# Sendmux > The intelligent email layer ## Docs - [Get current balance](https://sendmux.ai/docs/api/billing/get-current-balance.md): Returns the current team balance and auto top-up configuration. - [Get spend summary](https://sendmux.ai/docs/api/billing/get-spend-summary.md): Returns a spend summary over a configurable lookback period. - [List transactions](https://sendmux.ai/docs/api/billing/list-transactions.md): Returns paginated credit transaction history with optional type filter. Uses cursor-based pagination ordered by created_at descending — pass `cursor=` from the previous response to fetch the next page. - [Get domain-wide sender filters](https://sendmux.ai/docs/api/domain-filters/get-domain-wide-sender-filters.md): Returns the current sender-filter mode and rule set applied to every mailbox under this domain. Per-mailbox rules take precedence at match time. - [Replace domain-wide sender filters](https://sendmux.ai/docs/api/domain-filters/replace-domain-wide-sender-filters.md): Atomically replaces the sender-filter mode and rule set for an entire domain. Applies to every mailbox under the domain unless that mailbox has its own per-mailbox rules (which take precedence). Maximum 1000 rules per request. - [Add a mailbox domain](https://sendmux.ai/docs/api/domains/add-a-mailbox-domain.md): Creates a new sending domain and returns the DNS records the customer must place before verification can succeed. Provisioning touches both our mail platform and Amazon SES — on any failure the partial state is automatically rolled back. - [Delete a mailbox domain](https://sendmux.ai/docs/api/domains/delete-a-mailbox-domain.md): Removes a domain from our mail platform, Amazon SES, and Sendmux. Blocked if any active mailbox still uses the domain — delete those mailboxes first. - [Download a domain as a zone file](https://sendmux.ai/docs/api/domains/download-a-domain-as-a-zone-file.md): Returns the domain's DNS records formatted as a BIND-style zone file fragment. Suitable for direct paste into a DNS provider that accepts zone-file imports. - [Get a mailbox domain](https://sendmux.ai/docs/api/domains/get-a-mailbox-domain.md): Returns a single domain including its DNS records and latest verification state. Responses carry a weak `ETag` header — send it back as `If-None-Match` on the next request and the server will return `304 Not Modified` (no body) when the resource has not changed. - [List mailbox domains](https://sendmux.ai/docs/api/domains/list-mailbox-domains.md): Returns a cursor-paginated list of sending domains configured for the team, ordered by `created_at` descending. Each entry includes the DNS records the customer must place, the current verification status, and the SES DKIM state. Pass `cursor=` from the previous response to fetch the ne… - [Verify a mailbox domain](https://sendmux.ai/docs/api/domains/verify-a-mailbox-domain.md): Runs an immediate DNS-over-HTTPS check of the domain's MX, SPF, DMARC and ownership TXT records, then asks SES for the latest DKIM status. If every check passes the domain is marked verified. Domains automatically re-verify every 6 hours — this endpoint is only needed to trigger a check on demand. - [Get delivery log](https://sendmux.ai/docs/api/emails/get-delivery-log.md): Returns a single delivery log by its public ID. Responses carry a weak `ETag` header — send it back as `If-None-Match` on the next request and the server will return `304 Not Modified` (no body) when the log has not changed. Logs in a terminal status (sent/failed/rejected) stop changing, so 304 repl… - [Get email metrics](https://sendmux.ai/docs/api/emails/get-email-metrics.md): Returns aggregated email delivery counts with flexible time windowing and comparison period. - [List delivery logs](https://sendmux.ai/docs/api/emails/list-delivery-logs.md): Returns paginated delivery logs with cursor-based pagination and filters. - [Send a batch of emails](https://sendmux.ai/docs/api/emails/send-a-batch-of-emails.md): Queue up to 100 emails for delivery in a single request. Uses partial success model — individual message failures do not fail the entire batch. Requires `email.send` permission. - [Send a single email](https://sendmux.ai/docs/api/emails/send-a-single-email.md): Queue a single email for delivery. Requires `email.send` permission. - [Errors](https://sendmux.ai/docs/api/errors.md): Error codes and handling for the Sendmux API. - [Get incoming log](https://sendmux.ai/docs/api/inboxes/get-incoming-log.md): Returns one incoming message log by public ID. - [List incoming logs](https://sendmux.ai/docs/api/inboxes/list-incoming-logs.md): Returns