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# Postscript API and MCP server

> Postscript has an API and an official MCP server, but neither builds or sends campaigns (checked 23 Oct 2026). The MCP server is read-only: it pulls campaign, automation, popup and shop-wide analytics on Pro and Enterprise plans and "cannot create, edit, send, or delete anything". The API reference lists subscriber reads and updates, unsubscribe, redact and custom events.

SMS marketing platform for Shopify stores: campaign and automation flows, segments, keywords and popups for list growth, and two-way Conversations with subscribers.

## What is the Postscript API?

Cotlet's Postscript API exposes 13 endpoints for your own Postscript account: list segments, list campaigns, get message analytics, list keywords, find subscriber, list conversations, create segment, create campaign draft, send preview, schedule or launch campaign, stop campaign, create keyword and reply to conversation. The list_segments endpoint returns segments of the shop from Messaging > Segments, with their Segment Size. Each endpoint takes simple JSON inputs like search, campaign_id or name and works both as an operation of the postscript_read or postscript_write MCP tool for agents and as a REST call for scripts.

- **Category:** [Marketing & SEO](https://cotlet.dev/integrations/category/marketing-seo.md)
- **Endpoints:** 13 (6 read, 7 write)
- **Updated:** 2026-10-23

Postscript has an API and an official MCP server, but neither builds or sends campaigns (checked 23 Oct 2026). Cotlet is a hosted MCP server and REST API for Postscript with 13 endpoints (6 read, 7 write): you sign in once in your own cloud browser, your AI agent does the work.

## Does Postscript have an official API?

Postscript has an API and an official MCP server, but neither builds or sends campaigns (checked 23 Oct 2026). The MCP server is read-only: it pulls campaign, automation, popup and shop-wide analytics on Pro and Enterprise plans and "cannot create, edit, send, or delete anything". The API reference lists subscriber reads and updates, unsubscribe, redact and custom events.

| Task | Postscript official | Cotlet |
|---|---|---|
| Read campaign and automation analytics | Partly: Official MCP reads them on Pro and Enterprise plans only; Message Analytics in the dashboard is on all plans | Yes |
| Find a subscriber | Partly: API has Get Subscribers and Get Subscriber; the Zapier app has Find Subscriber | Yes |
| Create segments | No | Yes |
| Build a campaign flow | No | Yes |
| Schedule, launch or stop a campaign | No | Yes |
| Create keywords | No | Yes |
| Reply in Conversations | Partly: The Zapier app has Send Message and a New Message trigger; the API reference lists no conversation endpoint | Yes |
| Send a preview of a message | No | Yes |

Sources: [Postscript Help: Postscript MCP](https://help.postscript.io/en/articles/17455878-postscript-mcp), [Postscript Developers: API authentication](https://developers.postscript.io/docs/api-authentication), [Postscript Developers: API reference](https://developers.postscript.io/llms.txt), [Postscript on Zapier](https://zapier.com/apps/postscript-1/integrations)

## Quick reference

```text
Postscript has an API and an official MCP server, but neither builds or sends campaigns (checked 23 Oct 2026). The MCP server is read-only: it pulls campaign, automation, popup and shop-wide analytics on Pro and Enterprise plans and "cannot create, edit, send, or delete anything". The API reference lists subscriber reads and updates, unsubscribe, redact and custom events.
Cotlet provides a hosted MCP server and REST API for Postscript: 13 tools (6 read, 7 write).
Access       Sign up at https://cotlet.dev/app/signup?app=postscript, then request the app and create API keys in the Cotlet console.

MCP server   https://cotlet.dev/mcp/v1
MCP tools    postscript_read, postscript_write, reads and writes apart; call one with {"operation": "<operation>", "arguments": {...}}
REST base    https://cotlet.dev/api/v1/postscript, each operation at its own route, e.g. POST /api/v1/postscript/campaigns
Auth         Authorization: Bearer <COTLET_API_KEY>. Listing endpoints and schemas needs no key; calling an endpoint needs one. Over MCP the input schemas come with sign-in.
Operations   list_segments, list_campaigns, get_message_analytics, list_keywords, find_subscriber, list_conversations, create_segment, create_campaign, send_preview, schedule_campaign, stop_campaign, create_keyword, reply_to_conversation
Confirm      send_preview, schedule_campaign, stop_campaign, create_keyword, reply_to_conversation (by default the user approves each call; the user can switch this off per tool, e.g. for scheduled automations)
Markdown     https://cotlet.dev/integrations/postscript-api-mcp-server.md

How access works:
1. The user signs up at https://cotlet.dev/app/signup?app=postscript, requests Postscript in the Cotlet console and creates an API key there.
2. The user signs in to Postscript once in their Cotlet Cloud Browser (their own Chrome in the cloud, opened from the console) and enables Postscript for agents. An agent cannot do this step.
3. The API key goes into the MCP client or the REST call as a bearer token.

Fits: people who want a hosted Postscript server that someone else maintains, including non-developers. Developers who prefer to run and fix code on their own computer can use an open-source Postscript MCP server instead.

Policy: Cotlet never stores passwords, never solves CAPTCHAs, never bypasses MFA.
Company: legal details in the Terms of service at https://cotlet.dev/terms. Contact contact@cotlet.dev.
Sign-in: the user signs in to Postscript in their own Cloud Browser, a Chrome Cotlet runs for them in the EU; password saving is off, the profile is AES-256-GCM encrypted, and agents get Postscript only after the user enables it. Calls are requests from that browser's IP with its cookies, each listed in the user's Background activity. Disable for agents, signing out in the browser or Reset browser cuts access. Cotlet is run by Take Group sp. z o.o. (EU VAT PL6342984273).
API key: holds no Postscript login or cookies, only asks Cotlet to run a tool. Each key is scoped to chosen apps and tools, read only or read and write. Actions that reach other people wait for the user's approval by default, so a leaked key cannot post or message as the user. Every call is in the activity log; deleting the key ends access at once.
Terms: the user stays responsible for following Postscript's terms; Cotlet is not affiliated with Postscript.
```

