Add SenderKit from your coding agent

SenderKit Skills is an open-source plugin that teaches an AI coding agent how to work with SenderKit. Install it once and your agent can add transactional email, SMS, push, and web-push to your codebase — and send, inspect, and manage messages at runtime — without you spelling out the API every time. It’s portable: the same plugin runs in Claude Code, OpenAI Codex, Cursor, and other Agent Skills-compatible assistants.

This is different from the two other AI integrations in these docs. The MCP server is the connection an agent calls SenderKit through; the AI-agent guide gives your own app’s agent a send tool. The skills plugin is the layer that makes a coding agent good at both — it ships the know-how, and bundles the MCP server so runtime sends work out of the box.

The two skills

The plugin contains one senderkit plugin with two skills. They split along a single line: does the agent change your code, or operate SenderKit at runtime?

senderkit-integration

Writes SenderKit into your app. Detects your stack, adds SenderKit behind a small local wrapper, migrates an existing provider (Resend, SendGrid, Postmark, Mailgun, SES, SMTP, Twilio, FCM, APNs, Expo) or routes through it, and verifies in test mode before live traffic.

senderkit-mcp-messaging-operations

Operates SenderKit at runtime over MCP. Sends templated or raw messages, lists and inspects messages, drafts templates, and cancels pending sends — without touching code.

You don’t have to name the skills — they activate on everyday messaging requests.

You ask	Skill that helps
”Add a welcome email when a user signs up”	`senderkit-integration`
”Set up SMS OTP / verification codes”	`senderkit-integration`
”Add push notifications to this project”	`senderkit-integration`
”Switch my email provider to SenderKit (or route through it)“	`senderkit-integration`
”Send a test email and check its delivery status”	`senderkit-mcp-messaging-operations`
”Why did this message fail? Cancel that scheduled send”	`senderkit-mcp-messaging-operations`

Install

Claude Code
Codex
Cursor

Install from the marketplace:

/plugin marketplace add senderkit/senderkit-skills
/plugin install senderkit@senderkit-skills

This loads both skills and the SenderKit MCP server from the repo’s .mcp.json (OAuth — no key stored). Run /mcp, sign in, and pick a workspace and test/live mode.Developing against a local checkout instead:

claude --plugin-dir .

Check it works: run /mcp — the senderkit server should be connected — or ask “Use senderkit-integration to add a welcome email.”

Codex discovers skills from .agents/skills/ directories. Vendor the skills into your user scope (every repo) or a single repo’s scope:

git clone https://github.com/senderkit/senderkit-skills.git
mkdir -p ~/.agents/skills
cp -R senderkit-skills/skills/senderkit-integration ~/.agents/skills/
cp -R senderkit-skills/skills/senderkit-mcp-messaging-operations ~/.agents/skills/
# repo-scoped instead? copy into <your-repo>/.agents/skills/

Restart Codex so it picks them up. Then connect MCP with an API key — set SENDERKIT_API_KEY (the sk_live_ / sk_test_ prefix selects mode), or run senderkit mcp install --client codex.Check it works: run /skills (the SenderKit skills should be listed) or invoke one explicitly with $senderkit-integration.

Load the repo as a local plugin:

git clone https://github.com/senderkit/senderkit-skills.git
ln -s "$(pwd)/senderkit-skills" ~/.cursor/plugins/local/senderkit

Reload Cursor (Developer: Reload Window). Skills appear under Settings → Rules & Skills. Then connect MCP with an API key — set SENDERKIT_API_KEY (the sk_live_ / sk_test_ prefix selects mode), or run senderkit mcp install --client cursor, and toggle the server under Settings → MCP.Check it works: type /senderkit-integration in chat, or ask “Send a test email and check its status via SenderKit MCP.”

Installing the plugin gives you the senderkit_* MCP tools, but auth differs by client: Claude Code uses OAuth (no key stored); Codex and Cursor use an API key via SENDERKIT_API_KEY. For every other client, manual config, and self-hosting, see MCP installation. Start with an sk_test_ key so a coding agent can’t send to real people until you trust it.

What’s next

MCP Server

The connection the messaging-operations skill rides on — tools and modes.

MCP installation

Connect the MCP server in any client, including manual config.

Send from your AI agent

The other direction — give your app’s own agent a send tool.

MCP tools

Every tool the messaging-operations skill can call.

​The two skills

senderkit-integration

senderkit-mcp-messaging-operations

​Install

​What’s next

MCP Server

MCP installation

Send from your AI agent

MCP tools

The two skills

Install

What’s next