🚀 Reply API V3 — Changelog (September 17, 2026)

Six AI Prompts endpoints, holiday-calendar CSV export and the AI SDR duplicate operations came out of Coming soon. Contact import gains a

contactId

dedup key, sequence contacts can be repointed at a different sending mailbox, and Mailbox Procurement is documented ahead of a late-September release.

🟢 Now Live AI Prompts — all six operations out of Coming soon: •

GET /v3/ai-prompts

— List AI prompts •

POST /v3/ai-prompts

— Create a personal AI prompt •

PUT /v3/ai-prompts/{id}

— Update a personal AI prompt •

DELETE /v3/ai-prompts/{id}

— Delete a personal AI prompt •

POST /v3/ai-prompts/preview/sample

— Preview a comment prompt against a sample post •

POST /v3/ai-prompts/preview/linkedin-post

— Preview a comment prompt against a LinkedIn post Scopes unchanged:

sequences:read

to list,

sequences:write

to create/update/delete,

sequences:operate

for both previews. Sequence Contacts — repoint contacts at a different sending mailbox: •

POST /v3/sequences/{id}/contacts/set-email-account

(

sequences:operate

) Body takes

contactIds

(1–100, positive, no duplicates) and

emailAccountId

. The mailbox must already be linked to the sequence — link it with

POST /v3/sequences/{id}/email-account-links

first, otherwise you get

400 sequenceContact.invalidInput

. The

200

is non-atomic:

assigned

lists the ids now sending from that mailbox (including ones already on it, so repeating the call is safe),

notProcessed

maps the rest to a reason (

notInSequence

,

unknown

). Owner-only (

403

); archived sequence →

409 sequenceContact.sequenceArchived

. Also out of Coming soon: •

GET /v3/holiday-calendars/{id}/export-csv

— Export a holiday calendar as CSV •

POST /v3/ai-sdr/offers/{id}/duplicate

— Duplicate an offer •

POST /v3/ai-sdr/playbooks/{id}/duplicate

— Duplicate a playbook Contact import — match existing contacts by Reply contact id

POST /v3/contacts/import

accepts

options.keys.contactId

(boolean, default

false

) and a

contactId

on each item (integer, nullable). Two rules worth noting: the key is not additive — when enabled it decides the match on its own and the other keys are not consulted; and every item must then carry a

contactId

, where an id that doesn't resolve inside your team is imported as a new contact rather than failing. Available only to teams it has been enabled for — otherwise

403 contact.forbidden

with

Matching contacts by contactId is not enabled for your team.

🔜 Coming Soon Mailbox Procurement — buy domains and mailboxes through the API (targeted: late September 2026, not callable yet): •

GET /v3/email-accounts/procurement/domains/available

(

channels:read

) •

POST /v3/email-accounts/procurement/domains/estimate

(

channels:read

) •

POST /v3/email-accounts/procurement/domains/purchase

(

channels:write

) •

POST /v3/email-accounts/procurement/users

(

channels:write

) What to expect: every monetary amount is in cents (

1299

= $12.99). Domain search takes one label (up to 63 chars, letters/digits/hyphens, no leading or trailing hyphen) against up to 5 TLDs from

com

,

net

,

org

,

biz

,

live

. Orders specify

serviceProvider

of

google

or

microsoft

and 1–5 mailboxes, with unique usernames and exactly one

isAdmin: true

. Purchase is async —

202

+

jobId

, poll

GET /v3/background-jobs/{jobId}

. Registration is a precondition: every other procurement endpoint returns

403

until

POST /v3/email-accounts/procurement/users

succeeds. Contacts — bulk opt-out (targeted: late September 2026): •

POST /v3/contacts/set-opted-out

(

contacts:operate

) —

contactIds

(1–100, no duplicates) +

isOptedOut

. Opting out finishes the contacts in every sequence they're in; the

contact_opted_out

webhook fires once per enrolled sequence, and not at all for a contact in no sequence. The

200

lists only per-item failures (

notFound

,

invalidInput

);

{}

means all succeeded. ⚠️ Breaking Changes 1.

steps

is now required when creating a sequence

Before:

POST /v3/sequences

required only

name

.

After:

steps

is required with

minItems: 1

— a sequence with no steps has nothing to send and cannot be started.

Action required: if you create an empty sequence and add steps in a follow-up call, move at least one step into the create request body.

2. Inbox category pages moved

Before:

/api-reference/inbox/list-inbox-categories

and six sibling pages.

After: the

Inbox

tag split into Inbox (Threads, 13 ops) and Inbox Categories (7 ops); category pages now live at

/api-reference/inbox-categories/…

.

Action required: documentation links only — no endpoint, request or response changed. Redirects are in place, so existing links still resolve.

Housekeeping • The per-endpoint Beta banner is replaced by a New banner across 57 operations, meaning "recently shipped" with an invitation to give feedback — never a breaking-change warning. The API-wide Beta signal now appears once, as a pill beside the version. • The API reference is regrouped into 12 top-level sections, including the new Mailbox Procurement. • New schema pages: Available Domain, Estimate Seats. • The spec now declares

openapi: 3.2.0

(was

3.1.0

) to use hierarchical tags. 📚 Full documentation