Use Sendmux attachment workflows without wasting model context on base64. Use when uploading, downloading, reading, forwarding, or sending email attachments through Sendmux MCP, CLI, SDKs, or direct HTTP, especially when choosing filepath vs presigned upload URL vs inline base64, reading inbound attachments with mailboxreadattachment, fetching short-lived downloadurl links, or attaching local files to outbound mail.
EnglishUse the Sendmux command-line interface for terminal-driven Sendmux work. Use when the user wants install commands, profiles, key-scope preflight, --json output, colon-namespaced Sendmux commands, request body/path/query/header flags, or CLI examples for Management, Mailbox, or Sending API operations.
EnglishDesign and route Sendmux email workflows for AI agents, including skill installation, self-registration, secure agent credential-bundle storage, owner approval, and runtime email operations. Use when a user wants to give an AI agent its own inbox or email address, let an agent receive/search/triage/reply to mail, draft human-approved replies, send notifications, monitor mailbox state, or build email-based agent workflows even when the user does not mention Sendmux by name.
EnglishSendmux setup, skill installation, API key validation, agent access, secure agent credential-bundle storage, and first-call guidance. Use when the user wants to install Sendmux tooling or skills, check whether an smxroot, smxmbx, or smxagent credential works, choose MCP vs CLI vs SDK, connect an agent to Sendmux email, configure auth, self-register an agent, or make the first harmless Sendmux API call from an agent, terminal, or application.
EnglishWork efficiently with one Sendmux mailbox from an AI agent. Use for reading, searching, counting, syncing, triaging, filing, deleting, threading, or replying from a mailbox with an smxmbx key or scoped smxagent token, especially when the user asks an agent to inspect an inbox, find relevant messages, mark messages, or continue from a prior mailbox sync state.
EnglishManage Sendmux account-level resources with an smxroot key. Use for domains, mailbox provisioning, mailbox API keys, sending accounts, webhooks, billing, spend, delivery logs, incoming logs, metrics, and other team administration tasks; route mailbox reading, triage, sync, and replies to sendmux-mailbox-agent.
EnglishConfigure Sendmux Model Context Protocol servers for AI agent clients, using hosted OAuth first when supported and secret-backed local env config otherwise. Use when the user wants to install sendmux-mcp, connect the hosted Sendmux MCP endpoint, run local stdio or HTTP MCP servers, set mailbox/management/sending key scopes, add bearer headers, or write MCP config for Claude Code, Cursor, Codex, VS Code/Copilot, Copilot CLI, Gemini CLI, Cline, or Windsurf/Cascade.
EnglishSend email with Sendmux, including owner-approved Sending-resource smxagent tokens from claim-token exchange. Use when the user wants to send one email, send multiple emails, choose single vs batch sending, add idempotency keys, include attachments, compare HTTP Sending API vs SMTP, or use Sendmux MCP, CLI, SDK, or direct HTTP for outbound email.
EnglishChoose the cheapest correct Sendmux surface and call. Use whenever a Sendmux task could be done through MCP, the sendmux CLI, an SDK, or direct HTTP and the user needs low-token, low-round-trip usage: batch sends, mailbox search/count/batch reads, sync deltas, cursor pagination, ETags, conditional requests, idempotency keys, attachment file transfer, or avoiding broad mailbox/log fetches.
EnglishIncludes Sendmux Attachments, Sendmux CLI, Sendmux Email for Agents, and other workflows.
Supported by the Atlas install prompt. Skill-specific requirements vary.
Pack stats
What’s included
Sendmux Attachments
Use Sendmux attachment workflows without wasting model context on base64. Use when uploading, downloading, reading, forwarding, or sending email attachments through Sendmux MCP, CLI, SDKs, or direct HTTP, especially when choosing filepath vs presigned upload URL vs inline base64, reading inbound attachments with mailboxreadattachment, fetching short-lived downloadurl links, or attaching local files to outbound mail.
Sendmux CLI
Use the Sendmux command-line interface for terminal-driven Sendmux work. Use when the user wants install commands, profiles, key-scope preflight, --json output, colon-namespaced Sendmux commands, request body/path/query/header flags, or CLI examples for Management, Mailbox, or Sending API operations.
Sendmux Email for Agents
Design and route Sendmux email workflows for AI agents, including skill installation, self-registration, secure agent credential-bundle storage, owner approval, and runtime email operations. Use when a user wants to give an AI agent its own inbox or email address, let an agent receive/search/triage/reply to mail, draft human-approved replies, send notifications, monitor mailbox state, or build email-based agent workflows even when the user does not mention Sendmux by name.
Sendmux Getting Started
Sendmux setup, skill installation, API key validation, agent access, secure agent credential-bundle storage, and first-call guidance. Use when the user wants to install Sendmux tooling or skills, check whether an smxroot, smxmbx, or smxagent credential works, choose MCP vs CLI vs SDK, connect an agent to Sendmux email, configure auth, self-register an agent, or make the first harmless Sendmux API call from an agent, terminal, or application.
Sendmux Mailbox Agent
Work efficiently with one Sendmux mailbox from an AI agent. Use for reading, searching, counting, syncing, triaging, filing, deleting, threading, or replying from a mailbox with an smxmbx key or scoped smxagent token, especially when the user asks an agent to inspect an inbox, find relevant messages, mark messages, or continue from a prior mailbox sync state.
Sendmux Management
Manage Sendmux account-level resources with an smxroot key. Use for domains, mailbox provisioning, mailbox API keys, sending accounts, webhooks, billing, spend, delivery logs, incoming logs, metrics, and other team administration tasks; route mailbox reading, triage, sync, and replies to sendmux-mailbox-agent.
Sendmux MCP Setup
Configure Sendmux Model Context Protocol servers for AI agent clients, using hosted OAuth first when supported and secret-backed local env config otherwise. Use when the user wants to install sendmux-mcp, connect the hosted Sendmux MCP endpoint, run local stdio or HTTP MCP servers, set mailbox/management/sending key scopes, add bearer headers, or write MCP config for Claude Code, Cursor, Codex, VS Code/Copilot, Copilot CLI, Gemini CLI, Cline, or Windsurf/Cascade.
Sendmux Send Email
Send email with Sendmux, including owner-approved Sending-resource smxagent tokens from claim-token exchange. Use when the user wants to send one email, send multiple emails, choose single vs batch sending, add idempotency keys, include attachments, compare HTTP Sending API vs SMTP, or use Sendmux MCP, CLI, SDK, or direct HTTP for outbound email.
Sendmux Token Efficient Usage
Choose the cheapest correct Sendmux surface and call. Use whenever a Sendmux task could be done through MCP, the sendmux CLI, an SDK, or direct HTTP and the user needs low-token, low-round-trip usage: batch sends, mailbox search/count/batch reads, sync deltas, cursor pagination, ETags, conditional requests, idempotency keys, attachment file transfer, or avoiding broad mailbox/log fetches.
Quick start
- Choose your skills. Select individual skills above, or choose the entire pack.
- Copy the install prompt. Use Copy install prompt above the list.
- Send it to your agent. Paste into your coding agent’s chat. Your agent reviews the source and guides the setup.
Try it with your agent
After installation, start with a request like:
Use the Sendmux Attachments skill to help with my task.
Ask me for the context you need before getting started.Requirements & license
- A coding agent that can access your project files and install skills.
- Your agent checks each skill’s instructions, dependencies, and permissions during setup.
- License details are not provided in these listings. Check the author’s terms before using the skills.