Can I use Postmark as a CLI?

Yes. KosmoKrator exposes a Postmark CLI through kosmo integrations:call and the provider shortcut command. Commands can return JSON for scripts, CI, and coding agents.

Can I expose Postmark through MCP?

Yes. The KosmoKrator MCP gateway can expose selected Postmark tools to clients such as Claude Code, Cursor, Codex, and other MCP-compatible tools.

Where are Postmark credentials stored?

Postmark credentials are configured in KosmoKrator's local integration settings and reused by CLI, Lua, and MCP gateway surfaces.

Can I deny write access for Postmark MCP tools?

Yes. Start the gateway with --write=deny for read-only clients, or use ask/allow only for trusted workspaces.

communication

Postmark MCP Integration for Claude Agent SDK

Connect Postmark to Claude Agent SDK through the local KosmoKrator MCP gateway with scoped tools, credentials, and write policy.

9 functions 7 read 2 write API token auth

Submit Postmark feedback View package source

Connect Postmark to Claude Agent SDK

Give Claude Agent SDK workflows access to KosmoKrator integrations through a local MCP server.

Add a KosmoKrator stdio MCP server to the Claude Agent SDK options. The gateway is local, scoped to this integration, and starts with --write=deny so Claude Agent SDK can inspect read-capable tools without receiving write access by default.

Postmark MCP Config for Claude Agent SDK

Use a narrow integration list so the agent does not load unrelated tools.

{
  "mcpServers": {
    "kosmokrator-postmark": {
      "type": "stdio",
      "command": "kosmo",
      "args": [
        "mcp:serve",
        "--integration=postmark",
        "--write=deny"
      ]
    }
  }
}

Run the Gateway Manually

kosmokrator mcp:serve --integration=postmark --write=deny

Why Use KosmoKrator Here

Scoped tools

Expose only Postmark instead of a broad multi-service tool list.

Local credentials

Reuse credentials already configured for the KosmoKrator CLI and Lua runtime.

Write policy

Start read-only, then opt into ask or allow for trusted workspaces.

Postmark Tools Visible to Claude Agent SDK

Claude Agent SDK sees stable MCP tool names generated from the Postmark integration catalog.

MCP tool	Source function	Type	Description
`integration__postmark__postmark_list_messages`	`postmark.postmark_list_messages`	Read	List outbound messages from Postmark. Supports filtering by recipient, sender, subject, status, and tag.
`integration__postmark__postmark_get_message`	`postmark.postmark_get_message`	Read	Get details for a specific Postmark outbound message including body, recipients, and delivery status.
`integration__postmark__postmark_send_email`	`postmark.postmark_send_email`	Write	Send an email through Postmark. Requires To, From, and Subject. Provide either TextBody or HtmlBody.
`integration__postmark__postmark_send_template`	`postmark.postmark_send_template`	Write	Send an email using a Postmark template. Provide either a TemplateId or TemplateAlias along with the template model data.
`integration__postmark__postmark_get_delivery_stats`	`postmark.postmark_get_delivery_stats`	Read	Get email delivery statistics for your Postmark server, including counts of sent, bounced, and spam complaints.
`integration__postmark__postmark_list_templates`	`postmark.postmark_list_templates`	Read	List all email templates in Postmark. Supports pagination.
`integration__postmark__postmark_get_template`	`postmark.postmark_get_template`	Read	Get details for a Postmark email template including subject, HTML body, and text body.
`integration__postmark__postmark_list_servers`	`postmark.postmark_list_servers`	Read	List servers in the Postmark account. Supports filtering by name and pagination.
`integration__postmark__postmark_get_current_user`	`postmark.postmark_get_current_user`	Read	Get the current Postmark server info including name, settings, and delivery stats. Useful as a health check.