## What can an AI agent do in Postscript?

Cotlet is best for Shopify store owners and SMS marketers who want their AI agent to build campaign drafts, create keywords and segments, answer subscriber replies and report on campaigns without running or fixing a server.

- **[Build a win-back SMS campaign](https://cotlet.dev/integrations/postscript-api-mcp-server/win-back-campaign.md)** (runs: weekly): "Build a win-back campaign for subscribers who never ordered, never clicked and never replied, opted in over 180 days ago. Save it as a draft, send me a preview and wait for my OK before scheduling." → `list_segments`, `create_segment`, `create_campaign`, `send_preview`, `schedule_campaign`
- **[Launch a VIP keyword campaign](https://cotlet.dev/integrations/postscript-api-mcp-server/vip-keyword-campaign.md)** (runs: weekly): "Create the keyword VIPACCESS with a 15% coupon reply, a segment of everyone who texted it, and a draft campaign to that segment. Do not schedule anything yet." → `list_keywords`, `create_keyword`, `create_segment`, `create_campaign`, `schedule_campaign`
- **[Answer subscriber replies](https://cotlet.dev/integrations/postscript-api-mcp-server/answer-subscriber-replies.md)** (runs: daily): "List unresolved Postscript conversations from the last day, check each subscriber, and reply to shipping questions with a short answer. Leave refunds and angry messages for me." → `list_conversations`, `find_subscriber`, `reply_to_conversation`
- **Weekly SMS performance report** (runs: weekly): "Every Monday, report last week's revenue, orders, unique clicks and unsubscribes for each campaign and rank them by revenue." → `list_campaigns`, `get_message_analytics`

## Can Postscript automations run on a schedule in n8n, Make or Zapier?

Yes. Cotlet does not replace your automation platform: it gives it a Postscript connection it does not have, with the same API key as your agent. Write actions ask for your OK by default; switch that off in your dashboard for the tools you choose, for example to build a win-back sms campaign, and the schedule runs on its own. Cotlet runs in the cloud, so it keeps going while your computer is off.

| Where | How to connect | How to schedule |
|---|---|---|
| Your AI agent | Add https://cotlet.dev/mcp/v1 with your API key. | A scheduled agent run, for example a Claude Code routine. |
| n8n | MCP Client node with https://cotlet.dev/mcp/v1, or an HTTP Request node with the endpoint's method and URL, such as GET https://cotlet.dev/api/v1/postscript/segments. | Schedule Trigger node. |
| Make | HTTP module: the endpoint's method and URL with an Authorization: Bearer header, and a JSON body for POST, PUT and PATCH. | Scenario schedule. |
| Zapier | Webhooks by Zapier, Custom Request: the same method, URL, header and body. | Schedule by Zapier trigger. |
| Your own script | GET https://cotlet.dev/api/v1/postscript/segments with your API key. | cron or GitHub Actions. |

## Tools

**For AI agents:** Every endpoint and its schema is public. The 13 endpoints on this page, with parameters and example responses, can be listed without an account. Calling one returns 401 without an API key and 403 while the key has no access to Postscript.

