rohitg00/ai-engineering-from-scratch · error · ValueError

unknown event type: {etype}

Error message

unknown event type: {etype}

What it means

Error "unknown event type: {etype}" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at phases/19-capstone-projects/20-agent-harness-loop-contract/code/main.py:182

        self._goal: str = ""
        self._plan: list[Step] = []
        self._cursor: int = 0
        self._events: list[Event] = []
        self._history: list[Step] = []
        self._reason: str = ""
        self._prev_state: State | None = None

    @property
    def events(self) -> list[Event]:
        return list(self._events)

    @property
    def plan(self) -> list[Step]:
        return list(self._plan)

    def _emit(self, etype: str, payload: dict) -> None:
        if etype not in EVENT_TYPES:
            raise ValueError(f"unknown event type: {etype}")
        self._events.append(Event(type=etype, payload=payload, ts=time.time()))

    def _transition(self, target: State) -> None:
        legal: dict[State, set[State]] = {
            State.IDLE: {State.PLANNING},
            State.PLANNING: {State.EXECUTING, State.IDLE, State.DONE},
            State.EXECUTING: {State.AWAITING_TOOL, State.REFLECTING, State.IDLE},
            State.AWAITING_TOOL: {State.REFLECTING, State.IDLE},
            State.REFLECTING: {State.PLANNING, State.EXECUTING, State.DONE, State.IDLE},
            State.DONE: set(),
        }
        if target not in legal[self.state]:
            raise RuntimeError(f"illegal transition {self.state.value} -> {target.value}")
        self.state = target

    def _check_budget(self) -> PullRequest | None:
        which = self.budget.exceeded()
        if which is None:

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at phases/19-capstone-projects/20-agent-harness-loop-contract/code/main.py:182 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of rohitg00/ai-engineering-from-scratch@39ea8a1c6d (2026-08-26). Data as JSON: /api/errors/a7c1225aa670addf. Report an issue: GitHub.