OpenBB-finance/OpenBB · error · ValueError

Prompt name cannot be empty string

Error message

Prompt name cannot be empty string

What it means

Pydantic validation error on PromptConfigModel.name: an explicit name was provided but it is only whitespace (e.g. " "). Names are optional (auto-generated when None), but if present they must be non-empty; a whitespace-only string is treated as a mistake rather than a name.

Source

Thrown at openbb_platform/extensions/mcp_server/openbb_mcp_server/models/mcp_config.py:124

            raise ValueError("Prompt content cannot be empty")

        # Check for unmatched braces
        open_braces = v.count("{")
        close_braces = v.count("}")
        if open_braces != close_braces:
            raise ValueError(
                f"Unmatched braces in prompt content: {open_braces} opening, {close_braces} closing"
            )

        return v

    @field_validator("name")
    @classmethod
    def validate_name(cls, v: str | None) -> str | None:
        """Validate prompt name if provided."""
        if v is not None:
            if not v.strip():
                raise ValueError("Prompt name cannot be empty string")
            # Check for valid identifier-like name
            if not re.match(r"^[a-zA-Z_][a-zA-Z0-9_]*$", v.strip()):
                raise ValueError(f"Prompt name '{v}' should be a valid identifier")
        return v

    @field_validator("tags")
    @classmethod
    def validate_tags(cls, v: list[str]) -> list[str]:
        """Validate tags are non-empty strings."""
        validated_tags = []
        for tag in v:
            if not isinstance(tag, str):
                raise ValueError(f"Tag must be a string, got {type(tag)}")
            if not tag.strip():
                raise ValueError("Tag cannot be empty string")
            validated_tags.append(tag.strip())
        return validated_tags

View on GitHub (pinned to 3e071fcc2c)

Solutions

1. Either delete the name key entirely (it will be auto-generated) or supply a real name.
2. Trim whitespace from name values in the config.
3. In generators, emit no name key when the computed name is blank.

Example fix

# before
prompts:
  - name: "   "
    content: "Hello"

# after
prompts:
  - content: "Hello"  # name omitted -> auto-generated
# or
prompts:
  - name: hello
    content: "Hello"

def clean_prompt_name(name: str | None) -> str | None:
    if name is None:
        return None
    name = name.strip()
    return name or None  # whitespace-only -> omit and let server auto-generate

def is_usable_prompt_name(name: str | None) -> bool:
    return name is None or bool(name.strip())

When it happens

Trigger: Config entries with name: "" or name: " " after YAML/JSON editing; template systems emitting a whitespace placeholder when no name is set; trailing-space typos.

Common situations: Removing a name but leaving spaces in the config; generated configs where an f-string name renders to whitespace.

Related errors

• Prompt name '{v}' should be a valid identifier
• Argument name '{v}' must be a valid Python identifier
• Prompt content cannot be empty
• Unmatched braces in prompt content: {open_braces} opening, {
• Argument name cannot be empty

AI-assisted analysis of OpenBB-finance/OpenBB@3e071fcc2c (2026-08-14). Data as JSON: /api/errors/23dc7a3f16939db2. Report an issue: GitHub.