Session execution graph

How Checkfu records actors, fidelity, portable continue, and native resume without inventing collaboration.

A Session is the durable record of work that happened inside it. An agent is an attributed projection of that record, not a hidden transcript.

Checkfu does not capture private chain of thought, provider caches, or an uncommitted output suffix.

Event log vs Session Bundle

GET /v1/sessions/{id}/export returns the owned event log: every persisted envelope plus explicit unavailable positions. That is the format checkfu.session-export. It is a complete tape of what happened, not the full Session graph.

A Session Bundle (checkfu.session-bundle) is the complete offline artifact: events or unavailable positions for 1..end_sequence, plus actor, work, recovery, artifact, and capsule sections. The event log cannot render graph, recovery, or learning views by itself. See Export and own your logs.

Portable continue vs native resume

Phrase	Means
Portable continue	Replay canonical semantic context on a compatible harness. Hidden model state is not pretended to exist.
Native resume	Restore a qualified continuation capsule. Stronger only when the exact importer still matches.
SSE reconnect	Resume a dropped event stream with Last-Event-ID. That is a cursor, not native continuation. See Resume a stream.

A failed harness switch keeps the frozen source frontier. It does not advance context.

Adapter fidelity

Unsupported collaboration is not inferred from timing, tool names, or a vendor UI.

Adapter	Subagents	Teams	Workflows	Native transcript
First-party Checkfu harness	complete	flattened	observed	structured
Generic Vercel HarnessAgent	observed	unsupported	unsupported	unsupported
Claude Agent (claude-code)	observed	unsupported	unsupported	unsupported
Codex, Pi, OpenCode, Hermes, Cursor	unsupported	unsupported	unsupported	unsupported
Connected runtime	unsupported	unsupported	unsupported	unsupported
Customer ACP	unsupported	unsupported	unsupported	unsupported

A claimed posture cannot outrank that ceiling. Claude Agent may observe nested tasks; it cannot promote teams or workflows the generic stream does not correlate.

What this does not promise

• Exporting a Session Bundle from the public API (the current export is the event log).
• A public operation that switches an idle thread onto another harness.
• Native resume without a current, qualified capsule.