sgl-project/sglang · error · ValueError

Unknown action domain name {domain_name!r}. Valid names: {so

Error message

Unknown action domain name {domain_name!r}. Valid names: {sorted(EMBODIMENT_TO_DOMAIN_ID)}

What it means

When domain_name is given instead of domain_id, it is normalized (strip+lower) and looked up in the EMBODIMENT_TO_DOMAIN_ID registry. Unknown names are rejected with the list of valid names to prevent silent domain mismatches.

Source

Thrown at python/sglang/multimodal_gen/runtime/pipelines_core/stages/model_specific_stages/cosmos3.py:641

    def component_uses(
        self, server_args: ServerArgs, stage_name: str | None = None
    ) -> list[ComponentUse]:
        return [ComponentUse(self._component_stage_name(stage_name), "vae")]

    @staticmethod
    def _resolve_domain_id(batch: Req) -> int:
        """Resolve action embodiment domain ID; required for action generation."""
        domain_id = getattr(batch.sampling_params, "domain_id", None)
        if domain_id is not None:
            domain_id = int(domain_id)
            if domain_id < 0:
                raise ValueError(f"domain_id must be non-negative, got {domain_id}")
            return domain_id
        domain_name = getattr(batch.sampling_params, "domain_name", None)
        if domain_name:
            key = str(domain_name).strip().lower()
            if key not in EMBODIMENT_TO_DOMAIN_ID:
                raise ValueError(
                    f"Unknown action domain name {domain_name!r}. "
                    f"Valid names: {sorted(EMBODIMENT_TO_DOMAIN_ID)}"
                )
            return EMBODIMENT_TO_DOMAIN_ID[key]
        raise ValueError(
            "Cosmos3 action generation requires --domain-id or --domain-name."
        )

    def _prepare_action_latents(
        self,
        batch: Req,
        generator,
        device: torch.device,
        dtype: torch.dtype,
    ) -> None:
        """Prepare action latents and conditioning, writing them onto ``batch``.

        Action tokens run at frame rate (no temporal compression), so the chunk

View on GitHub (pinned to 0132848349)

Solutions

1. Use one of the valid names printed in the error (lowercase, exact spelling)
2. Check casing/underscores: the lookup strips and lowercases but does not fuzzy match
3. Fall back to the numeric domain_id if the name is unlisted

Example fix

# before
sp.domain_name = 'Franka Arm'

# after
sp.domain_name = 'franka_arm'  # exact key from EMBODIMENT_TO_DOMAIN_ID

from sglang.multimodal_gen... import EMBODIMENT_TO_DOMAIN_ID
key = sp.domain_name.strip().lower()
assert key in EMBODIMENT_TO_DOMAIN_ID, f'use one of {sorted(EMBODIMENT_TO_DOMAIN_ID)}'

def known_domain_name(name: str, registry: dict) -> bool:
    return name.strip().lower() in registry

try:
    stage.forward(batch)
except ValueError as e:
    if 'Unknown action domain name' in str(e):
        sp.domain_name = 'franka_arm'  # fallback to a known domain
    else:
        raise

When it happens

Trigger: Passing sampling_params.domain_name not present in EMBODIMENT_TO_DOMAIN_ID (e.g. 'Franka-ARM' if 'franka_arm' is the registered key, or a typo).

Common situations: Guessing embodiment names, casing/separator mismatches, or a new robot not yet in the registry.

Related errors

• action_mode is set but the loaded Cosmos3 checkpoint has no
• domain_id must be non-negative, got {domain_id}
• action must have shape [T, D], got {tuple(action.shape)}
• No raw action dim for Cosmos3 embodiment {embodiment!r}. Exp
• Cosmos3 action input accepts one image field; use a list or

AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/e66c64167a308a43. Report an issue: GitHub.