# Tychron Atlas Documentation

> docs.tychron.com is the developer documentation for Tychron Corporation, a licensed U.S. communications carrier. It covers Tychron's carrier-grade HTTP APIs for business messaging (SMS, MMS) and number intelligence (CNAM, LRN/eLRN, MCL), plus the Atlas API & provisioning reference for programmatic number ordering, TCR brand/campaign registration, webhook event subscriptions, and opt-out list management. Machine-readable OpenAPI 3 specifications are published for every messaging and data API. Commercial overview, rates, and sales: https://www.tychron.com/ (site map for machines: https://www.tychron.com/llms.txt).

## Start here

- [Documentation home](https://docs.tychron.com/): what each API does and where to find it
- [Atlas API & Provisioning Reference](https://docs.tychron.com/api-reference/): the full chaptered reference — authentication, number ordering and configuration, TCR brand and campaign registration, campaign-number assignment, CSP campaign sharing, webhook event subscriptions, opt-out lists, and account operations. Each chapter is deep-linkable from this index.

## SMS API

- [SMS API overview](https://docs.tychron.com/sms-api/): capabilities, authentication, and endpoints
- [Sending SMS via HTTP](https://docs.tychron.com/sms-api/sending-sms-via-http/): request format, long-message segmentation, response codes
- [Receiving SMS via HTTP](https://docs.tychron.com/sms-api/receiving-sms-via-http/): inbound message webhooks
- [Sending SMS DLR via HTTP](https://docs.tychron.com/sms-api/sending-sms-dlr-via-http/): delivery receipts you send
- [Receiving SMS DLR via HTTP](https://docs.tychron.com/sms-api/receiving-sms-dlr-via-http/): delivery-receipt webhooks. Contract note: the send request opts in with request_delivery_report and carries NO callback URL — Tychron posts the report to the HTTP endpoint configured on the sending number's SMS-enabled Switch (see the Switches chapter of the Atlas reference). That ONE endpoint receives both inbound messages (type "sms") and delivery reports (type "sms_dlr") — receivers dispatch on the type field.
- [SMS OpenAPI spec](https://docs.tychron.com/openapi/sms.openapi.yaml) (all specs: https://docs.tychron.com/openapi/)

## MMS API

- [MMS API overview](https://docs.tychron.com/mms-api/): media messaging capabilities and endpoints
- [Sending MMS via HTTP](https://docs.tychron.com/mms-api/sending-mms-via-http/)
- [Receiving MMS via HTTP](https://docs.tychron.com/mms-api/receiving-mms-via-http/)
- [Receiving MMS DLR via HTTP](https://docs.tychron.com/mms-api/receiving-mms-dlr-via-http/): delivery-receipt webhooks. Same contract as SMS: request_delivery_report: true in the send request, no callback URL — the report is posted to the endpoint configured on the MMS-enabled Switch, the same endpoint that receives inbound MMS. Dispatch on the kind field: mms_forward_req = inbound message, mms_delivery_report_req = delivery report.
- [MMS OpenAPI spec](https://docs.tychron.com/openapi/mms.openapi.yaml)

## Number-intelligence APIs

- [CNAM API](https://docs.tychron.com/cnam-api/): caller-ID name lookups with robocall status included
- [CNAM OpenAPI spec](https://docs.tychron.com/openapi/cnam.openapi.yaml)
- [LRN API](https://docs.tychron.com/lrn-api/): LRN/eLRN lookups — a number's real routing carrier plus State, City, ZIP, Rate Center, LATA, and OCN
- [LRN OpenAPI spec](https://docs.tychron.com/openapi/lrn.openapi.yaml)
- [MCL API](https://docs.tychron.com/mcl-api/): messaging carrier lookup — a number's messaging carrier and whether it is text-enabled
- [MCL OpenAPI spec](https://docs.tychron.com/openapi/mcl.openapi.yaml)

## Atlas API & Provisioning Reference chapters

Every chapter of the reference, in reading order, with its main sections:

