state_model, {**defaults, **collected})

    if missing:
        for name in missing:
            description = (properties.get(name) or {}).get("description")
            suffix = f" — {description}" if description else ""
            click.secho(
                f"  Missing required input '{name}'{suffix}", fg="red", err=True
            )
        raise SystemExit(1)

    _validate_flow_inputs(state_model, {**defaults, **collected})
    return collected


def _is_interactive() -> bool:
    """Prompt only in an interactive terminal, never in non-interactive mode."""
    return is_interactive()


def _flow_state_schema(flow: Any) -> dict[str, Any] | None:
    """Return the flow's state JSON schema, or ``None`` for dict/plain state."""
    state = getattr(flow, "state", None)
    if state is None or isinstance(state, dict):
        return None
    model_json_schema = getattr(type(state), "model_json_schema", None)
    if not callable(model_json_schema):
        return None

View on GitHub (pinned to 754d7323be)

Solutions

1. Supply each listed field via the flow's inputs mechanism (command flags or inputs file) with the exact field name.
2. In interactive mode, answer the prompts for those fields instead of skipping them.
3. If a field should be optional, give it a default value in the flow's state model (pydantic default or default_factory).
4. Check the appended description in the error line for the expected format/meaning of the field.

Example fix

# before
# state: class FlowState(BaseModel): topic: str  # required
$ crewai flow run  # non-interactive, no topic given
#   Missing required input 'topic' — The research topic

# after
$ crewai flow run --inputs '{"topic": "quantum computing"}'

# or make it optional in the state model:
class FlowState(BaseModel):
    topic: str = "general"

from crewai_cli.run_declarative_flow import _missing_required

schema = _flow_state_schema(flow)  # or build the state model directly
required = {k for k, v in (schema or {}).get("properties", {}).items()
            if k in (schema or {}).get("required", [])}
provided = {**defaults, **collected}
missing = required - provided.keys()
if missing:
    raise SystemExit(f"missing required flow inputs: {sorted(missing)}")

When it happens

Trigger: Running a declarative flow whose state model has required fields (no default) that are not covered by: --inputs values, prompted answers in interactive mode, or defaults declared in the definition. Required fields with `default_factory` or defaults are never reported.

Common situations: Team shares a flow definition whose state model gained new required fields; non-interactive runs skipping prompts so required inputs are silently absent; typos in input keys versus state field names.

Related errors

• Invalid input '{location}': {error.get('msg')}
• Unable to read --definition path {definition_path}: {exc}
• Invalid --inputs JSON: {exc}
• Invalid --inputs JSON: expected an object.
• Missing required input '{name}'

AI-assisted analysis of crewAIInc/crewAI@754d7323be (2026-08-15). Data as JSON: /api/errors/6728aaf2fa6aac9c. Report an issue: GitHub.