I believe that API simply doesn’t return all clips.
Example from chocotaco:
tcurl -s ‘https://api.twitch.tv/helix/clips?broadcaster_id=69906737&started_at=2020-01-15T18%3A40%3A00Z&ended_at=2020-01-15T18%3A50%3A00Z&first=100’ | jq -r ‘.data | .created_at + " " + .id’ | sort
2020-01-15T18:40:22Z AgitatedHotGazelleNotLikeThis
2020-01-15T18:41:39Z SaltyLitigiousBisonRlyTho
2020-01-15T18:42:23Z EncouragingConcernedCookieCharlietheUnicorn
2020-01-15T18:43:31Z UninterestedShinyCobblerPastaThat
2020-01-15T18:44:34Z StrangeObliviousMonitorPicoMause
2020-01-15T18:44:50Z OnerousViscousLarkChocolateRain
2020-01-15T18:45:40Z CuriousSmilingWheelNerfBlueBlaster
2020-01-15T18:46:17Z HandsomeSillyBunnyPJSugar
2020-01-15T18:46:31Z PoorCovertLeopardYouDontSay
2020-01-15T18:46:54Z NastyCloudyReubenLeeroyJenkins
2020-01-15T18:47:15Z PiercingSmallPonyDeIlluminati
2020-01-15T18:47:37Z EnchantingAverageHyenaSMOrc
2020-01-15T18:48:13Z HilariousInexpensiveBadgerOSkomodo
2020-01-15T18:48:36Z KawaiiFurryWalletPlanking
2020-01-15T18:48:51Z SweetClearBillWholeWheat
"pagination":{}
This request returns 16 clips, however there are many more clips in the same exact time range that don’t get returned. No pagination token either.
Known clips in that range, found via chat or previous requests:
2020-01-15T18:40:22Z AgitatedHotGazelleNotLikeThis
2020-01-15T18:40:58Z ObliviousArbitraryPastaDatSheffy
2020-01-15T18:41:39Z SaltyLitigiousBisonRlyTho
2020-01-15T18:42:23Z EncouragingConcernedCookieCharlietheUnicorn
2020-01-15T18:42:30Z UnusualStupidOryxPeteZaroll
2020-01-15T18:43:21Z PunchyGlutenFreeWoodcockFutureMan
2020-01-15T18:43:31Z UninterestedShinyCobblerPastaThat
2020-01-15T18:43:45Z RockyResourcefulWormSaltBae
2020-01-15T18:44:11Z CrunchyIgnorantCoyoteBibleThump
2020-01-15T18:44:34Z StrangeObliviousMonitorPicoMause
2020-01-15T18:44:50Z OnerousViscousLarkChocolateRain
2020-01-15T18:45:40Z CuriousSmilingWheelNerfBlueBlaster
2020-01-15T18:46:15Z MoldyGiftedShrewVoteNay
2020-01-15T18:46:17Z HandsomeSillyBunnyPJSugar
2020-01-15T18:46:25Z AffluentDeafCheesecakeCopyThis
2020-01-15T18:46:31Z PoorCovertLeopardYouDontSay
2020-01-15T18:46:36Z FrozenPlacidClintBrokeBack
2020-01-15T18:46:39Z OnerousRenownedSkunkImGlitch
2020-01-15T18:46:44Z ExcitedBrainyLapwingMikeHogu
2020-01-15T18:46:53Z TenderEnticingNeanderthalPraiseIt
2020-01-15T18:46:54Z NastyCloudyReubenLeeroyJenkins
2020-01-15T18:46:55Z AuspiciousLaconicSangFreakinStinkin
2020-01-15T18:47:15Z PiercingSmallPonyDeIlluminati
2020-01-15T18:47:26Z PeacefulStylishLionWholeWheat
2020-01-15T18:47:37Z EnchantingAverageHyenaSMOrc
2020-01-15T18:48:13Z HilariousInexpensiveBadgerOSkomodo
2020-01-15T18:48:36Z KawaiiFurryWalletPlanking
2020-01-15T18:48:51Z SweetClearBillWholeWheat
Those clips are all from the same channel in the same time range but many do not get returned.
Edit: Another thing, I had the first request’s result saved for like two weeks now and tried it multiple times since then. At first always giving the same results however one day recently it switched out one of the 16 clips with one of the missing ones and a new one started missing from ranged request. All the other 15 ones stayed the same.
It definitely looks like time ranged requests will just miss about half the clips in the range sometimes.