### list_segments

Segments of the shop from Messaging > Segments, with their Segment Size. Access: read. REST: `GET /api/v1/postscript/segments`. MCP: `postscript_read → list_segments`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `search` | string | no | Only segments whose name contains this text. |

Returns the segments on the Segments page, including the default ones such as All Customers and Subscribers (INTL Included). size is the Segment Size Postscript shows; it refreshes daily for segments used in a campaign in the last 30 days and is otherwise as of the last manual refresh. Unsubscribed people are never counted. Use segment names as include_segments and exclude_segments of create_campaign.

Example response:

```json
{
  "segments": [
    {
      "segment_id": "41872",
      "name": "All Customers and Subscribers (INTL Included)",
      "size": 18240
    },
    {
      "segment_id": "52310",
      "name": "Subscribers with No Orders",
      "size": 5127
    }
  ]
}
```

### list_campaigns

Campaign flows from Messaging > Flow Builder, with status and the segments they include. Access: read. REST: `GET /api/v1/postscript/campaigns`. MCP: `postscript_read → list_campaigns`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `search` | string | no | Only campaigns whose name contains this text. |

Lists the one-time campaign flows in Flow Builder, as the list shows them: name, status and the segments in Include and Exclude.. Use campaign_id with schedule_campaign, send_preview and stop_campaign.

Example response:

```json
{
  "campaigns": [
    {
      "campaign_id": "f_51877",
      "name": "VIP drop",
      "status": "draft",
      "include_segments": [
        "VIPACCESS opt-ins"
      ],
      "exclude_segments": []
    },
    {
      "campaign_id": "f_51702",
      "name": "Restock alert",
      "status": "ended",
      "include_segments": [
        "All Customers and Subscribers (INTL Included)"
      ],
      "exclude_segments": []
    }
  ]
}
```

### get_message_analytics

Message Analytics rows per campaign and automation: sends, clicks, orders, revenue and unsubscribes. Access: read. REST: `GET /api/v1/postscript/message-analytics`. MCP: `postscript_read → get_message_analytics`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `from` | date | no | First day of the range. |
| `to` | date | no | Last day of the range. |
| `group_by` | enum | no | day, week or month.. |
| `sort_by` | string | no | Column to sort by, for example Revenue.. |

Reads Data & Insights > Messages for the date range, one row per message flow with the columns Postscript shows: Messages Sent, Total Clicks, Unique Clicks, Click-Through Rate (CTR), Orders, Revenue, Total Unsubscribes and Unsubscribe %. Postscript updates the data every 15 minutes, and Total Unsubscribes counts only opt-outs attributed to an automation or campaign. To read a calendar month, use its exact first and last day. Works on all Postscript plans.

Example response:

```json
{
  "from": "2026-10-12",
  "to": "2026-10-18",
  "rows": [
    {
      "name": "VIP drop",
      "type": "campaign",
      "messages_sent": 4120,
      "total_clicks": 988,
      "unique_clicks": 802,
      "orders": 37,
      "revenue": 2310,
      "total_unsubscribes": 21,
      "unsubscribe_pct": 0.5
    },
    {
      "name": "Win-back for quiet subscribers",
      "type": "campaign",
      "messages_sent": 3412,
      "total_clicks": 301,
      "unique_clicks": 260,
      "orders": 21,
      "revenue": 1840,
      "total_unsubscribes": 34,
      "unsubscribe_pct": 1
    }
  ]
}
```

### list_keywords

Opt-in keywords from Acquisition > Keywords, with their reply. Access: read. REST: `GET /api/v1/postscript/keywords`. MCP: `postscript_read → list_keywords`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `search` | string | no | Only keywords that contain this text. |

Returns each keyword on the Keywords page with its reply text and coupon, if the reply includes one. Check it before create_keyword: every plan can use keywords, and more than two need the Growth, Professional or Enterprise plan.

Example response:

```json
{
  "keywords": [
    {
      "keyword": "JOIN",
      "reply": "Welcome to Northwind Coffee! Reply STOP to unsubscribe.",
      "coupon": null
    }
  ]
}
```

### find_subscriber

Subscriber profile from Search, found by phone number, name or email. Access: read. REST: `GET /api/v1/postscript/subscribers/find`. MCP: `postscript_read → find_subscriber`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `query` | string | yes | Phone number, name or email. |

Searches Postscript for one subscriber and returns the profile fields Postscript shows under Subscriber Details: status, subscriber ID, how and when they subscribed, tags, the last message sent, messages sent and link clicks. Use it before a reply or a segment to see who the person is.

