HKUDS/DeepTutor · error · OpValidationError

add: text length must be 1..{_MAX_TEXT_LEN} (got {len(op.tex

Error message

add: text length must be 1..{_MAX_TEXT_LEN} (got {len(op.text)})

What it means

OpValidationError from ops.apply's _validate: an AddOp's text must be non-empty and at most _MAX_TEXT_LEN characters. AddOp appends a new memory entry, and oversized/empty text would break the document format and L2 budgets, so it is rejected up front before any mutation occurs (validation is atomic — no partial apply).

Source

Thrown at deeptutor/services/memory/ops.py:75

@dataclass
class ApplyReport:
    accepted: bool
    results: list[OpResult] = field(default_factory=list)
    reason: str = ""


class OpValidationError(Exception):
    """Raised when a batch fails pre-flight validation."""


def _validate(doc: Document, ops: list[Op]) -> None:
    edits: set[str] = set()
    deletes: set[str] = set()

    for op in ops:
        if isinstance(op, AddOp):
            if not op.text or len(op.text) > _MAX_TEXT_LEN:
                raise OpValidationError(
                    f"add: text length must be 1..{_MAX_TEXT_LEN} (got {len(op.text)})"
                )
            if not op.section or len(op.section) > _MAX_SECTION_LEN:
                raise OpValidationError(f"add: invalid section {op.section!r}")
            if not op.refs:
                raise OpValidationError("add: refs must be non-empty")
            for ref in op.refs:
                if not is_valid_ref(ref):
                    raise OpValidationError(f"add: malformed ref {ref!r}")
        elif isinstance(op, EditOp):
            if not is_entry_id(op.target_id):
                raise OpValidationError(f"edit: malformed target_id {op.target_id!r}")
            if doc.find(op.target_id) is None:
                raise OpValidationError(f"edit: target_id {op.target_id} not found")
            if not op.new_text or len(op.new_text) > _MAX_TEXT_LEN:
                raise OpValidationError(
                    f"edit: text length must be 1..{_MAX_TEXT_LEN} (got {len(op.new_text)})"
                )

View on GitHub (pinned to 3e82f13042)

Solutions

1. Clamp or reject the text before building the op: if not text or len(text) > _MAX_TEXT_LEN, skip/split the write
2. Split very long content into multiple AddOps (each within the limit) or summarize it down
3. Import _MAX_TEXT_LEN from deeptutor.services.memory.ops and validate against the library's own constant instead of hardcoding

Example fix

# before
op = AddOp(text=long_note, section="facts", refs=[ref])
result = ops.apply(doc, [op])

# after
from deeptutor.services.memory.ops import _MAX_TEXT_LEN
if long_note and len(long_note) <= _MAX_TEXT_LEN:
    op = AddOp(text=long_note, section="facts", refs=[ref])
    result = ops.apply(doc, [op])

from deeptutor.services.memory.ops import _MAX_TEXT_LEN, OpValidationError
assert isinstance(text, str) and 1 <= len(text) <= _MAX_TEXT_LEN

def is_valid_add_text(text: str) -> bool:
    return bool(text) and len(text) <= _MAX_TEXT_LEN

try:
    result = ops.apply(doc, ops_list)
except OpValidationError as e:
    if e.args[0].startswith("add: text length"):
        text = text[:_MAX_TEXT_LEN]
        ops_list = rebuild(ops_list, text=text)
        result = ops.apply(doc, ops_list)
    else:
        raise

When it happens

Trigger: Constructing AddOp(text='', section=..., refs=[...]) or AddOp with text longer than _MAX_TEXT_LEN (typically an LLM generating a bloated or empty memory note) and passing it to ops.apply(doc, [op]).

Common situations: LLM-generated memory writes without length clamping; truncating user input to the wrong bound; unit tests exercising validation boundaries; copying constants from another module with a different _MAX_TEXT_LEN.

Related errors

• edit: text length must be 1..{_MAX_TEXT_LEN} (got {len(op.ne
• add: invalid section {op.section!r}
• add: refs must be non-empty
• add: malformed ref {ref!r}
• edit: malformed target_id {op.target_id!r}

AI-assisted analysis of HKUDS/DeepTutor@3e82f13042 (2026-08-27). Data as JSON: /api/errors/6a415d252fa1348f. Report an issue: GitHub.