- [Introduction](https://docs.tychron.com/api-reference/introduction/) (Markdown: https://docs.tychron.com/api-reference/introduction.md)
- [Your Resources](https://docs.tychron.com/api-reference/your-resources/): Account, DID, Switch, Messaging Auto Responses, Role, User, API Key, Bulk Dip Tasks, … (Markdown: https://docs.tychron.com/api-reference/your-resources.md)
- [API](https://docs.tychron.com/api-reference/api/): Pagination Parameters, Common Parameters, Paths (Markdown: https://docs.tychron.com/api-reference/api.md)
- [Number Inventory](https://docs.tychron.com/api-reference/number-inventory/) (Markdown: https://docs.tychron.com/api-reference/number-inventory.md)
- [Ordering System Reference](https://docs.tychron.com/api-reference/ordering-system-reference/): Ordering Overview, Carts (Markdown: https://docs.tychron.com/api-reference/ordering-system-reference.md)
- [Cart Requests](https://docs.tychron.com/api-reference/cart-requests/): Schema, API, Request Types (Markdown: https://docs.tychron.com/api-reference/cart-requests.md)
- [Cart Request Documents](https://docs.tychron.com/api-reference/cart-request-documents/): Schema, API (Markdown: https://docs.tychron.com/api-reference/cart-request-documents.md)
- [Orders](https://docs.tychron.com/api-reference/orders/): Schema, API (Markdown: https://docs.tychron.com/api-reference/orders.md)
- [Requests](https://docs.tychron.com/api-reference/requests/): Schema, API, Request Types (Markdown: https://docs.tychron.com/api-reference/requests.md)
- [Request Documents](https://docs.tychron.com/api-reference/request-documents/): Schema, API (Markdown: https://docs.tychron.com/api-reference/request-documents.md)
- [Request Provision Records](https://docs.tychron.com/api-reference/request-provision-records/): Schema, API (Markdown: https://docs.tychron.com/api-reference/request-provision-records.md)
- [Roles](https://docs.tychron.com/api-reference/roles/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/roles.md)
- [Users](https://docs.tychron.com/api-reference/users/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/users.md)
- [API Keys](https://docs.tychron.com/api-reference/api-keys/): Schema, Summary, Where are my secrets?, API (Markdown: https://docs.tychron.com/api-reference/api-keys.md)
- [Bulk Dip Tasks](https://docs.tychron.com/api-reference/bulk-dip-tasks/): Schema, Summary, API, Webhook Integration (Markdown: https://docs.tychron.com/api-reference/bulk-dip-tasks.md)
- [Call Data Webhooks](https://docs.tychron.com/api-reference/call-data-webhooks/): Schema, Summary, API, Webhook (Markdown: https://docs.tychron.com/api-reference/call-data-webhooks.md)
- [Secret Keys](https://docs.tychron.com/api-reference/secret-keys/): Schema, Summary, Where are my secrets?, API (Markdown: https://docs.tychron.com/api-reference/secret-keys.md)
- [Switches](https://docs.tychron.com/api-reference/switches/): Schema, Summary, API, Components (Markdown: https://docs.tychron.com/api-reference/switches.md)
- [Messaging Auto Responses](https://docs.tychron.com/api-reference/messaging-auto-responses/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/messaging-auto-responses.md)
- [DIDs](https://docs.tychron.com/api-reference/dids/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/dids.md)
- [Number Management](https://docs.tychron.com/api-reference/number-management/): Toggling MMS on an existing number (Markdown: https://docs.tychron.com/api-reference/number-management.md)
- [DID Destinations](https://docs.tychron.com/api-reference/did-destinations/): Schema, Summary, Types, API (Markdown: https://docs.tychron.com/api-reference/did-destinations.md)
- [DID - Optout Items](https://docs.tychron.com/api-reference/did-optout-items/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/did-optout-items.md)
- [OSR Overwrite Requests](https://docs.tychron.com/api-reference/osr-overwrite-requests/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/osr-overwrite-requests.md)
- [CSP Enums](https://docs.tychron.com/api-reference/csp-enums/): Schemas, API (Markdown: https://docs.tychron.com/api-reference/csp-enums.md)
- [CSP Brands](https://docs.tychron.com/api-reference/csp-brands/): Schema, API (Markdown: https://docs.tychron.com/api-reference/csp-brands.md)
- [CSP Campaigns](https://docs.tychron.com/api-reference/csp-campaigns/): Schema, API (Markdown: https://docs.tychron.com/api-reference/csp-campaigns.md)
- [CSP - Campaign - Optout Items](https://docs.tychron.com/api-reference/csp-campaign-optout-items/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/csp-campaign-optout-items.md)
- [Shared Resource Groups](https://docs.tychron.com/api-reference/shared-resource-groups/): Schema, Summary, API, Shared Resource Groups - Notes (Markdown: https://docs.tychron.com/api-reference/shared-resource-groups.md)
- [Event Subscriptions](https://docs.tychron.com/api-reference/event-subscriptions/): Schema, Summary, API (Markdown: https://docs.tychron.com/api-reference/event-subscriptions.md)
- [Events](https://docs.tychron.com/api-reference/events/): Schema, Request, Types (Markdown: https://docs.tychron.com/api-reference/events.md)
- [SMPP](https://docs.tychron.com/api-reference/smpp/): Supported TLVs (Markdown: https://docs.tychron.com/api-reference/smpp.md)
- [Schemas](https://docs.tychron.com/api-reference/schemas/): Schema / AddonsData, Schema / ApiKey, Schema / ApiKeyResponse, Schema / ApiKeysResponse, Schema / AttachSwitchMmsEncryptionKeyData, Schema / AttachSwitchMmsEncryptionKeyRequest, Schema / AttachSwitchMmsSigningKeyData, Schema / AttachSwitchMmsSigningKeyRequest, … (Markdown: https://docs.tychron.com/api-reference/schemas.md)
- [End notes](https://docs.tychron.com/api-reference/end-notes/) (Markdown: https://docs.tychron.com/api-reference/end-notes.md)
- [Changelog](https://docs.tychron.com/api-reference/changelog/): 2026-07-29, 2026-07-06, 2026-05-20, 2025-09-21, 2025-04-15, 2024-10-22, 2024-10-04, 2023-05-23, … (Markdown: https://docs.tychron.com/api-reference/changelog.md)

## For AI assistants and coding agents

- [llms-full.txt](https://docs.tychron.com/llms-full.txt): the complete Atlas API & Provisioning Reference as one Markdown file (every chapter, endpoint, schema and example), for ingestion in a single fetch. Each chapter is also available on its own as Markdown at the .md URL listed above.
- [OpenAPI specifications](https://docs.tychron.com/openapi/): the live Atlas API & Provisioning spec (https://api.atlas.tychron.online/api/v1/openapi, JSON, always current — the chaptered reference is generated from it) and the SMS, MMS, CNAM, LRN and MCL specs (YAML) — use those for typed clients and request validation.
- [Using these docs with an AI assistant](https://docs.tychron.com/#ai-assistant): what to point an assistant at, and a starter prompt.

## Optional

- [Privacy policy](https://docs.tychron.com/privacy-policy/)
- [Tychron main site](https://www.tychron.com/): services, pricing, carrier surcharge schedules, and compliance guides
- [Tychron system status](https://status.tychron.com/)