paginated incoming message logs for billing accountability. - [Introduction](https://sendmux.ai/docs/api/introduction.md): Programmatic access to your Sendmux email infrastructure. - [Batch delete mailbox messages](https://sendmux.ai/docs/api/mailbox-api/batch-delete-mailbox-messages.md): Moves up to 100 messages to Trash by default with state-safe conflict handling. Set `permanent=true` to permanently delete them. - [Batch get mailbox messages](https://sendmux.ai/docs/api/mailbox-api/batch-get-mailbox-messages.md): Returns exact messages by ID. Use `body_mode` to choose summary-only output, raw body output, or clean JSON content. Attachment output remains metadata only; attachment contents are not parsed. - [Batch update mailbox messages](https://sendmux.ai/docs/api/mailbox-api/batch-update-mailbox-messages.md): Updates allowed message flags and keywords for up to 100 messages with state-safe conflict handling. - [Count mailbox messages](https://sendmux.ai/docs/api/mailbox-api/count-mailbox-messages.md): Returns a count for the supplied mailbox message filters without returning message rows. - [Create a mailbox folder](https://sendmux.ai/docs/api/mailbox-api/create-a-mailbox-folder.md): Creates a folder in the authenticated mailbox. - [Delete a mailbox folder](https://sendmux.ai/docs/api/mailbox-api/delete-a-mailbox-folder.md): Deletes an empty custom folder unconditionally unless `If-Match` is supplied. Built-in folders and non-empty folders cannot be deleted. Send `If-Match` with a prior ETag to reject stale deletes. - [Delete a mailbox message](https://sendmux.ai/docs/api/mailbox-api/delete-a-mailbox-message.md): Moves a message to Trash by default, unconditionally unless `If-Match` is supplied. Set `permanent=true` to permanently delete it. Send `If-Match` with a prior ETag to reject stale deletes. - [Download a message attachment](https://sendmux.ai/docs/api/mailbox-api/download-a-message-attachment.md): Streams one attachment from a message in the authenticated mailbox. Supports standard byte ranges. - [Get a mailbox folder](https://sendmux.ai/docs/api/mailbox-api/get-a-mailbox-folder.md): Returns one folder from the authenticated mailbox. Responses include a weak `ETag` header. - [Get a mailbox message](https://sendmux.ai/docs/api/mailbox-api/get-a-mailbox-message.md): Returns one message from the authenticated mailbox. Responses include a weak `ETag` header. - [Get a mailbox submission](https://sendmux.ai/docs/api/mailbox-api/get-a-mailbox-submission.md): Returns one send submission for the authenticated mailbox. Responses include a weak `ETag` header. - [Get a mailbox thread](https://sendmux.ai/docs/api/mailbox-api/get-a-mailbox-thread.md): Returns thread metadata, message IDs, participants, last message, unread count, and state for one conversation. Responses include a weak `ETag` header. - [Get clean message content](https://sendmux.ai/docs/api/mailbox-api/get-clean-message-content.md): Returns deterministic clean JSON content for one message. Attachment output is metadata only; attachment contents are not parsed by this endpoint. - [Get clean thread content](https://sendmux.ai/docs/api/mailbox-api/get-clean-thread-content.md): Returns a cursor-paginated clean JSON view of messages in a thread. Attachment output is metadata only; attachment contents are not parsed by this endpoint. - [Get folder changes](https://sendmux.ai/docs/api/mailbox-api/get-folder-changes.md): Returns folder changes since a prior folder state, or the current folder state when omitted. - [Get folder query changes](https://sendmux.ai/docs/api/mailbox-api/get-folder-query-changes.md): Returns folder-list index changes since a prior folder query state, or the current folder query state when omitted. - [Get mailbox API session](https://sendmux.ai/docs/api/mailbox-api/get-mailbox-api-session.md): Returns mailbox API capabilities, resource state tokens, limits, and disabled feature flags for the authenticated mailbox. - [Get mailbox changes](https://sendmux.ai/docs/api/mailbox-api/get-mailbox-changes.md): Returns message changes in the legacy shape when `types` is omitted. Pass a comma-separated `types` list for a typed state map. - [Get mailbox sender identity](https://sendmux.ai/docs/api/mailbox-api/get-mailbox-sender-identity.md): Returns the default sender identity and signatures for the authenticated mailbox. - [Get mailbox usage](https://sendmux.ai/docs/api/mailbox-api/get-mailbox-usage.md): Returns a compact usage view derived from mailbox quota records. Responses include a weak `ETag` header. - [Get message query