We are implementing PDEX PlanNet and we see these 6 (2 searches for 3 resources) search parameters:
https://build.fhir.org/ig/HL7/davinci-pdex-plan-net/SearchParameter-plannet-available-days.html
https://build.fhir.org/ig/HL7/davinci-pdex-plan-net/SearchParameter-plannet-available-start-time.html

Here we can see exact and contains modifiers for token parameters. In HL7 FHIR search page we can't find these 2 modifiers for token types. Based on the description in the search page, by token parameters must be done close to the exact-match searches. Meanwhile seems I understand your motivation for doing so.
But shouldn't we either use string parameters for these searches with exact and contains modifiers or token parameters without exact and contains modifiers?

***Reported via zulip https://chat.fhir.org/#narrow/stream/179166-implementers/topic/PDEX.20Plan.20Net.20exact.20and.20contains.20modifiers.20for.20token