> ## Documentation Index > Fetch the complete documentation index at: https://docs.thinnest.ai/llms.txt > Use this file to discover all available pages before exploring further. # List Conversation Messages > One conversation's messages, newest first: the customer's, your agent's, and replies a teammate sent from the inbox (`author: "teammate"`). Your team's internal notes are left out. Photos, voice notes, videos and documents a customer sent come back as links valid for **eight hours** — download what you need to keep. ## OpenAPI ````yaml /api-reference/openapi.json get /conversations/{id}/messages openapi: 3.1.0 info: title: ThinnestAI API version: 1.0.0 description: >- Build voice and WhatsApp agents, place calls, message customers and run a platform of your own customers on one API. servers: - url: https://app.thinnest.ai/api/v1 description: Production security: - bearerAuth: [] tags: - name: Agents description: >- An agent is one assistant with its instructions, model, languages, website widget and call settings — the same thing the console's Agent page builds. Create one here, then give it knowledge, actions and channels. - name: Knowledge description: >- The documents an agent searches and cites when it answers — a web page or pasted text, split into passages and indexed. Use it for facts (prices, policies, opening hours) rather than putting them in the instructions. - name: Actions description: >- Calls to your own HTTPS API that an agent can make mid-conversation, with arguments it fills from what the customer said — how an agent uses data that stays in your own system. Create one, test it, then switch it on. - name: Tools description: >- Everything else an agent can do besides answer: its built-in tools, the MCP tool servers it is connected to, and the accounts it works in (calendar, spreadsheets, CRMs, records kept here, helpdesks). Every tool starts off. - name: Channels description: >- Where an agent answers: the website widget, WhatsApp, Telegram and calls. Read an agent's channels here and connect a Telegram bot; WhatsApp is connected in the console, because Meta's sign-up runs in the business owner's own browser. - name: Calls description: >- A call is one phone, web or WhatsApp conversation with an agent — one you placed through the API, a campaign's, or one a customer made to you. Place calls here, one at a time or in a batch, and read each one back with its summary, collected details and transcript. - name: Post-call description: >- What happens after a call ends: the outcome, a short summary and the details the agent collects. Read a call's analysis here, and set what an agent does after every call. - name: Recordings description: >- A call's audio, for agents that record their calls. Fetch it with your key, or hand a CRM user the signed link a call report carries — that one needs no key. - name: Conversations description: >- A conversation is one customer's thread with your workspace on one channel — WhatsApp, the web widget, Telegram, voice or email. Read threads and their messages (including to catch up on a webhook you missed), answer a WhatsApp customer from your own agent platform, and resolve, take over or assign threads as the inbox does. - name: Messages description: >- Send one approved WhatsApp template to one customer, because something happened in your own system — an order confirmation, a delivery update, an appointment reminder. No agent is needed: this is how your software starts a WhatsApp conversation. - name: One-time codes description: >- Deliver a login or verification code you generated over WhatsApp, without handling templates yourself, and set up the authentication templates it sends with. WhatsApp writes these messages — "*394812* is your verification code." — so you choose only the expiry, the security line and the button. - name: Contacts description: >- The people your workspace knows — kept in step with your CRM by phone number and your own `externalId`, with marketing consent recorded alongside where it came from. - name: Do not call description: >- Numbers your agents must never ring. Every outbound call refuses a number on this list — Create Call answers `409`, a batch refuses that entry, a calling campaign skips the person and records why, and a booked callback is given up — while inbound calls from it are answered as usual. The same list as **Contacts → Do not contact** in the console, and the one your voice agent adds to on its own when a caller asks not to be called again (in any language), which also sends the `contact.opted_out` webhook event. - name: Events description: >- Tell us something happened in your system — `order.delivered`, `trial.ended` — and the sequences and tags you set up in the console decide what follows. Your code says what happened; the console says what happens next. - name: Templates description: >- WhatsApp message templates: the pre-approved messages your business may send to a customer first, or outside the 24 hours after they last wrote. A template is saved as a draft, sent to WhatsApp for review, and can be sent (Send Message, Create Campaign) only once it is `approved`. Templates are named, not numbered, and one name can exist in several languages. - name: Campaigns description: >- A campaign sends one thing to many people. It is either a WhatsApp **broadcast** (`kind: "whatsapp"`), which sends one approved template to everyone in its audience, or a **calling campaign** (`kind: "voice"`), where an agent phones each person from its own number within the hours you set. Who is in the audience is decided by consent, exactly as in the console, and every campaign is created as a draft that you then launch, schedule, pause, resume or cancel. - name: Sequences description: >- A sequence sends one person several approved WhatsApp templates over days — "your order shipped", then "how was it?" two days later — and stops by itself when they reply, are tagged, or an event says so. People join by tag, by event, or one at a time through Enrol in Sequence. Sequence ids are bare uuids. - name: Forms description: >- A WhatsApp form is a screen your customer fills in without leaving the chat — a delivery address, an appointment request, a short survey. Build it here, publish it to your own WhatsApp Business Account, then send it from a template's button, an agent, the inbox or Reply to Conversation. - name: Phone numbers description: >- The numbers your agents answer and call from. A workspace holds them two ways: numbers it **rents** here, charged every month from your balance, and numbers it **brings** from its own carrier account, which we never bill. Each number is answered by at most one agent (its line) and may be lent to one agent to call out on. A number is named by the number itself, in any spelling: `918041234567`, `+918041234567` and `%2B918041234567` in a path are the same number. - name: Voices description: >- The voices an agent can speak with, as the console's voice picker lists them. An item's `id` is what an agent's `voice.voice` takes. - name: Voice clones description: >- Your workspace's own cloned voices, made from a short recording with the speaker's consent. A clone is listed with the Studio voices and can be put on an agent like any other voice. - name: Models description: >- The language models an agent can answer with, as the console names them. An item's `id` is what an agent's `model` takes. - name: Bring your own keys description: >- Run your agents on your own provider accounts and pay a flat platform fee instead of our usage rates. Bring all three keys (speech-to-text, LLM, voice): ₹0.02 a chat reply and ₹1 a call minute, all-in. Or bring only your voice key (scope voice): our speech-to-text, model and telephony, a call billed at the voice-only BYOK rate (₹1.50 / $0.02 a minute by default), chat replies as usual. There is no fallback to our providers when one of your keys fails. - name: Webhooks description: >- Endpoints an agent's events are sent to as they happen — a CRM, a sheet, Slack, Zapier, or a helpdesk email address. Each delivery is a signed JSON `POST` of `{ "id", "event", "sentAt", "data" }`. **Headers on every attempt** | Header | What it is | |---|---| | `x-thinnest-signature` | `sha256=` under the endpoint's signing secret. | | `x-thinnest-signature-v2` | `sha256=.">` — the delivery time, signed. | | `x-thinnest-delivered-at` | When this attempt left (ISO 8601). | | `x-thinnest-event-id` | `evt_…`, the same as the body's `id` — stable across every retry and re-send. | | `x-thinnest-attempt` | `1` for the first attempt, then `2`, `3`, … | **Retries.** A delivery that fails — any answer other than 2xx, a timeout after 10 seconds, or an address we cannot reach — is tried again after 1 minute, 5 minutes, 30 minutes, 2 hours and 6 hours (six attempts over about 8½ hours). Every attempt sends the **same bytes**, so `sentAt` is when the event happened, not when the attempt left. Payloads are kept for 7 days; within that time any failed delivery can be sent again with Redeliver Webhook Events. **Dedupe** on `x-thinnest-event-id` (or the body's `id`): a retry after a timeout can reach you after you already processed the first attempt. Answer 2xx quickly and do the work afterwards. **Freshness.** To refuse replayed requests, verify `x-thinnest-signature-v2` and reject an `x-thinnest-delivered-at` more than five minutes from your clock. Do not check freshness on `sentAt`: a retry's `sentAt` is hours old by design. **Switch-off.