PRODUCT LAUNCH · NOVEMBER 2026

Introducing the BulkResponse API: An Email Marketing API for Python and Claude

Automate bulk email, list sync and campaigns with a REST API, a Python client, or a Claude skill

By the BulkResponse Team · 8 minute read · Docs: app.bulkresponse.com/web/api/docs

Your email marketing shouldn’t stop at the edge of the BulkResponse dashboard. Today we’re launching the BulkResponse Web Account API, a JSON REST email marketing API that gives your apps, scripts and integrations full access to your lists, subscribers, campaigns, autoresponders and stats. Sync contacts the moment they sign up, send personalised campaigns with spintax, and run email automations from your own code, all on top of the same bulk email features you already use. We’re also releasing two ready-made clients: a free Python client, and a Claude skill that lets you run your BulkResponse account just by asking Claude.

• 30+
  endpoints
• 100
  contacts per bulk call
• 13
  personalisation tags
• 0
  dependencies in the Python client

1. Why use an email marketing API?

Most of our customers don’t collect contacts in one place. Leads arrive from website forms, checkout pages, CRMs, webinars and spreadsheets. Copying them into BulkResponse by hand is slow and error-prone, and it means your welcome emails go out late or not at all. An API closes that gap: every new contact lands on the right list automatically.

With the API you can:

• Sync subscribers automatically from your website, CRM or store the moment someone signs up.
• Create and send campaigns from your own systems, for example a weekly newsletter generated from your blog.
• Start autoresponder series the moment a new customer joins a list.
• Pull stats into your own dashboards: opens, clicks, bounces and unsubscribes for every send.
• Keep your lists clean by managing suppressions and unsubscribes in code, alongside our email list cleaning service.

Your tools talk to the API. BulkResponse handles the sending.

2. What the bulk email API can do

The API is a simple JSON REST API. Every request is authenticated with your personal API key, and every response has the same shape, {"status": "success", "message": "...", "data": {...}}, so it’s easy to use from any language. Campaigns can go out through BulkResponse delivery, your own SMTP relay, or a connected mailbox or SMTP integration.

3. Personalisation placeholders and spintax

Placeholders: every email feels personal

Campaigns and autoresponders support personalisation tags in the subject line, HTML and plain text. Each subscriber sees their own details:

%%first_name%% %%last_name%% %%email%% %%city%%
%%state%% %%zip%% %%country%% %%address1%%
%%address2%% %%cellphone%% %%cellcountrycode%%
%%homephone%% %%workphone%%

Custom fields defined on your list work too. A field named Company becomes %%Company%%.

Spintax: a different version for every recipient

Sending the exact same text to thousands of people is a weak spot for deliverability. With spintax, BulkResponse picks one option per recipient when the email is sent: Want help writing variations? Our AI Spintax Generator creates them for you.

Subject: {{RANDOM |Quick question|A short note|Following up}}, %%first_name%%

{{RANDOM |Hi|Hello|Hey}} %%first_name%%,

{{RANDOM |We put together|Here is}} an update for %%city%%.

One template, three different inboxes: spintax and placeholders working together.

4. Getting started with the API in three steps

1. Get your API key

   Account Settings → API → Generate API key (or Copy).

2. Note the base URL

   https://app.bulkresponse.com/web/api/v1

3. Make your first call

   Send the key in the X-Auth-Token header. That’s it.

Your API key lives under Account Settings → API.

Your first call fetches your account summary:

curl -s "https://app.bulkresponse.com/web/api/v1/stats/account" \
  -H "X-Auth-Token: YOUR_API_KEY"

Adding a subscriber is just as easy:

curl -s -X POST "https://app.bulkresponse.com/web/api/v1/subscribers" \
  -H "X-Auth-Token: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"list_id": 123, "email": "ayesha@example.com",
       "first_name": "Ayesha", "city": "Lahore"}'

Full reference, with every endpoint, every field and a copy-ready example for each: https://app.bulkresponse.com/web/api/docs

5. Choose your way in: REST API, Python or Claude

Both clients can be downloaded from the API clients section of the API docs portal.

6. The Python client for the BulkResponse API

A single file, bulkresponse_api.py, covering every endpoint. It uses only Python’s standard library, so there’s nothing to pip install (Python 3.8 or newer). It handles authentication, pagination and errors, and if you reach the hourly limit it waits and retries automatically.

Set it up

1. Download bulkresponse-python-client.zip from the API docs portal and unzip it.
2. Store your key and base URL as environment variables. On macOS or Linux:

export BULKRESPONSE_API_KEY="paste-your-key-here"
export BULKRESPONSE_API_URL="https://app.bulkresponse.com/web/api/v1"

On Windows PowerShell, use setx BULKRESPONSE_API_KEY "..." and setx BULKRESPONSE_API_URL "...", then open a new window. To check it works, run python3 bulkresponse_api.py account.

