TheActivity is keyed by that id. If an agent asks for a different value (an email, a support agent contact id, an anonymous session id), it reads the wrong bucket — or an empty one — and the user looks inactive even though they’ve been clicking around.user_idan agent sends must equal theuser_idactivity was stored under — the stable id your activity source identifies the user with.
The id depends on your activity source. Autoplay is source-agnostic — the source set grows over time:
Whichever source you use, the rule is the same: the agent must send that id.
🧩 The three layers that must agree
🤝 How each agent satisfies layer 3
Every agent has its own way of passing a trusted identity to the connector. The mechanism differs per agent; the required value is always the same (your activity source’s stable user id).For anonymous (not-logged-in) users there’s no trusted identity to pass, so an agent can’t reliably pull their activity. This surface is designed for logged-in users your source has identified.
🛟 Debugging “no recent activity”
Almost always an identity mismatch. Confirm the same value appears in all three places:- the id your activity source identifies the user with (e.g. PostHog
identify, Amplitudeuser_id), - whatever your agent uses as its verified identity (e.g. Fin’s JWT
user_idclaim), - the
user_idthe agent actually sends to the MCP tool (or the REST endpoint).
posthog.identify.