Automate Postmark Email Operations

Automates Postmark transactional email operations - templated batch sending, template management, delivery statistics, bounce/complaint monitoring, and server configuration - through Composio's Postmark toolkit accessed via Rube MCP.

Use this skill when sending templated batch emails, creating or editing email templates, monitoring delivery health and open/click rates, reviewing bounces and spam complaints, or configuring Postmark server settings. Not a fit for email providers other than Postmark, or for tasks unrelated to transactional email operations.

Setup requires Rube MCP connected, an active Postmark connection verified via RUBE_MANAGE_CONNECTIONS with toolkit postmark, and calling RUBE_SEARCH_TOOLS first for current schemas.

Sending templated batch emails uses POSTMARK_LIST_TEMPLATES to find template IDs, optionally POSTMARK_VALIDATE_TEMPLATE to test rendering with sample data, then POSTMARK_SEND_BATCH_WITH_TEMPLATES with a Messages array (each with From/To/TemplateModel) - limited to 500 messages per call, requiring either TemplateId or TemplateAlias (not both), case-sensitive TemplateModel keys matching template variables exactly, and a verified Sender Signature or domain.

Managing templates covers listing, retrieving full HTML/text body details, editing (which replaces entire content, so all fields to keep must be included), and validating rendering before sending - noting Layout-type templates wrap Standard templates so changing a layout affects all linked templates. Monitoring delivery statistics uses POSTMARK_GET_DELIVERY_STATS (bounce counts by type), POSTMARK_GET_OUTBOUND_OVERVIEW (sent/opened/clicked/bounced summary), and POSTMARK_GET_TRACKED_EMAIL_COUNTS, filterable by date range (YYYY-MM-DD), tag, or message stream.

Managing bounces and complaints uses POSTMARK_GET_BOUNCES and POSTMARK_GET_SPAM_COMPLAINTS, filterable by bounce type (HardBounce, SoftBounce, SpamNotification, SpamComplaint, Transient), date range, and recipient email - noting hard bounces indicate permanent failures requiring address removal, and spam complaints affect sender reputation. Configuring server settings uses POSTMARK_GET_SERVER/POSTMARK_EDIT_SERVER for server name, SMTP API activation, bounce/inbound webhook URLs, and open/link tracking modes - noting webhook URLs must be public HTTPS endpoints and tracking changes apply only to future messages.

Common patterns include resolving template variables (fetch the template, inspect {{variable}} placeholders in the body, build a matching TemplateModel dict, validate rendering) and offset-based pagination (count/offset, incrementing until returned results are fewer than the requested count). Known pitfalls cover Postmark's server-level (not account-level) API tokens, the 500-message batch send limit, rate limiting requiring backoff on 429 responses, and defensively parsing responses that may nest data under data or data.data.

Accessed via Rube MCP wrapping Composio's Postmark toolkit, covering Postmark's Templates, Batch Sending, Stats, Bounces/Complaints, and Server configuration APIs.

Teams automating transactional email through Postmark via an MCP-connected agent who need the exact tool sequence, batch limits, and parameter quirks rather than trial-and-error API calls.

POSTMARK_SEND_BATCH_WITH_TEMPLATES: Messages=[{From, To, TemplateModel}], TemplateId=123