p-e-w/heretic · error · ValueError

whitespace is not allowed

Error message

whitespace is not allowed

What it means

validate_instance_name rejects any string containing whitespace characters (spaces, tabs, newlines). Instance names become parts of scorer keys, so whitespace would break key formatting and lookups.

Source

Thrown at src/heretic/config.py:140

            "Optional name to distinguish multiple instances of the same plugin class. "
            "Instance-specific settings live under `[scorer.<ClassName>_<instance_name>]`."
        ),
    )

    @field_validator("instance_name")
    @classmethod
    def validate_instance_name(cls, value: str | None) -> str | None:
        if value is None:
            return value

        if not value.strip():
            raise ValueError("cannot be empty or whitespace")

        if "." in value:
            raise ValueError("'.' is not allowed")

        if any(char.isspace() for char in value):
            raise ValueError("whitespace is not allowed")

        return value


class BenchmarkSpecification(BaseModel):
    task: str = Field(
        description="Task ID of the benchmark in the Language Model Evaluation Harness."
    )

    name: str = Field(description="Name of the benchmark for presentation purposes.")

    description: str = Field(
        description="Description of the benchmark for presentation purposes."
    )


class Settings(BaseSettings):
    model: str = Field(description="Hugging Face model ID, or path to model on disk.")

View on GitHub (pinned to bedb94ef11)

Solutions

1. Remove whitespace: use hyphens or underscores ("my-scorer", "my_scorer")
2. Strip and normalize input: "-".join(value.split()) before validation
3. Quote CLI arguments and use single-token names

Example fix

// before
instance_name = "my scorer"
// after
instance_name = "my-scorer"

if any(c.isspace() for c in (instance_name or "")):
    raise ValueError("instance_name must not contain whitespace")

def is_whitespace_free(name: str) -> bool:
    return isinstance(name, str) and name.strip() == name and not any(c.isspace() for c in name)

try:
    cfg.validate_instance_name(name)
except ValueError:
    name = "-".join(name.split())

When it happens

Trigger: Calling validate_instance_name with values like "my scorer", "scorer\t1", or "name\n" — often from free-text config values or unquoted shell arguments.

Common situations: Multi-word names in config.toml, CLI args passed unquoted ("--instance-name my scorer"), or names read from files with trailing newlines.

Related errors

• '.' is not allowed
• cannot be empty or whitespace
• Duplicate scorer instance name: {scorer_key}. Give each inst
• No scorers configured. Set 'scorers' in config.toml
• prompts must not be empty

AI-assisted analysis of p-e-w/heretic@bedb94ef11 (2026-08-29). Data as JSON: /api/errors/a6f8df672856db19. Report an issue: GitHub.