changes](https://sendmux.ai/docs/api/mailbox-api/get-message-query-changes.md): Returns filtered message-list index changes since a prior message query state, or the current message query state when omitted. - [Get message search snippets](https://sendmux.ai/docs/api/mailbox-api/get-message-search-snippets.md): Returns subject and preview snippets for a text search. Provide `message_ids` to snippet exact messages, or omit it to snippet the first filtered results. - [Get quota changes](https://sendmux.ai/docs/api/mailbox-api/get-quota-changes.md): Returns quota changes since a prior quota state, or the current quota state when omitted. - [Get raw message body](https://sendmux.ai/docs/api/mailbox-api/get-raw-message-body.md): Returns raw message body content for the authenticated mailbox. This endpoint does not strip signatures, strip quoted replies, extract links, or clean the body into a structured content shape. - [Get submission changes](https://sendmux.ai/docs/api/mailbox-api/get-submission-changes.md): Returns send submission changes since a prior submission state, or the current state when omitted. - [List granted mailboxes](https://sendmux.ai/docs/api/mailbox-api/list-granted-mailboxes.md): Lists the mailboxes available to the current mailbox credential or connected app. Use this before choosing a `mailbox_id` for mailbox actions when more than one mailbox is available. - [List mailbox folders](https://sendmux.ai/docs/api/mailbox-api/list-mailbox-folders.md): Returns a cursor-paginated list of folders for the authenticated mailbox. - [List mailbox messages](https://sendmux.ai/docs/api/mailbox-api/list-mailbox-messages.md): Returns a cursor-paginated list of messages for the authenticated mailbox. Requires a mailbox API key. - [List mailbox quotas](https://sendmux.ai/docs/api/mailbox-api/list-mailbox-quotas.md): Returns a cursor-paginated list of quota usage and limits for the authenticated mailbox. - [List mailbox sender identities](https://sendmux.ai/docs/api/mailbox-api/list-mailbox-sender-identities.md): Returns sender identities available to the authenticated mailbox. - [List mailbox submissions](https://sendmux.ai/docs/api/mailbox-api/list-mailbox-submissions.md): Returns a cursor-paginated list of send submissions for the authenticated mailbox, including delivery lifecycle fields when available. - [List mailbox threads](https://sendmux.ai/docs/api/mailbox-api/list-mailbox-threads.md): Returns a cursor-paginated list of conversation threads for the authenticated mailbox. Filter by text, participant, folder, unread state, attachment presence, or date range. - [List thread messages](https://sendmux.ai/docs/api/mailbox-api/list-thread-messages.md): Returns cursor-paginated message summaries for one thread. Use the thread content endpoint when you need cleaned bodies. - [Self-introspect the calling mailbox](https://sendmux.ai/docs/api/mailbox-api/self-introspect-the-calling-mailbox.md): Returns the mailbox the bearer token is scoped to, including live storage usage. Intended for SDK auto-discovery — call once on startup to resolve the mailbox ID. Requires a mailbox-scoped API key; root keys receive 403. - [Send a mailbox message](https://sendmux.ai/docs/api/mailbox-api/send-a-mailbox-message.md): Creates and queues a message from the authenticated mailbox. Supply an `Idempotency-Key` header to safely retry. Attachments may use small inline base64 content or blob IDs returned by `POST /mailbox/attachments:upload`. - [Stream mailbox events](https://sendmux.ai/docs/api/mailbox-api/stream-mailbox-events.md): Streams bounded rich mailbox events for connected clients. Each received-message event includes subject, participants, preview, attachment metadata, and a capped body snapshot; use the message endpoints for full content or attachment bytes. - [Update a mailbox folder](https://sendmux.ai/docs/api/mailbox-api/update-a-mailbox-folder.md): Updates a folder unconditionally unless `If-Match` is supplied. Send `If-Match` with a prior ETag to reject stale edits. - [Update mailbox message flags](https://sendmux.ai/docs/api/mailbox-api/update-mailbox-message-flags.md): Updates mutable message flags and keywords unconditionally unless `If-Match` is supplied. Send `If-Match` with a prior ETag to reject stale edits. - [Update mailbox sender identity](https://sendmux.ai/docs/api/mailbox-api/update-mailbox-sender-identity.md): Updates the default sender name, plain text signature, and HTML signature for the authenticated mailbox. - [Upload a mailbox attachment](https://sendmux.ai/docs/api/mailbox-api/upload-a-mailbox-attachment.md): Uploads one attachment