calesthio/OpenMontage · error · ValueError

duration_seconds is required for cost estimation

Error message

duration_seconds is required for cost estimation

What it means

Raised by fal_elevenlabs_music.estimate_cost when inputs has no duration_seconds. Because fal bills per output minute ($0.80/min rounded up), cost cannot be computed without a duration; the tool deliberately refuses to guess instead of defaulting silently.

Source

Thrown at tools/audio/fal_elevenlabs_music.py:131

        "Listen to the generated music for mood, mix, and duration",
    ]

    _MODEL = "fal-ai/elevenlabs/music"
    _QUEUE_URL = f"https://queue.fal.run/{_MODEL}"
    _POLL_INTERVAL_SECONDS = 5
    _MAX_WAIT_SECONDS = 600

    def _get_api_key(self) -> str | None:
        return os.environ.get("FAL_KEY") or os.environ.get("FAL_AI_API_KEY")

    def get_status(self) -> ToolStatus:
        return ToolStatus.AVAILABLE if self._get_api_key() else ToolStatus.UNAVAILABLE

    def estimate_cost(self, inputs: dict[str, Any]) -> float:
        """fal bills $0.80 per output minute, rounded up to a full minute."""
        duration = inputs.get("duration_seconds")
        if duration is None:
            raise ValueError("duration_seconds is required for cost estimation")
        return round(math.ceil(float(duration) / 60.0) * 0.80, 2)

    def execute(self, inputs: dict[str, Any]) -> ToolResult:
        api_key = self._get_api_key()
        if not api_key:
            return ToolResult(
                success=False,
                error="No fal.ai API key found. " + self.install_instructions,
            )

        duration = inputs.get("duration_seconds")
        if duration is None:
            return ToolResult(success=False, error="duration_seconds is required")
        duration = float(duration)
        if not 3 <= duration <= 600:
            return ToolResult(
                success=False,
                error="duration_seconds must be between 3 and 600",

View on GitHub (pinned to 95e1c3d0ab)

Solutions

1. Pass duration_seconds (number of seconds) in inputs before any cost estimation
2. Derive it from the approved target runtime in the script/proposal rather than a constant
3. Add a schema/validation check upstream that rejects inputs without duration_seconds early

Example fix

// before
inputs = {"prompt": "upbeat jingle"}
cost = tool.estimate_cost(inputs)  # raises

// after
inputs = {"prompt": "upbeat jingle", "duration_seconds": 30}
cost = tool.estimate_cost(inputs)

if "duration_seconds" not in inputs or inputs["duration_seconds"] is None:
    raise ValueError("duration_seconds required before estimating fal music cost")

When it happens

Trigger: Calling estimate_cost (directly or via a cost-checking planner) with inputs lacking duration_seconds; execute() later enforces the same requirement.

Common situations: A pipeline/orchestrator calls estimate_cost before assembling full inputs; dict key typo (duration, length) instead of duration_seconds; porting code from a tool that defaulted the duration.

Related errors

• music_gen.estimate_cost: duration_seconds is required. Deriv
• model_id must be one of: {choices}
• ${res.status} ${url}
• fetch failed ${r.status}: ${url}
• path escapes project

AI-assisted analysis of calesthio/OpenMontage@95e1c3d0ab (2026-08-15). Data as JSON: /api/errors/ce7ef28ce156ec73. Report an issue: GitHub.