** An endpoint is switched off after five events in a row that each failed every attempt — single failed attempts that later succeed do not count. Events that happen while it is off are recorded as not sent; switch it back on and re-send them. The events an endpoint can subscribe to: | Event | When it fires | |---|---| | `lead.captured` | The agent collected a name, email or phone from somebody who showed real interest. | | `conversation.escalated` | The agent handed a conversation to a person — asked for, or because it could not answer. | | `conversation.resolved` | A teammate marked a conversation done; `data.conversationId` is its `conv_…` id, as Get Conversation takes it. | | `call.completed` | A call the agent placed or answered ended — how it ended and how long it lasted, sent the moment it ends. | | `call.analysed` | A call's results are ready: its summary, the details it collected, the transcript, a recording link and what the call cost (`costMicro`, `currency`) — the same shape as Get Call. | | `campaign.finished` | Every person on a broadcast or a calling campaign has been reached, or given up on. | | `contact.opted_out` | During a call, somebody asked not to be called again; their number (`data.phone`) is now on the do-not-call list. | - name: Usage description: >- Read what your workspace used and spent — replies, calls, WhatsApp, the balance history and invoices — the same figures as the console's Usage and Billing pages. All reads. - name: Analytics description: >- The Dashboard's counts and each agent's Analytics page, for building a dashboard of your own that agrees with the console. - name: Customers description: >- Workspaces you create for your own customers when you build a product on this API. Each customer has its own agents, contacts, knowledge, phone numbers and WhatsApp; your one key reaches any of them by adding `Thinnest-Workspace: ` to a request, and everything they use is charged to you. Manage customers from your own workspace, without that header. - name: Workspace description: >- Your workspace's own settings — its name and time zone — as Settings → General shows them. With `Thinnest-Workspace`, the customer's workspace instead. - name: Projects description: >- Projects group a workspace's agents, and are what a team's access is scoped by. Every workspace has a default project that cannot be deleted; a second project needs a plan with teams and projects. - name: Teams description: >- Teams are groups of members and the projects they can reach. A project granted to no team is open to the whole workspace; granting it to a team restricts it to that team's members (owners and admins always see everything), and removing its last grant opens it up again. - name: Members description: >- The people in your workspace and their roles. An API key acts as an admin, never an owner: it can make people admins or members and remove them, but cannot make anybody an owner, and the last owner can be neither demoted nor removed. - name: Invitations description: >- Invitations to join your workspace, as Settings → Members sends them: an email with a link that works for 14 days. Pending invitations count towards your plan's seats. - name: Notifications description: >- What each kind of notification does in your workspace: shown in the console's feed or muted, and whether it is emailed through the email sender you connected in the console. - name: Saved replies description: >- Sentences your team sends often, offered in the inbox composer as `/shortcut`. paths: /conversations/{id}/messages: get: tags: - Conversations summary: List Conversation Messages description: >- One conversation's messages, newest first: the customer's, your agent's, and replies a teammate sent from the inbox (`author: "teammate"`). Your team's internal notes are left out. Photos, voice notes, videos and documents a customer sent come back as links valid for **eight hours** — download what you need to keep. operationId: listConversationMessages parameters: - name: id in: path required: true description: >- The conversation's id (`conv_…`), as the list and the `message.received` webhook give it. schema: type: string example: conv_8d41f2a7-3c6e-4b19-9f05-6a2e7c1d4b83 - name: since in: query required: false description: ISO 8601 date and time. Keeps messages written after this moment. schema: type: string format: date-time example: '2026-10-06T09:00:00Z' - $ref: '#/components/parameters/Limit' - $ref: '#/components/parameters/Cursor' - $ref: '#/components/parameters/Workspace' responses: '200': description: A page of messages. content: application/json: schema: $ref: '#/components/schemas/ConversationMessageList' example: items: - id: msg_6f2a9d4c-1e8b-4c73-a5d0-3b9e7f2c8a16 author: agent parts: - type: text text: >- Sorry about that, Priya. I have raised a replacement for order #10432 — it ships tomorrow. createdAt: '2026-10-06T10:15:09.220Z' - id: msg_0c3e7a9b-5d1f-4e82-b6a4-8f2d1c9e7b50 author: customer parts: - type: text text: The box arrived damaged - type: image url: >- https://storage.example.com/media/conv_8d41f2a7/photo.jpg?token=eyJhbGciOi alt: '' createdAt: '2026-10-06T10:15:01.482Z' nextCursor: null '400': description: '`since`, `limit` or `cursor` is not valid.' content: application/json: schema: $ref: '#/components/schemas/Error' example: error: '`since` must be an ISO 8601 date and time.' '401': $ref: '#/components/responses/Unauthorized' '404': description: No such conversation in this workspace. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Conversation was not found. '429': $ref: '#/components/responses/TooManyRequests' components: parameters: Limit: name: limit in: query required: false description: How many items to return, 1 to 100. schema: type: integer minimum: 1 maximum: 100 default: 25 Cursor: name: cursor in: query required: false description: >- The `nextCursor` from the previous page. Leave it out for the first page. schema: type: string Workspace: name: Thinnest-Workspace in: header required: false description: >- Developers only: the customer workspace this request acts in — its `org_…` id from `POST /customers`. Leave it out to act in your own workspace. schema: type: string example: org_3fKq9TzQ1mN8vB2xR7cLpA schemas: ConversationMessageList: type: object required: - items - nextCursor properties: items: type: array items: $ref: '#/components/schemas/ConversationMessage' nextCursor: type: - string - 'null' description: Pass as `cursor` for the next page. Null on the last page. Error: type: object required: - error properties: error: type: string description: What went wrong, in a sentence you can show a person. example: error: That agent was not found. ConversationMessage: type: object required: - id - author - parts - createdAt properties: id: type: string description: >- The message's id (`msg_…`) — the `messageId` a `message.received` delivery carries, so you can skip ones you already handled. example: msg_0c3e7a9b-5d1f-4e82-b6a4-8f2d1c9e7b50 author: type: string enum: - customer - agent - teammate description: >- Who wrote it: the customer, your agent (ours or your own platform's replies), or a teammate from the inbox. parts: type: array description: The message's content, in order. Most messages are one `text` part. items: $ref: '#/components/schemas/ConversationMessagePart' createdAt: type: string format: date-time description: When it was written. ConversationMessagePart: description: One piece of a message, by `type`. oneOf: - $ref: '#/components/schemas/ConversationTextPart' - $ref: '#/components/schemas/ConversationImagePart' - $ref: '#/components/schemas/ConversationAudioPart' - $ref: '#/components/schemas/ConversationVideoPart' - $ref: '#/components/schemas/ConversationFilePart' - $ref: '#/components/schemas/ConversationLinkPart' - $ref: '#/components/schemas/ConversationCardPart' - $ref: '#/components/schemas/ConversationCarouselPart' - $ref: '#/components/schemas/ConversationChoicesPart' - $ref: '#/components/schemas/ConversationSlotsPart' - $ref: '#/components/schemas/ConversationFormPart' - $ref: '#/components/schemas/ConversationProductsPart' discriminator: propertyName: type mapping: text: '#/components/schemas/ConversationTextPart' image: '#/components/schemas/ConversationImagePart' audio: '#/components/schemas/ConversationAudioPart' video: '#/components/schemas/ConversationVideoPart' file: '#/components/schemas/ConversationFilePart' link: '#/components/schemas/ConversationLinkPart' card: '#/components/schemas/ConversationCardPart' carousel: '#/components/schemas/ConversationCarouselPart' choices: '#/components/schemas/ConversationChoicesPart' slots: '#/components/schemas/ConversationSlotsPart' form: '#/components/schemas/ConversationFormPart' products: '#/components/schemas/ConversationProductsPart' ConversationTextPart: type: object title: Text required: - type - text properties: type: type: string const: text text: type: string description: The words. ConversationImagePart: type: object title: Image required: - type - url - alt properties: type: type: string const: image url: type: string format: uri description: >- The picture. A file a customer sent is a signed link valid for eight hours. alt: type: string description: A description or caption. Often empty for a customer's photo. ConversationAudioPart: type: object title: Audio required: - type - url properties: type: type: string const: audio url: type: string format: uri description: >- The voice note or recording. A signed link valid for eight hours when stored by us. transcript: type: string description: What was said, once transcribed. durationSeconds: type: number description: Length in seconds, when known. ConversationVideoPart: type: object title: Video required: - type - url - alt properties: type: type: string const: video url: type: string format: uri description: The video. A signed link valid for eight hours when stored by us. alt: type: string