as binary data and returns a blob ID that can be supplied to `POST /mailbox/messages/send`. - [Get mailbox sender filters](https://sendmux.ai/docs/api/mailbox-filters/get-mailbox-sender-filters.md): Returns the current sender-filter mode and rule set for a mailbox. Mailbox-scoped rules override any domain-wide rules set on the parent domain. - [Replace mailbox sender filters](https://sendmux.ai/docs/api/mailbox-filters/replace-mailbox-sender-filters.md): Atomically replaces the sender-filter mode and rule set for a mailbox. The entire rule set is swapped in a single operation — there is no intermediate state where the mailbox has a partial ruleset. A maximum of 1000 rules per request is enforced. - [Create a mailbox](https://sendmux.ai/docs/api/mailboxes/create-a-mailbox.md): Provisions a new mailbox plus an initial bearer token and matching IMAP/SMTP mailbox password. The domain portion of the email must already be verified via POST /domains. If supplied, `quota_bytes` must be one of the current storage tiers: 1073741824 (1 GB), 5368709120 (5 GB), or 53687091200 (50 GB)… - [Create a mailbox API key](https://sendmux.ai/docs/api/mailboxes/create-a-mailbox-api-key.md): Mints an additional bearer token plus IMAP/SMTP mailbox password for an existing mailbox. The plaintext key and password are shown exactly once — store them immediately. - [Delete a mailbox](https://sendmux.ai/docs/api/mailboxes/delete-a-mailbox.md): Removes a mailbox from our mail platform, Amazon SES (for `@myagent.mx` addresses), and Sendmux. All associated API keys are revoked. - [Get a mailbox](https://sendmux.ai/docs/api/mailboxes/get-a-mailbox.md): Returns a single mailbox, tenant-scoped to the caller's team. Responses carry a weak `ETag` header — send it back as `If-None-Match` on the next request and the server will return `304 Not Modified` (no body) when the resource has not changed. The same ETag is the value to use in `If-Match` on PATCH… - [List mailboxes](https://sendmux.ai/docs/api/mailboxes/list-mailboxes.md): Returns a cursor-paginated list of mailboxes configured for the team, ordered by `created_at` descending. Pass `cursor=` from the previous response to fetch the next page. - [Resume a mailbox](https://sendmux.ai/docs/api/mailboxes/resume-a-mailbox.md): Restores a suspended mailbox so it can authenticate, receive mail, and send from the mailbox address again. The operation is idempotent and accepts `Idempotency-Key` for safe retries. - [Revoke a mailbox API key](https://sendmux.ai/docs/api/mailboxes/revoke-a-mailbox-api-key.md): Revokes a specific bearer token + matching mailbox password. Idempotent on already-revoked keys. - [Suspend a mailbox](https://sendmux.ai/docs/api/mailboxes/suspend-a-mailbox.md): Suspends a mailbox without deleting messages, credentials, or settings. Suspended mailboxes cannot receive mail, authenticate to mailbox protocols, or send from the mailbox address. The operation is idempotent and accepts `Idempotency-Key` for safe retries. - [Update a mailbox](https://sendmux.ai/docs/api/mailboxes/update-a-mailbox.md): Updates any combination of display_name, quota_bytes, and send_scope on a mailbox. The display_name and send_scope changes land in a single transaction; quota_bytes is applied afterwards because it also updates external state on our mail platform. Quota can only be set to 1073741824 (1 GB), 53687091… - [Activate a sending account](https://sendmux.ai/docs/api/sending-accounts/activate-a-sending-account.md): Enables a sending account. OAuth accounts without an active connection are moved to pending until reconnected in the dashboard. The shared Amazon SES account can be activated. - [Create an SMTP sending account](https://sendmux.ai/docs/api/sending-accounts/create-an-smtp-sending-account.md): Creates a custom SMTP sending account. Supply an `Idempotency-Key` header to safely retry on network errors. The SMTP password is stored securely and is never returned. - [Deactivate a sending account](https://sendmux.ai/docs/api/sending-accounts/deactivate-a-sending-account.md): Disables a sending account. The shared Amazon SES account can be deactivated. - [Delete a sending account](https://sendmux.ai/docs/api/sending-accounts/delete-a-sending-account.md): Deletes a custom or connected sending account. The shared Amazon SES account cannot be deleted. - [Get a sending account](https://sendmux.ai/docs/api/sending-accounts/get-a-sending-account.md): Returns one sending account. Responses include an ETag for conditional GET and optimistic PATCH. - [Get sending account limits](https://sendmux.ai/docs/api/sending-accounts/get-sending-account-limits.md): Returns