Session logs and runtimes

Agent Session Protocol

ASP stores and migrates complete session logs between harnesses. OpenCheckpoint holds the distilled working state. A handoff can carry an ASP session alongside a checkpoint, and a checkpoint can reference ASP session and event ids:

{ "protocol": "asp", "id": "6f0d2c1e9b", "event": "evt-a91f" }

ASP’s per-axis fidelity declarations correspond to derivation.omissions, and its approval.requested and task.updated events map to operations and task status.

pi compaction summaries

pi’s compaction summaries use fixed sections that map onto checkpoint fields:

pi summary section	OpenCheckpoint
Goal	task.objective
Constraints & Preferences	statements of kind constraint or instruction
Progress: Done / In Progress / Blocked	progress.completed, progress.focus, progress.next with blocked_by
Key Decisions	statements of kind decision with rationale
Next Steps	progress.next
Read and modified files	resources

A converter from pi compaction entries is a planned early producer.

Runtime checkpoints (LangGraph, OpenAI Agents SDK)

Runtime checkpoints serialize execution state for one engine: graph channels, run state, the current agent object. They suit resuming in the same runtime and do not carry over to another one. A runtime can emit an OpenCheckpoint document alongside its own checkpoint when work must leave the runtime. Pending writes and approval interruptions become operations; thread ids become session_refs.

Open Responses and provider compaction

Provider compaction produces encrypted or signed items that only the issuing provider can use. Any consumer can read an OpenCheckpoint document, so the two complement each other. A checkpoint may reference a response id in session_refs so the same provider can use its own state when available.