Example response:

```json
{
  "subscribers": [
    {
      "subscriber_id": "7740215",
      "name": "Dana R.",
      "phone": "+1 555 0142",
      "status": "active",
      "subscribed_via": "keyword JOIN",
      "subscribed_at": "2026-06-02",
      "tags": [
        "vip"
      ],
      "last_message_at": "2026-10-21",
      "messages_sent": 14,
      "link_clicks": 3
    }
  ]
}
```

### list_conversations

Threads from Messaging > Conversations, filterable by state, topic and sentiment. Access: read. REST: `GET /api/v1/postscript/conversations`. MCP: `postscript_read → list_conversations`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `thread_state` | enum | no | all, unresolved or resolved. Default: all. |
| `topic` | string | no | Last Response Topic, for example Shipping or Payment. |
| `sentiment` | enum | no | negative or positive. |

Returns subscriber threads with the last message, the topic Postscript assigned (for example Shipping or Payment) and the sentiment. Filters match the dashboard's Thread State, Last Response Topic and Last Response Sentiment and can be combined. Two-way messaging works for US and Canadian subscribers.

Example response:

```json
{
  "conversations": [
    {
      "conversation_id": "c_90412",
      "subscriber_id": "7740215",
      "subscriber_name": "Dana R.",
      "last_message": "Where is my order?",
      "topic": "Shipping",
      "sentiment": null,
      "thread_state": "unresolved"
    },
    {
      "conversation_id": "c_90377",
      "subscriber_id": "7712968",
      "subscriber_name": "Chris M.",
      "last_message": "I want a refund",
      "topic": "Payment",
      "sentiment": "negative",
      "thread_state": "unresolved"
    }
  ]
}
```

### create_segment

Save a segment under Messaging > Segments from criteria joined with and or or. Access: write. REST: `POST /api/v1/postscript/segments`. MCP: `postscript_write → create_segment`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `name` | string | yes | Segment name. |
| `criteria` | array | yes | List of {criterion, parameter, value, join}. join is and or or, absent on the first item. |
| `include_phone_only` | boolean | no | Include all phone-only subscribers. Default: false. |

Saves a segment from the criteria you give, each as a criterion name from the Segments editor, a parameter such as equals or before last, and a value. join is and or or and links an item to the one before it; the first item has none. Returns the Segment Size Postscript computes. It messages nobody and only saves the definition, so it does not wait for your OK. include_phone_only adds subscribers not yet linked to a Shopify customer, and purchase filters do not apply to them.

Example response:

```json
{
  "segment_id": "60418",
  "name": "Unengaged 180 days",
  "size": 3412,
  "include_phone_only": false
}
```

### create_campaign

Save a campaign flow draft with its segments and first Send Message block. Sends nothing. Access: write. REST: `POST /api/v1/postscript/campaigns`. MCP: `postscript_write → create_campaign`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `name` | string | yes | Campaign name. |
| `include_segments` | array | yes | Segment names to send to. |
| `exclude_segments` | array | no | Segment names to leave out. |
| `exclude_recently_messaged` | boolean | no | Exclude customers messaged in the last 16 hours. Default: false. |
| `cancel_on` | string | no | Cancellation trigger that removes a subscriber from the flow, for example Order Created. |
| `message` | string | yes | Text of the first Send Message block. |

Creates the flow under Messaging > Create Campaign > Create Campaign Flow and saves it with Save Flow, so status is draft. You choose the Include and Exclude segments (up to 10 in total), whether to exclude customers messaged in the last 16 hours, and an optional cancellation trigger such as Order Created. The draft holds one Send Message block. Splits, delays and branch messages you add in Flow Builder. It reaches nobody, so it does not wait for your OK; schedule_campaign does.

Example response:

```json
{
  "campaign_id": "f_51877",
  "name": "VIP drop",
  "status": "draft",
  "include_segments": [
    "VIPACCESS opt-ins"
  ],
  "exclude_recently_messaged": true,
  "cancel_on": "Order Created"
}
```

### send_preview

Text a preview of a campaign message to one phone number. Access: write, asks the user first. REST: `POST /api/v1/postscript/campaigns/{campaign_id}/previews`. MCP: `postscript_write → send_preview`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `campaign_id` | string | yes | Campaign from list_campaigns or create_campaign. |
| `phone` | string | yes | Phone number to text. |

