microsoft/semantic-kernel · error · ValueError

Subscription does not exist

Error message

Subscription does not exist

What it means

Thrown by the in-process runtime's subscription manager in remove_subscription(id) when no registered subscription has a matching .id. The check is `any(sub.id == id for sub in self._subscriptions)`; the comparison is against the Subscription object's id field, not the topic type or agent type. It is a plain ValueError and leaves the subscription set unchanged.

Source

Thrown at python/semantic_kernel/agents/runtime/in_process/runtime_impl_helpers.py:66

    @property
    def subscriptions(self) -> Sequence[Subscription]:
        """Get the list of subscriptions."""
        return self._subscriptions

    async def add_subscription(self, subscription: Subscription) -> None:
        """Add a subscription to the manager."""
        # Check if the subscription already exists
        if any(sub == subscription for sub in self._subscriptions):
            raise ValueError("Subscription already exists")

        self._subscriptions.append(subscription)
        self._rebuild_subscriptions(self._seen_topics)

    async def remove_subscription(self, id: str) -> None:
        """Remove a subscription from the manager."""
        # Check if the subscription exists
        if not any(sub.id == id for sub in self._subscriptions):
            raise ValueError("Subscription does not exist")

        def is_not_sub(x: Subscription) -> bool:
            return x.id != id

        self._subscriptions = list(filter(is_not_sub, self._subscriptions))

        # Rebuild the subscriptions
        self._rebuild_subscriptions(self._seen_topics)

    async def get_subscribed_recipients(self, topic: TopicId) -> list[AgentId]:
        """Get the list of recipients subscribed to a topic."""
        if topic not in self._seen_topics:
            self._build_for_new_topic(topic)
        return self._subscribed_recipients[topic]

    # TODO(evmattso): optimize this...
    def _rebuild_subscriptions(self, topics: set[TopicId]) -> None:
        """Rebuild the subscriptions for the given topics."""

View on GitHub (pinned to c028a0c7dc)

Solutions

1. Capture and reuse the exact Subscription.id you added: `sub = TypeSubscription(id='sub-1', ...); await runtime.add_subscription(sub); ...; await runtime.remove_subscription(sub.id)`
2. Before removing, confirm the id exists in the runtime's current subscription list (get_subscriptions / internal listing) and handle a miss explicitly.
3. Wrap the call in try/except ValueError to make removal idempotent if the id may already be gone.

Example fix

// before
await runtime.remove_subscription("my-topic")  # wrong: that's a topic type, not an id

// after
sub = TypeSubscription(id="sub-1", topic_type="my-topic", agent_type="MyAgent")
await runtime.add_subscription(sub)
await runtime.remove_subscription(sub.id)  # correct: the subscription id

ids = {s.id for s in await runtime.get_subscriptions()}  # if a listing API exists
if sub_id not in ids:
    raise KeyError(f"subscription {sub_id} not present; will not call remove")
await runtime.remove_subscription(sub_id)

try:
    await runtime.remove_subscription(sub.id)
except ValueError:
    pass  # already absent; treat removal as idempotent

When it happens

Trigger: Calling `await runtime.remove_subscription("some-id")` where "some-id" was never added, was already removed in a prior call, or belongs to a different runtime instance. The argument must equal the .id of a Subscription previously passed to add_subscription.

Common situations: Passing the topic name or agent_type string instead of the subscription id; calling remove twice; subscriptions added on one InProcessRuntime but removed on another; assuming the id is auto-generated when you actually set it yourself on TypeSubscription/TypePrefixSubscription.

Related errors

• Invalid AgentId key: '{key}'. Must only contain ASCII charac
• Invalid AgentId type: '{type}'. Must be alphanumeric (a-z, 0
• Invalid response from DirectLine Bot.\n{response_data}
• Invalid agent type: {type}. Allowed values MUST match the re
• Invalid agent id: {agent_id}

AI-assisted analysis of microsoft/semantic-kernel@c028a0c7dc (2026-08-13). Data as JSON: /api/errors/340d4df60f8bcf06. Report an issue: GitHub.