custom-account capacity and shared Amazon SES daily sending limit state. - [Get sending account statistics](https://sendmux.ai/docs/api/sending-accounts/get-sending-account-statistics.md): Returns aggregate counts of configured sending accounts with breakdowns by type and status. - [Get sending account usage](https://sendmux.ai/docs/api/sending-accounts/get-sending-account-usage.md): Returns per-account delivery-log counts for today and the trailing 7-day window. - [Get shared Amazon SES limit request state](https://sendmux.ai/docs/api/sending-accounts/get-shared-amazon-ses-limit-request-state.md): Returns the shared Amazon SES daily limit state and any pending increase request. - [List sending accounts](https://sendmux.ai/docs/api/sending-accounts/list-sending-accounts.md): Returns a cursor-paginated list of sending accounts. Credentials are never returned. The shared Amazon SES account is included and marked with `is_shared: true`. - [Request a sending account limit increase](https://sendmux.ai/docs/api/sending-accounts/request-a-sending-account-limit-increase.md): Creates a request to increase the number of custom or connected sending accounts allowed for the team. - [Request a shared Amazon SES daily limit increase](https://sendmux.ai/docs/api/sending-accounts/request-a-shared-amazon-ses-daily-limit-increase.md): Creates a review request for the shared Amazon SES daily sending limit. This does not modify the limit directly. - [Test an SMTP sending account](https://sendmux.ai/docs/api/sending-accounts/test-an-smtp-sending-account.md): Runs a connection test for a custom SMTP account. The shared Amazon SES account and OAuth accounts cannot be tested through this endpoint. - [Update a sending account](https://sendmux.ai/docs/api/sending-accounts/update-a-sending-account.md): Updates a custom sending account. The shared Amazon SES account cannot be edited here; use activate/deactivate and the limit-request endpoint for the allowed shared-account actions. - [Create a webhook subscription](https://sendmux.ai/docs/api/webhooks/create-a-webhook-subscription.md): Creates a new webhook subscription and returns the signing secret ONCE in the response body. Store it securely — it cannot be retrieved later. Use `POST /webhooks/{id}/rotate-secret` to issue a new one. - [Delete a webhook subscription](https://sendmux.ai/docs/api/webhooks/delete-a-webhook-subscription.md): Permanently removes the subscription. In-flight retries are dropped. - [Get a webhook delivery payload](https://sendmux.ai/docs/api/webhooks/get-a-webhook-delivery-payload.md): Returns the retained JSON request body for one delivery attempt. Payloads are retained for 7 days and may no longer be available after `payload_expires_at`. - [Get a webhook subscription](https://sendmux.ai/docs/api/webhooks/get-a-webhook-subscription.md): Returns a single webhook subscription. The signing secret is never included. Responses carry a weak `ETag` header — send it back as `If-None-Match` on the next request and the server will return `304 Not Modified` (no body) when the resource has not changed. The same ETag is the value to use in `If-… - [List webhook delivery attempts](https://sendmux.ai/docs/api/webhooks/list-webhook-delivery-attempts.md): Returns recent delivery attempts for one webhook subscription, ordered by `created_at` descending. Delivery metadata is retained for 7 days. Use the payload endpoint while `payload_available` is true to inspect the exact JSON request body that was delivered. - [List webhook subscriptions](https://sendmux.ai/docs/api/webhooks/list-webhook-subscriptions.md): Returns a cursor-paginated list of webhook subscriptions configured for the team, ordered by `created_at` descending. The signing secret is never included. Pass `cursor=` from the previous response to fetch the next page. - [Rotate the signing secret](https://sendmux.ai/docs/api/webhooks/rotate-the-signing-secret.md): Generates a fresh signing secret and returns it ONCE. The old secret is immediately invalidated — the next event delivery is signed with the new secret. Store the new value securely; it cannot be retrieved later. - [Send a synthetic test event](https://sendmux.ai/docs/api/webhooks/send-a-synthetic-test-event.md): Publishes a synthetic `sendmux.test` event to this webhook subscription. The subscription must include `"sendmux.test"` in `event_types`, and mailbox filters do not block the test delivery. Returns the generated `event_id` so you can correlate the `X-Sendmux-Event-Id` header on your endpoint. - [Update a webhook