# Mail Blaze Muse connector

From musedirectory.ai, the independent directory of Meta Muse connectors. Not affiliated with Meta.

## Mail Blaze

Manage mailing lists, subscribers, email campaigns and transactional emails through Mail Blaze.

- Record: https://musedirectory.ai/connector/mail-blaze
- Category: Marketing & Ads
- Developer: usefulapi (https://usefulapi.io/mailblaze/)
- Muse status: Extra setup. Not in Muse's Connectors list yet. Muse can still use it: its page gives you a request to paste into Muse.
- Health: Working, 189ms, checked 2026-10-29T23:41:18Z
- Endpoint: https://mailblaze.usefulapi.io/mcp
- Auth: No account needed; Pricing: unknown
- Screening: Screened, no issues found (2026-10-29T23:41:18Z)
- Source: Found in the official MCP Registry (io.usefulapi/mailblaze) https://registry.modelcontextprotocol.io/v0/servers?search=io.usefulapi%2Fmailblaze

Connect to Mail Blaze to manage subscriber lists, create and send email campaigns to segments, build email templates, track opens and clicks, and send transactional emails. Requires Mail Blaze account and API key.

Example request: "Send a welcome email campaign to new subscribers on my mailing list next Monday at 9am."

How to connect: Not in Muse's Connectors list yet, but Muse can still use it. Paste this into Muse: "Use Mail Blaze to help me. It is a free service with an MCP server at https://mailblaze.usefulapi.io/mcp. It does not need an API key. Ask me before you share anything with it." Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.

Tools:
- mailblaze_list_lists: List the account's mailing lists (name, uid, subscriber counts, defaults). Use the list uid in the other tools. Paged: page + per_page.
- mailblaze_get_list: Get one mailing list by its uid: general settings, default sender, company details and counts.
- mailblaze_list_list_fields: List the fields of a mailing list (label, tag, type, required). The tags (EMAIL, FNAME, LNAME, custom ones) are the keys used when adding or updating subscribers.
- mailblaze_list_segments: List the segments defined on a mailing list (uid, name). A segment uid can be used when creating a campaign.
- mailblaze_list_subscribers: List the subscribers of a mailing list (sets of 10 per page; use page to go on). Contains personal data (emails, names).
- mailblaze_get_subscriber: Get one subscriber of a list by subscriber uid (status, fields, dates).
- mailblaze_find_subscriber_by_email: Look up a subscriber in one list by email address. Returns the subscriber (with its uid) or a not-found error.
- mailblaze_add_subscriber: WRITE, MAY SEND A CONFIRMATION EMAIL: add one subscriber to a mailing list. Depending on the list's settings Mail Blaze may send the person a confirmation (double opt-in) email. Only add people who agreed to receive your email. An email that is already on the list answers with a 
- mailblaze_add_subscribers_bulk: WRITE, MAY SEND CONFIRMATION EMAILS: add up to 100 subscribers to a mailing list in one request; an email already on the list is updated instead. Depending on the list's settings Mail Blaze may send confirmation emails. Only add people who agreed to receive your email.
- mailblaze_update_subscriber: WRITE: update a subscriber's name or custom fields. Pass the subscriber's current email (Mail Blaze requires it) plus only the values to change. Does not change subscription status.
- mailblaze_unsubscribe_subscriber: WRITE: set a subscriber's status to unsubscribed so they receive no more campaigns from this list. By default Mail Blaze also adds the address to the account's local blacklist. Do this only when the person asked to stop (or a data-protection request requires it). The subscriber r
- mailblaze_resubscribe_subscriber: WRITE: set a previously unsubscribed subscriber back to subscribed so campaigns reach them again. Only do this when the person asked to be re-added (consent).
- mailblaze_list_templates: List the account's email templates (uid, name). A template uid is needed to create a campaign.
- mailblaze_get_template: Get one email template by uid (name and content).
- mailblaze_create_template: WRITE: create an email template from HTML (the tool base64-encodes it). Mail Blaze requires the HTML to contain an unsubscribe link. Sends nothing.
- mailblaze_list_campaigns: List the account's email campaigns (uid, name, status, dates). Use the campaign uid for details and reports.
- mailblaze_get_campaign: Get one campaign by uid: sender, subject, list, template, status and schedule.
- mailblaze_create_campaign: WRITE, SENDS EMAIL TO PEOPLE: create a campaign for a mailing list (or one of its segments) from an existing template and schedule it for send_at. Once it goes out it reaches every subscriber of the list or segment, may use sending credit and cannot be recalled. Confirm the list,
- mailblaze_get_campaign_summaries: Bulk report summary (sent, opens, clicks, bounces, unsubscribes) for up to 50 campaigns in one call. Read-only (it is a POST in the API only because of the id list).
- mailblaze_get_campaign_inbox_breakdown: Inbox-provider breakdown (e.g. Gmail, Outlook, Yahoo) of a campaign's delivery.
- mailblaze_list_campaign_events: List the individual events of a campaign by kind: opens, clicks, bounces or unsubscribes. Cursor-paged: pass the reply's next_cursor back until it is null. For very large campaigns Mail Blaze answers 202 with a job_id; check it with mailblaze_get_report_job.
- mailblaze_get_subscriber_activity: Email activity (sends, opens, clicks, bounces) of one subscriber by email address, optionally limited to one list. Cursor-paged.
- mailblaze_get_report_job: Status (and result when finished) of an asynchronous report job, as returned in a 202 reply with a job_id.
- mailblaze_list_transactional_emails: List the transactional emails sent through the account (uid, recipient, subject, status). Paged.
- mailblaze_get_transactional_email: Get one transactional email by uid: recipient, subject, status and timestamps.
- mailblaze_send_transactional_email: WRITE, SENDS ONE EMAIL NOW: send a single one-to-one email to one recipient through Mail Blaze. It leaves immediately, uses sending credit and cannot be recalled. Give either html (the body) or template_id (a transactional template, with merge_tags covering every tag in it), not 

Screening checks:
- MCP handshake: pass (Answered in 189ms)
- Domain against threat feeds (Cloudflare security DNS): pass (mailblaze.usefulapi.io, usefulapi.io not flagged)
- Published packages against the OSV malicious-package database: n/a (No npm or PyPI package published)
- Hidden instructions or invisible characters in tool text: pass (26 tools read, nothing found)
- Inputs asking for passwords, card numbers or seed phrases: pass (None found)
- Domain and redirects: pass (No redirects off the domain)
- AI review of purpose and tool behavior: pass (No concerns)