description: What is in it, or its caption. posterUrl: type: string format: uri description: A still shown before playback, when there is one. mimeType: type: string description: e.g. `video/mp4`. durationSeconds: type: number description: Length in seconds, when known. sizeBytes: type: integer description: Size in bytes, when known. ConversationFilePart: type: object title: File required: - type - url - name properties: type: type: string const: file url: type: string format: uri description: The document. A signed link valid for eight hours when stored by us. name: type: string description: The file's name, e.g. `invoice-10432.pdf`. mimeType: type: string description: e.g. `application/pdf`. sizeBytes: type: integer description: Size in bytes, when known. ConversationLinkPart: type: object title: Link button required: - type - text - url - label properties: type: type: string const: link text: type: string description: The message the button sits under. url: type: string format: uri description: Where the button goes. label: type: string description: The button's words, e.g. "Book a table". ConversationCardPart: type: object title: Card required: - type - title properties: type: type: string const: card title: type: string description: The card's heading. subtitle: type: string description: A line under the heading. imageUrl: type: string format: uri description: The card's picture. actions: type: array description: Buttons on the card. items: $ref: '#/components/schemas/ConversationChoiceOption' ConversationCarouselPart: type: object title: Carousel required: - type - items properties: type: type: string const: carousel items: type: array description: The cards, in order. Each has the fields of a `card` part. items: type: object required: - title properties: type: type: string const: card title: type: string description: The card's heading. subtitle: type: string description: A line under the heading. imageUrl: type: string format: uri description: The card's picture. actions: type: array description: Buttons on the card. items: $ref: '#/components/schemas/ConversationChoiceOption' ConversationChoicesPart: type: object title: Choices required: - type - prompt - options properties: type: type: string const: choices prompt: type: string description: The question. options: type: array description: The answers offered. items: $ref: '#/components/schemas/ConversationChoiceOption' ConversationSlotsPart: type: object title: Time slots required: - type - prompt - slots properties: type: type: string const: slots prompt: type: string description: The question. slots: type: array description: The times offered, as ISO 8601 instants. items: type: string format: date-time ConversationFormPart: type: object title: Inline form required: - type - prompt - fields properties: type: type: string const: form prompt: type: string description: What the form asks for. fields: type: array description: The boxes to fill in. items: type: object required: - name - label - kind - required properties: name: type: string description: The key the answer comes back under. label: type: string description: What the customer reads. kind: type: string enum: - text - email - tel description: The kind of box. required: type: boolean description: Whether it must be filled in. ConversationProductsPart: type: object title: Products required: - type - caption - catalogId - productIds properties: type: type: string const: products caption: type: string description: The words around the products. catalogId: type: string description: The WhatsApp catalogue's id, digits only. productIds: type: array description: >- Your own SKUs. Empty opens the whole catalogue, one shows that product, several show a picker. items: type: string sectionTitle: type: string description: The picker's heading, when several products are named. ConversationChoiceOption: type: object required: - id - label properties: id: type: string description: Stable identifier sent back when chosen. label: type: string description: What the customer sees. responses: Unauthorized: description: The key is missing, wrong or revoked. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: 'Send a valid API key as `Authorization: Bearer `.' TooManyRequests: description: Over the per-minute limit. Wait for `Retry-After` seconds. headers: Retry-After: schema: type: integer description: Seconds to wait. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Over 240 requests a minute. Slow down and retry. securitySchemes: bearerAuth: type: http scheme: bearer description: >- Your API key (`ta_live_…`) from **Settings → API keys**, sent as `Authorization: Bearer `. Keep it on a server: it can message every customer you have. A key is full, build or read-only; a request its level does not allow is refused with `403`. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.