Typed ids

What the prefixes mean, and how ids travel.

Every id the API, MCP and webhooks show has a prefix that says what it is, then 26 letters and digits: cus_01j30x4zjafcy9tbjzd9xrs78e. Send them back as you got them. An id of the wrong kind is refused with a 400 (input), so a product id can't be passed where a customer's belongs. Prefixes don't change, so you can store ids as they are.

Kind	Prefix	Fields that hold one
organization	`org_`	`organizationId`
business	`biz_`	`businessId`
location	`loc_`	`locationId`, `primaryLocationId`
customer	`cus_`	`customerId`, `keepId`, `mergeId`, `mergedIntoId`, `mergedFrom`, `asCustomerId`, `attendeeCustomerId`, `fromAttendeeCustomerId`
product	`prd_`	`productId`, `freeProductId`
agreement	`agr_`	`agreementId`
charge	`chg_`	`paymentId`, `chargeId`
booking	`bk_`	`bookingId`, `enrollmentId`, `visitId`, `reservationId`
person	`per_`	`personId`
invite	`inv_`	`inviteId`
token	`tok_`	`tokenId`
app	`app_`
dependent	`dep_`	`dependentId`, `attendeeDependentId`
contact	`ct_`	`contactId`
note	`note_`	`noteId`
offering	`off_`	`offeringId`
session	`ses_`	`sessionId`, `fromSessionId`, `toSessionId`
admission	`adm_`	`admissionId`
pattern	`pat_`	`patternId`
standing	`stb_`	`standingId`
attendance	`att_`	`attendanceId`
resource	`res_`	`resourceId`, `calendarId`
resource group	`rgp_`	`groupId`
reservation	`rsv_`
pool	`pool_`	`poolId`
line	`ln_`
variant	`var_`	`variantId`
price	`pri_`	`priceId`
price version	`prv_`
adjustment	`adj_`	`adjustmentId`
adjustment version	`adv_`
audience	`aud_`	`audienceId`
audience link	`aul_`
code	`cod_`	`codeId`
grant	`grt_`	`grantId`
gift card	`gc_`	`giftCardId`
order	`ord_`	`orderId`
policy	`pol_`	`policyId`
quote request	`qr_`
payment account	`pac_`
ledger entry	`led_`
loyalty program	`lyp_`	`programId`
pay rule	`prl_`	`ruleId`
pay statement	`pst_`	`statementId`
pay line	`pyl_`
form	`frm_`	`formId`
submission	`sub_`	`submissionId`
requirement result	`rr_`	`resultId`
file	`fil_`	`fileId`, `withFileId`, `coverFileId`, `attachmentId`, `mediaId`
upload link	`upl_`
album	`alb_`	`albumId`, `collectionId`
field	`fld_`	`fieldId`
conversation	`cnv_`	`conversationId`
conversation message	`cvm_`	`messageId`
message	`msg_`
notification	`ntf_`	`notificationId`
push device	`dev_`
channel contact	`chc_`
campaign	`cmp_`	`campaignId`
broadcast	`brc_`	`broadcastId`
review	`rev_`	`reviewId`
social post	`soc_`	`contentId`
email sender	`snd_`
sms registration	`smr_`
site	`site_`	`siteId`
site comment	`cmt_`	`commentId`
post	`post_`	`postId`
domain	`dom_`
gallery	`gal_`	`galleryId`
gallery set	`gst_`	`setId`
gallery viewer	`gvw_`
gallery download	`gdl_`
proposal	`prp_`	`proposalId`
approval	`apv_`	`approvalId`
workflow	`wfl_`	`workflowId`
suggestion	`sug_`	`suggestionId`
memory	`mem_`	`memoryId`
run	`run_`
job	`job_`	`jobId`, `retryJobId`
pending operation	`pnd_`	`operationId`
event	`evt_`	`eventId`
audit entry	`log_`
integration	`int_`	`integrationId`
integration item	`iti_`
webhook endpoint	`whe_`	`endpointId`
webhook delivery	`whd_`	`deliveryId`
import run	`imp_`
brand version	`brv_`
business plan	`bpl_`
plan version	`plv_`
waitlist signup	`wls_`
formation order	`fmo_`	`formationOrderId`
filing	`fln_`	`deadlineId`
checklist	`chk_`	`checklistId`
checklist item	`chi_`
requirement	`req_`	`requirementId`
compliance report	`rpt_`	`reportId`
issue	`iss_`	`issueId`
support session	`sup_`	`supportSessionId`
mail	`mail_`
capability gap	`gap_`

An object's own id is typed by where it sits: the items of customers are customers, a booking is a booking.