BerriAI/litellm · error · HTTPException

Agent with name {request.get('agent_name')} already exists

Error message

Agent with name {request.get('agent_name')} already exists

What it means

Agent creation checks the in-memory registry for a name conflict before inserting; duplicate agent_name would create ambiguous lookups (by-name resolution), so the create is rejected with the conflicting name.

Source

Thrown at litellm/proxy/agent_endpoints/endpoints.py:421

    ```
    """
    await check_feature_access_for_user(user_api_key_dict, "agents")

    from litellm.proxy.proxy_server import prisma_client

    _check_agent_management_permission(user_api_key_dict)

    if prisma_client is None:
        raise HTTPException(status_code=500, detail="Prisma client not initialized")

    try:
        # Get the user ID from the API key auth
        created_by: Final = user_api_key_dict.user_id or "unknown"

        # check for naming conflicts
        existing_agent: Final = AGENT_REGISTRY.get_agent_by_name(agent_name=request.get("agent_name"))
        if existing_agent is not None:
            raise HTTPException(
                status_code=400,
                detail=f"Agent with name {request.get('agent_name')} already exists",
            )

        # Apply the LiteLLM-fronting merge only when the admin actually
        # provided an agent card. Plain chat/LLM agents register without
        # ``agent_card_params``, and synthesising a default A2A card for them
        # would advertise capabilities (``supportedInterfaces``, security
        # schemes, default skills) the agent doesn't actually expose.
        upstream_card: Final = request.get("agent_card_params")
        agent_to_create: AgentConfig = request
        new_agent_id: str | None = None
        if upstream_card is not None:
            # Pre-generate the agent_id so the merged card can reference it
            # in ``supportedInterfaces`` before the DB row exists.
            new_agent_id = str(uuid.uuid4())
            merged_card: Final = _build_merged_agent_card(
                upstream_card,

View on GitHub (pinned to 77b7c6c40c)

Solutions

1. Choose a different agent_name; names must be unique.

Example fix

agent_name='my-agent-2'

When it happens

Trigger: Thrown at litellm/proxy/agent_endpoints/endpoints.py:421 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of BerriAI/litellm@77b7c6c40c (2026-08-18). Data as JSON: /api/errors/a86f574baf6be7e8. Report an issue: GitHub.