Uses Send Preview next to the message in Flow Builder and the phone number you give. It reaches a real phone and counts as usage, so use your own number. Returns sent once Postscript accepts it. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "campaign_id": "f_51877",
  "phone": "+1 555 0100",
  "status": "sent"
}
```

### schedule_campaign

Activate a campaign flow immediately or at a date and time. Access: write, asks the user first. REST: `POST /api/v1/postscript/campaigns/{campaign_id}/schedule`. MCP: `postscript_write → schedule_campaign`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `campaign_id` | string | yes | Campaign draft to activate. |
| `starts_at` | datetime | no | Date and time to start. Leave out to activate immediately. |
| `use_subscriber_time_zone` | boolean | no | Send at the given time in each subscriber's time zone. Default: false. |

Uses Schedule or Launch: Activate immediately starts the one-time flow now, Activate at a scheduled time and date starts it then. use_subscriber_time_zone sends at that local time in each region and works only for scheduled campaigns. Postscript holds campaign messages until waking hours in each subscriber's time zone. It sends texts to everyone in the Include segments. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "campaign_id": "f_51877",
  "status": "scheduled",
  "starts_at": "2026-10-28T11:00:00",
  "use_subscriber_time_zone": true
}
```

### stop_campaign

End a running campaign flow with End campaign and Stop campaign. Access: write, asks the user first. REST: `POST /api/v1/postscript/campaigns/{campaign_id}/stop`. MCP: `postscript_write → stop_campaign`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `campaign_id` | string | yes | Campaign to stop. |

Ends the flow in Flow Builder. A stopped flow cannot be reactivated, and some messages may still send after you stop it. Returns the status Postscript shows. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "campaign_id": "f_51702",
  "status": "ended"
}
```

### create_keyword

Create an opt-in keyword with a reply, optionally with a coupon. Access: write, asks the user first. REST: `POST /api/v1/postscript/keywords`. MCP: `postscript_write → create_keyword`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `keyword` | string | yes | The word people text, for example VIPACCESS. |
| `reply` | string | no | Reply text sent after opt-in. |
| `coupon_type` | enum | no | percent or amount. Leave out for no coupon. |
| `coupon_value` | number | no | Percent or dollar amount of the coupon. |

Uses Acquisition > Keywords > Create Keyword and Save Keyword. The name is visible to subscribers. With a coupon, Postscript's Include coupon in reply is turned on with a percent or dollar amount; without one, the reply is added as an action. Anyone who texts the word is added to your SMS list and gets the reply, so it reaches people. More than two keywords need the Growth, Professional or Enterprise plan. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "keyword": "VIPACCESS",
  "reply": "You are in! Here is 15% off, a day before the public.",
  "coupon": {
    "type": "percent",
    "value": 15
  }
}
```

### reply_to_conversation

Send a reply in a Conversations thread with Send Reply. Access: write, asks the user first. REST: `POST /api/v1/postscript/conversations/{conversation_id}/replies`. MCP: `postscript_write → reply_to_conversation`.

| Parameter | Type | Required | Description |
|---|---|---|---|
| `conversation_id` | string | yes | Thread from list_conversations. |
| `body` | string | yes | Message text. |

Sends one text message in the thread to the subscriber. It counts as usage, as a campaign would, and works for US and Canadian subscribers. It does not Resolve the thread or Opt Out the subscriber; both stay in the dashboard. By default you confirm each call; you can switch that off for this tool.

Example response:

```json
{
  "conversation_id": "c_90412",
  "status": "sent",
  "body": "Hi Dana, your order shipped on Monday. The tracking link is in your confirmation email. Reply here if it has not arrived by Friday."
}
```

## How do I connect Postscript to Claude Code, Codex or Cursor?

Connecting Postscript takes three steps: sign up, sign in to Postscript once in your Cloud Browser and enable it for agents, then add one MCP server or call the REST API with the same key.

### Connect Postscript to your agent.

1. **Create an account** Sign up and add Postscript in the console. Your API key is there too.

2. **Sign in to Postscript in your Cloud Browser** Open your Cloud Browser in the console: your own Chrome in the cloud. Sign in to Postscript there yourself, the way you always do, then press Enable for agents, read only or read and write. We never save your password, and your agent keeps working even when your computer is off.

3. **Add Cotlet to your agent** Paste the snippet for your client. The same server and key serve every app you connect, so you do this once.

