Function: epochLocations()

epochLocations(source): readonly EpochLocation[]

Defined in: src/lib/time-travel/epochs.ts:217

Every epoch in a recording, in run order — the ONE owner of the flat / grouped fork.

Returns [] for a recording with no LLM call in it at all (an empty log, a chart with no call-llm stage). That is a different fact from "the epoch you asked for is not here", which is what epochAt says with undefined.

MEMOIZED on the recording object, because the cost of locating epochs is a pass over the log and a per-epoch reader asks for one epoch at a time: before this, scrubbing a 600-turn run epoch by epoch relocated every epoch on every call and took 20.8 s. Holding the snapshot and asking it repeatedly is the shape a reader's UI actually has, so the memo is keyed on exactly that object; a caller that hands in a runner and gets a fresh snapshot each time pays the pass each time, which is the cost of asking a different question.

FROZEN, because it is memoized: the array and each location on it are the very objects the next caller gets, so an edit here would be an edit to everybody's answer. The same law keyedFold.ts · freezeDeep states for a folded value. What is NOT frozen is what a location POINTS AT — log, source, runSource are the caller's own recording, and this file does not get to lock down an object it was merely handed.

Parameters

source

unknown

Returns

readonly EpochLocation[]

Example

import { epochLocations } from 'agentfootprint';

epochLocations(agent.getSnapshot()!).map((e) => [e.epoch, e.callRuntimeStageId]);
// dynamic:         [[1, 'call-llm#12'], [2, 'call-llm#31']]
// dynamic-grouped: [[1, 'sf-llm-call/call-llm#9'], [2, 'sf-llm-call/call-llm#28']]