subscription](https://sendmux.ai/docs/api/webhooks/update-a-webhook-subscription.md): Updates the URL, event types, or enabled flag. Any field omitted from the request body is left unchanged. The signing secret is unaffected — use `POST /webhooks/{id}/rotate-secret` to rotate it. - [Account settings](https://sendmux.ai/docs/guides/account-settings.md): Update your profile, review active sessions, change your password, and manage passkeys. - [API keys](https://sendmux.ai/docs/guides/api-keys.md): Create, scope, rotate, and revoke Sendmux API keys. - [Attachments](https://sendmux.ai/docs/guides/attachments.md): Attach files to Sendmux HTTP send requests. - [Billing](https://sendmux.ai/docs/guides/billing.md): Top up team balance, configure auto top-up, set low-balance alerts, and review transactions. - [Dashboard and logs](https://sendmux.ai/docs/guides/dashboard-logs.md): Monitor sending activity, filter delivery logs, and export log data. - [Deliverability](https://sendmux.ai/docs/guides/deliverability.md): Use deliverability views to monitor bounce rates, complaint rates, and provider health. - [Delivery groups](https://sendmux.ai/docs/guides/delivery-groups.md): Group sending providers and route selected keys or mailboxes through them. - [Domains](https://sendmux.ai/docs/guides/domain-management.md): Add, verify, and manage custom domains for Sendmux mailboxes. - [Domain settings](https://sendmux.ai/docs/guides/domain-settings.md): Understand the coming-soon domain settings shown on domain detail pages. - [HTTP provider](https://sendmux.ai/docs/guides/http-provider.md): What the coming-soon HTTP provider option means in Accounts. - [Idempotency](https://sendmux.ai/docs/guides/idempotency.md): Use the Idempotency-Key header to make mutating requests safe to retry. - [Mailbox push delivery](https://sendmux.ai/docs/guides/mailbox-push-delivery.md): Understand the coming-soon push URL option shown when creating a mailbox. - [Mailboxes](https://sendmux.ai/docs/guides/mailboxes.md): Create mailboxes, manage passwords, set sender identity, and control inbound sender rules. - [AI integrations](https://sendmux.ai/docs/guides/mcp.md): Connect AI tools to Sendmux documentation and product tools. - [Postman collections](https://sendmux.ai/docs/guides/postman-collection.md): Import Sendmux API collections into Postman and configure your API key. - [Quickstart](https://sendmux.ai/docs/guides/quickstart.md): Create a team, add a mailbox, send a test email, and watch the result in Sendmux. - [Sending accounts](https://sendmux.ai/docs/guides/sending-accounts.md): Use the managed sending account, connect your own providers, and test account health. - [Sending by HTTP](https://sendmux.ai/docs/guides/sending-via-http.md): Send single or batch email requests through the Sendmux Sending API. - [Sending via SMTP](https://sendmux.ai/docs/guides/sending-via-smtp.md): Connect an SMTP-compatible app or mail client to Sendmux. - [Team limits](https://sendmux.ai/docs/guides/team-limits.md): Default Sendmux team limits, when increase requests appear, and what happens at the hard limit. - [Teams and access](https://sendmux.ai/docs/guides/teams-access.md): Create teams, invite members, assign roles, and schedule team deletion. - [Webhook replay](https://sendmux.ai/docs/guides/webhook-replay.md): Understand the coming-soon replay action on webhook delivery attempts. - [Webhooks setup](https://sendmux.ai/docs/guides/webhooks-setup.md): Subscribe to Sendmux events, verify signatures, and review delivery attempts. - [Verify webhook signatures](https://sendmux.ai/docs/guides/webhooks-verify-signatures.md): Verify the HMAC-SHA256 signature on every Sendmux webhook delivery. - [Welcome to Sendmux](https://sendmux.ai/docs/index.md): Learn what Sendmux does, where to start, and which guides or API references to use next. - [Errors](https://sendmux.ai/docs/mailbox-api/errors.md): Error codes and handling for the Sendmux Mailbox API. - [Introduction](https://sendmux.ai/docs/mailbox-api/introduction.md): Mailbox-scoped API endpoints for Sendmux mailbox credentials and connected apps. - [Errors](https://sendmux.ai/docs/sending-api/errors.md): Error codes and handling for the Sendmux Sending API. - [Introduction](https://sendmux.ai/docs/sending-api/introduction.md): Send emails programmatically via the Sendmux Sending API. ## OpenAPI Specs - [openapi-app](https://sendmux.ai/docs/openapi-app.json) - [openapi](https://app.sendmux.ai/api/v1/openapi.json) - [openapi-sending](https://sendmux.ai/docs/openapi-sending.json) ## Optional - [App](https://app.sendmux.ai) - [Website](https://sendmux.ai)