   Claude Code:

```
claude mcp add --transport http cotlet \
  https://cotlet.dev/mcp/v1 \
  --header "Authorization: Bearer $COTLET_API_KEY"
```

   Cursor:

```
{
  "mcpServers": {
    "cotlet": {
      "url": "https://cotlet.dev/mcp/v1",
      "headers": {
        "Authorization": "Bearer ${COTLET_API_KEY}"
      }
    }
  }
}
```

   Codex:

```
# ~/.codex/config.toml
[mcp_servers.cotlet]
url = "https://cotlet.dev/mcp/v1"
bearer_token_env_var = "COTLET_API_KEY"
```

4. **Ask your agent** Ask in plain words. Your agent finds the Postscript tools on the server and calls them for you; anything that reaches other people waits for your OK unless you switch that off for a tool.

```
Build a win-back campaign for subscribers who never ordered, never clicked and never replied, opted in over 180 days ago. Save it as a draft, send me a preview and wait for my OK before scheduling.
```

### Call Postscript from your scripts.

1. **Export your API key** Your scripts use the same API key as your agent. Keep it in an environment variable, never in your code.

```
export COTLET_API_KEY="cotlet_..."
```

2. **Call a tool** Every tool is an endpoint under /api/v1/postscript with its own method and path, listed with the endpoints above. Path parameters go in the URL; the other parameters go in the query for GET and DELETE and in a JSON body otherwise.

```
curl -X POST https://cotlet.dev/api/v1/postscript/campaigns \
  -H "Authorization: Bearer $COTLET_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name":"VIP drop","include_segments":["VIPACCESS opt-ins"],"exclude_recently_messaged":true,"cancel_on":"Order Created","message":"The VIP drop is open. Shop the new roast before anyone else: northwind.example/vip"}'
```

3. **Read the result** You get plain JSON back, ready for your script. A failed call costs nothing.

```
{
  "campaign_id": "f_51877",
  "name": "VIP drop",
  "status": "draft",
  "include_segments": [
    "VIPACCESS opt-ins"
  ],
  "exclude_recently_messaged": true,
  "cancel_on": "Order Created"
}
```

## Why use Cotlet for Postscript?

**Built for agents**

- One MCP server for every app you connect.
- The same tools as a REST API for scripts and cron jobs.
- Works with Claude Code, Codex and Cursor.

**Your login stays yours**

- You sign in to Postscript yourself, in your own Cloud Browser. We never save your password; the profile is encrypted with AES-256-GCM, the cipher 1Password uses.
- A+ on Qualys SSL Labs, securityheaders.com and Mozilla Observatory.
- The model never sees a login.
- No stored passwords, no CAPTCHA solving, no MFA bypass.

**You stay in control**

- Scope each API key: its apps, its tools, read only or read and write.
- Anything that reaches other people waits for your OK, so a leaked key cannot post or message as you.
- Every background request listed in your Background activity. Disable for agents in one click.

**Kept working for you**

- We test every integration every 6 hours.
- When Postscript changes, the tool pauses until we fix it.
- Failed calls cost nothing.

## Is it safe to connect Postscript to Cotlet?

Yes. You sign in to Postscript yourself, in your own Cloud Browser, and we never save your password. Your agents only get Postscript once you enable it, and every background request is listed. The browser profile is stored encrypted with AES-256-GCM, the same cipher 1Password uses for its vaults and Apple for iCloud Keychain. Independent public scanners grade cotlet.dev A+ and find it clean; click a result to rerun it yourself.

- **A+ on Qualys SSL Labs**: Encryption in transit: TLS setup and certificates, on all four server addresses. [Live result](https://www.ssllabs.com/ssltest/analyze.html?d=cotlet.dev)
- **A+ on securityheaders.com**: Browser protections sent with every page, all six headers present. [Live result](https://securityheaders.com/?q=cotlet.dev&followRedirects=on)
- **A+ on Mozilla Observatory**: Mozilla's web security baseline: score 120 of 100, 12 of 12 tests passed. [Live result](https://developer.mozilla.org/en-US/observatory/analyze?host=cotlet.dev)
- **Clean on Sucuri SiteCheck**: No malware, spam or defacement, and not on any of 9 blocklists, Google Safe Browsing included. [Live result](https://sitecheck.sucuri.net/results/cotlet.dev)

[How Cotlet protects your access](https://cotlet.dev/security.md)

### Common concerns

**Who runs Cotlet?**

Cotlet is run by Take Group, a Polish software company working since 2019. Take Group runs about 3,200 websites on its own systems and has its own DevOps team for infrastructure security. We built and used integrations like this inside the company for years before opening them as Cotlet.

**Is this an official Postscript integration?**

No, Cotlet is independent of Postscript. Postscript's own API is too limited for this work. Cotlet works through your own Postscript account, the way you use Postscript in the browser, so you need no partner approval and no developer setup.

**What about client data and GDPR?**

Cotlet is run from the EU and follows the GDPR. Cloud Browsers run in Finland, a Tier 1 country in the ITU Global Cybersecurity Index 2024. Data passes through a call and is not kept after it.

**Can I start with read only?**

Yes. Enable the app for agents as read only, or make the API key read only, and anything that reaches other people waits for your OK unless you switch that off per tool.