Use it

from bulkresponse_api import BulkResponseClient, spintax

br = BulkResponseClient()  # reads your key and URL

# Import contacts, 100 per request
br.add_subscribers_bulk(123, [
    {"email": "bilal@example.com", "first_name": "Bilal"},
    {"email": "sara@example.com", "first_name": "Sara"},
])

# Personalised campaign with spintax, sent and tracked
camp = br.create_campaign(
    name="Winter sale",
    subject=spintax("Quick question", "A short note") + ", %%first_name%%",
    html="<p>{{RANDOM |Hi|Hello}} %%first_name%%, our winter sale is live.</p>")
job = br.send_campaign(camp["campaignid"], [123], from_name="Acme Team")
print(br.wait_for_send(job["jobid"]))

# A three-step welcome series: now, after 1 day, after 3 days
br.create_autoresponder_series(123, [
    {"subject": "Welcome, %%first_name%%", "html": welcome,
     "hours_after_subscription": 0},
    {"subject": "A quick tip", "html": tip,
     "hours_after_subscription": 24},
    {"subject": "Still with us?", "html": last,
     "hours_after_subscription": 72},
], name_prefix="Welcome")

It also includes a command-line tool for everyday jobs, such as importing a CSV in one line:

python3 bulkresponse_api.py import-csv 123 contacts.csv

Import a CSV and check results from the command line.

7. The Claude skill: run BulkResponse email marketing by asking Claude

This is the part we’re most excited about. The BulkResponse Claude skill teaches Claude, Anthropic’s AI assistant, how to use your BulkResponse account through the API. Instead of writing code, you describe what you want in plain language, and Claude does the work and reports back.

The skill includes the Python client, a full API reference, and the rules for using the API correctly: how placeholders and spintax work, how to stay within your rate limit, how autoresponder timing works, and more.

Ask in plain language, and get answers and actions from your real account.

Option A: Claude Code (recommended)

1. Download bulkresponse-api-claude-skill.zip from the API docs portal.
2. Unzip it into your skills folder:

   mkdir -p ~/.claude/skills && unzip bulkresponse-api-claude-skill.zip -d ~/.claude/skills/

3. Add your key and base URL to ~/.claude/settings.json:

   {
     "env": {
       "BULKRESPONSE_API_KEY": "paste-your-key-here",
       "BULKRESPONSE_API_URL": "https://app.bulkresponse.com/web/api/v1"
     }
   }

4. Restart Claude Code and ask: “Show my BulkResponse account stats.” Your key stays in your own settings file. It’s never typed into a chat.

Option B: Claude.ai or the Claude desktop app

1. Go to Settings → Capabilities and make sure code execution is turned on.
2. Under Skills, click Upload skill and choose the zip file, without unzipping it.
3. Start a chat and ask Claude to do something in BulkResponse. Claude will ask for your API key and base URL. A key pasted into a chat is stored with that chat, so many customers create a key for this purpose and regenerate it afterwards.

What you can ask Claude

👥 Lists & contacts

• “List my lists with their real subscriber counts.”
• “Import contacts.csv into list 123 and tell me which rows were skipped and why.”
• “Move everyone on Trial who isn’t from acme.com to Prospects.”
• “Add these domains to my global suppression list.”

✉️ Campaigns

• “Write a welcome email personalised with first name and city, with three spintax greetings.”
• “Send campaign 226 to Customers through my SMTP channel.”
• “Schedule the newsletter for tomorrow at 9 am.”
• “Pause that send.” / “Resume it.”

🔁 Autoresponders

• “Create a three-step welcome series on Customers: now, after one day, after three days.”
• “Pause my onboarding series.”

📊 Reporting

• “How did my last five campaigns perform?”
• “How are my autoresponders doing?”
• “How many API calls do I have left this hour?”

8. Good to know: API limits and rules

9. FAQ

Is the API included in my plan?
Yes. The API is available on every BulkResponse web account. Generate your key under Account Settings → API. See BulkResponse pricing for plan details and hourly API allowances.

Which programming languages can I use?
Any language that can make HTTPS requests and read JSON. We provide a ready-made Python client, and every endpoint on the docs portal has a copy-ready curl example.

Do I need to know how to code to use the Claude skill?
No. Install the skill, add your key, and ask Claude in plain language. Claude writes and runs the code for you.

Can Claude send email without my permission?
No. Claude asks for your confirmation before anything that sends email or deletes data, and shows you exactly who will receive it.

What happens if my key leaks?
Click Regenerate API key in Account Settings → API. The old key stops working immediately.

Can I use my own SMTP server?
Yes. Campaign sends can go through BulkResponse delivery, one of your SMTP channels, or a connected mailbox.

Does the API help with deliverability?
The API uses the same sending, suppression and bounce handling as the dashboard, so the same rules apply. For best results, follow our cold email deliverability guide.

10. Start building today

We’d love to see what you build. If you have questions, ideas for new endpoints or feedback on the clients, contact our support team. Your feedback shapes the next version of the API.

Happy sending!
The BulkResponse Team