Trajectory renders a turn-aware event ledger with selectable User, Assistant, Tool, and nested Subtool records. Thick rules mark Turn boundaries, compact inline markers identify Steps, and the main ledger keeps only index, event, and content; selection opens a local inspector for token usage, duration, Input, Output, and Timing. A standalone compaction request appears chronologically in its own Between turns section, while a numbered compaction remains inside its owning turn. A fixed Overview above the ledger projects real record start/duration timing from left to right; dragging an interval focuses the ledger on every record active at any point in that inclusive range, while clearing the selection restores the full branch. The runtime's independent history source supplies raw context lineage and projects cancellation-frozen Assistant and Tool records, so Trajectory neither reads nor changes the Chat conversation snapshot. The package remains a pure-consumer plugin (registers one view tab into the conversation's 'conversation.view' slot ring, provides no service, declares no Context merge). Contract: api-contracts v3 §8.

Model Experience

None, as the trajectory views render session data in the browser; nothing here reaches a model request.

KV Cache effect

None; this package neither assembles nor sends a provider request.

Known Limitations and Deferred Work

In-flight Time stays blank — partial / runningCalls rows show their running state without a fabricated duration until a live clock policy lands, so the Overview renders a start marker rather than inventing a live span; record and timeline selection are intentionally local to Trajectory; anchor deep-linking remains deferred.