**Is it reliable?**

Every Cotlet service is checked every 3 minutes from Europe, North America, Asia and Australia. The live results and any outage are public at status.cotlet.dev.

**How do I stop?**

Press Disable for agents next to Postscript in your console: your agents lose access at once and you stay signed in. Signing out of Postscript in the browser works too, and Reset browser deletes the whole profile.

## Is there a Postscript MCP server on GitHub?

Yes. Community Postscript MCP servers exist on GitHub, usually maintained by one person. You install one on your own computer, give it an API key and keep it running yourself, and it reaches only what the Postscript API exposes. Cotlet hosts the same kind of server for you, works in the dashboard, and our team keeps it working.

|  | GitHub MCP server | Cotlet |
|---|---|---|
| Setup | Clone the repo, install it, create an API key, add it to each MCP client | Sign up, sign in to Postscript once, add one MCP server or API key |
| What it reaches | What the Postscript API exposes: subscribers, events, unsubscribe | What the dashboard does: segments, campaign flows, keywords, Conversations, Message Analytics |
| When Postscript changes | It breaks until you or the maintainer fix it | Our team tests it daily and fixes it for you; failed calls are free |
| Your Postscript access | A private API key in a file on your computer, readable by any program you run | Your own Cloud Browser in the EU, profile encrypted, only for the apps you enable, disabled for agents in one click |
| When the session expires | The key works until you revoke it; nothing else to renew | Your Cloud Browser keeps you signed in; if Postscript logs you out, your agent gets a link to sign in again |
| Upkeep | You update, monitor and debug it yourself | Nothing to host or update |
| Where it runs | Your computer, while it is on | Hosted: Claude Code, Codex, Cursor, n8n and scripts, also on a schedule |
| Price | Free, paid for with your time | Free 7-day trial, then pay-as-you-go credit packs, no subscription |

### Which one fits you

**Pick Cotlet if**

- you are not a developer, or you do not want to maintain a server
- you need it to keep working when Postscript changes, without checking it yourself
- your agent or a script should run it on a schedule, also while your computer is off

**Pick an open-source server if**

- you are comfortable installing, updating and fixing it yourself
- you want your sign-in to stay on your own computer
- you only need it now and then, from one MCP client

## How much does the Postscript API cost?

Free 7-day trial with 2,000 credits, no card needed. After that, the Postscript API is pay as you go with no limit on apps: Credit packs from $29 for 5,000 credits, one-time, no subscription. A successful call uses 10 credits (about $0.04 to $0.06), your Cloud Browser uses 50 credits a day while it has an app enabled for agents, however many apps that is, and an agent driving the browser itself uses 5 credits a minute. Credit packs stay valid for 12 months and stack, so unused credits carry over.

| Credits | Price, one time | Calls at 10 credits | Per 1,000 credits |
|---|---|---|---|
| 5,000 | $29 | 500 | $5.80 |
| 15,000 | $79 | 1,500 | $5.27 |
| 32,000 | $149 | 3,200 | $4.66 |
| 60,000 | $249 | 6,000 | $4.15 |

Only successful calls use credits; failed calls and timeouts cost nothing. At a balance of 0 calls pause, never a surprise charge. Authenticate with the `Authorization: Bearer` header. [See full pricing](https://cotlet.dev/pricing.md)

## How Cotlet holds your access

Cotlet hosts MCP servers and REST APIs for apps with no usable API. Your agent works in your own Postscript account.

- **Company details:** Cotlet is run by Take Group sp. z o.o., a company registered in Poland. Its full address and registration numbers are in the Terms of service. [Terms of service](https://cotlet.dev/terms)
- **Your sign-in:** You sign in to Postscript yourself, in your own Cloud Browser: a Chrome we run for you in the EU, one per app. We never save your password (password saving is off), the profile is stored encrypted with AES-256-GCM, and your agents get Postscript only after you enable it. When Postscript signs you out, your agent gives you a link to sign in again. [Security](https://cotlet.dev/security.md)
- **Revoking access:** Press Disable for agents next to Postscript, sign out of Postscript in your Cloud Browser, or reset the browser. Every background request is listed in your Background activity. Actions that reach other people wait for your OK unless you switch that off per tool.
- **What we never do:** Store passwords, solve CAPTCHAs or bypass MFA.
- **Postscript's terms:** You use your own Postscript account and stay responsible for following Postscript's terms. Cotlet is independent and not affiliated with Postscript. [Terms](https://cotlet.dev/terms)
- **Contact:** Questions about the company, security or an app: [contact@cotlet.dev](mailto:contact@cotlet.dev)

## Frequently asked questions

**How do I get access?**

Sign up free, open Postscript in the console and press Request access. Then you create your API key and connect Postscript there.

**Do I need to be technical?**

No. You sign in to Postscript once in your Cloud Browser, a normal Chrome you open from the console, and paste one command into your agent, or one URL into n8n. Your agent can walk you through it. There is no server to install, update or fix.

**Is it safe to connect Postscript to Cotlet?**

Yes. You sign in to Postscript yourself, in your own Cloud Browser in the EU, and we never save your password. Your agents only get Postscript once you enable it, every background request is listed, and the browser profile is stored encrypted with AES-256-GCM, the cipher 1Password uses for its vaults. The AI model never sees a login, posts and messages wait for your OK, and Disable for agents cuts access in one click. Independent scanners grade cotlet.dev A+ on Qualys SSL Labs, securityheaders.com and Mozilla Observatory; live results are on https://cotlet.dev/security.

**Is a hosted server safer than a local one? My Postscript sign-in would leave my computer.**

On Cotlet you sign in inside your own Cloud Browser, which only you open, and its profile is stored encrypted with AES-256-GCM in the EU. Agents get only the apps you enable, and every background request is listed. A local server keeps your Postscript cookie in a plain file on your computer, readable by any program you run, and stops when your computer is off.

**Why does Cotlet send requests instead of clicking in my browser?**

To be fast, Cotlet doesn't click through Postscript's pages. It sends the same requests your browser would, from your browser's IP with its cookies, without opening a window. Postscript sees the same browser and IP you signed in with, and every request is listed in your Background activity.

**What if someone gets my Cotlet API key?**

The key holds no Postscript login or cookies, it only asks Cotlet to run a tool. It can call only the apps and tools you gave it, and a read-only key changes nothing. Anything that reaches other people, like posts, comments or messages, waits for your OK in the dashboard by default, so a leaked key cannot post or message as you. When you switch approval off for a scheduled job, give that job its own key limited to that one tool. Every call is in your activity log, and deleting the key ends access at once.

**Why a signed-in browser and not OAuth, like other integration platforms?**

Postscript offers no OAuth token you can simply grant for these tools: its official API leaves them out or needs a developer app, a plan or an approval first (see the official API section above). That is why Cotlet sets the limits itself: per key, per tool, with your approval before anything reaches other people. Cotlet is run by Take Group sp. z o.o., an EU company (VAT PL6342984273).

**Do I need a Pro or Enterprise plan?**

No. Postscript's official MCP server is available on Pro and Enterprise plans. Cotlet works in your own Postscript account, so it does not depend on that. Postscript's plan rules still apply: more than two keywords need the Growth, Professional or Enterprise plan, and two-way replies work for US and Canadian subscribers.

**Does the agent skip Postscript's SMS rules?**

No. Postscript still holds campaigns until waking hours in each subscriber's time zone, and it excludes unsubscribed people from every segment. Sending marketing texts needs the subscriber's prior express written consent under the TCPA, and you remain the sender. Every send waits for your OK by default.

**Can my agent post or send messages in Postscript without asking me?**

No. Every call to send_preview, schedule_campaign, stop_campaign, create_keyword or reply_to_conversation waits for your OK by default. For scheduled automations you can switch confirmation off per tool in your dashboard, for example only for approvals. create_segment and create_campaign run without asking, because they send nothing to anyone and one call undoes it.

**Can I use the Postscript API in n8n?**

Yes. Add https://cotlet.dev/mcp/v1 with your API key in n8n's MCP Client node, or call its endpoints under https://cotlet.dev/api/v1/postscript from the HTTP Request node.

---

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**Elsewhere:** [Status page](https://status.cotlet.dev) · [Cotlet on GitHub](https://github.com/cotletdev) · [Cotlet on X](https://x.com/cotletdev) · [Cotlet on LinkedIn](https://www.linkedin.com/company/cotletdev) · [Cotlet on Product Hunt](https://www.producthunt.com/products/cotlet) · [Cotlet on Crunchbase](https://www.crunchbase.com/organization/cotlet) · [Cotlet on SaaSHub](https://www.saashub.com/cotlet)

Cotlet.dev is built by Bart Krawczyk and Jake Slugocki, the founders of Take Group sp. z o.o., ul. Wincentego Janasa 4, 40-855 Katowice, Poland. KRS 0000871398, NIP 6342984273, VAT EU: PL6342984273. [About us](https://cotlet.dev/about.md)

Cotlet is an independent service. It is not affiliated with, endorsed by or sponsored by any of the products listed on this site. Product names are trademarks of their respective owners.