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senderkit-mcp-messaging-operations

senderkit-mcp-messaging-operations is a skill for Claude Code, Codex from senderkit/senderkit-skills. It costs 126 tokens per session (1,550 once invoked), scanned A, original, MIT.

Instructions for operating SenderKit through its connected MCP server to send transactional messages. Transactional messages are triggered communications such as email, SMS, push notifications, web push, welcome messages, or one-time passwords.

In plain words
What is it for?
Use it to send messages and perform supported runtime messaging operations such as checking delivery or working with message templates.
Why use it?
They clarify that this add-on operates the live messaging service rather than changing application code. They also require checking the currently available tools before using them.

Skill for Claude CodeCodex

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also agents/openai.yaml present.

Part of the senderkit plugin — 3 skills, 1 MCP server shipped together

not rated 1repo 9d ago A scan 126 tokens original MIT

Good fit Use it to send messages and perform supported runtime messaging operations such as checking delivery or working with message templates.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/senderkit/senderkit-skills/senderkit-mcp-messaging-operations
View source ↗ senderkit/senderkit-skills senderkit.com
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add senderkit/senderkit-skills --skill senderkit-mcp-messaging-operations
Clone the repo
git clone --depth 1 https://github.com/senderkit/senderkit-skills

Made for: Claude Code, Codex.

Or install senderkit, the plugin that ships this one along with the rest of its 3 skills, 1 MCP server.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for senderkit-mcp-messaging-operations

README.md
[![agentmods](https://agentmods.dev/badge/skills/senderkit/senderkit-skills/senderkit-mcp-messaging-operations/github.svg)](https://agentmods.dev/skills/senderkit/senderkit-skills/senderkit-mcp-messaging-operations)
Your own site
<a href="https://agentmods.dev/skills/senderkit/senderkit-skills/senderkit-mcp-messaging-operations"><img src="https://agentmods.dev/badge/skills/senderkit/senderkit-skills/senderkit-mcp-messaging-operations/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for senderkit-mcp-messaging-operations

Your own site · 80×15
<a href="https://agentmods.dev/skills/senderkit/senderkit-skills/senderkit-mcp-messaging-operations"><img src="https://agentmods.dev/badge/skills/senderkit/senderkit-skills/senderkit-mcp-messaging-operations.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 126 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,550 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00126 $0.01550
Opus 5 $0.00063 $0.00775
Sonnet 5 $0.00025 $0.00310
Haiku 4.5 $0.00013 $0.00155

Measured 10d ago against content hash 4dd28b3ab7ec, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

senderkit-mcp-messaging-operations scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/senderkit-mcp-messaging-operations/SKILL.md · 88 lines

How it starts

The opening of the file, as written. The whole thing — 88 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SenderKit MCP messaging operations

Use this skill when SenderKit is connected as an MCP server and the user wants you to operate SenderKit through tool calls. The documented MCP surface is small and tool-only: ten tools, all prefixed with senderkit_.

This skill operates SenderKit at runtime via MCP and does not change application code. To add or wire SenderKit into a codebase (SDK/REST integration, migrating a provider), use the senderkit-integration skill instead.

Source of truth and drift

The connected MCP server's advertised tool list is the runtime source of truth, not this document.

  • The tool map below mirrors the published surface at https://docs.senderkit.com/mcp/tools (ten tools). Treat that page as canonical when the two disagree, and prefer the live tool list over both.
  • If the connected server advertises an additional senderkit_* tool that is not listed here, you may use it after reading its tool schema. Do not assume a tool exists because it appears here; if a listed tool is absent at runtime, skip it and tell the user.
  • Older or restricted servers may expose fewer tools (for example without the template-authoring tools). Confirm a tool is present before relying on it.

Required workflow

  1. Check context before acting.

    • Call senderkit_context before any send or cancellation.
    • Tell the user whether the active connection is test or live.
    • In live mode, do not send or cancel unless the user's request clearly authorizes that real-world action.

  2. Prefer template sends.

    • Use senderkit_send when the user names or implies an existing template.
    • If the template slug is uncertain, call senderkit_templates_list.
    • Before sending with an unfamiliar slug, call senderkit_templates_get to inspect the template's channel, status, and published version.
    • Pass template variables in vars as a JSON object.
    • Use version only when the user asks to pin a specific template version or the workflow requires a known version.

Read the full file on GitHub · 88 lines

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 88 lines · 126 tokens per session scan A 4dd28b3ab7ec

Subscribe to this mod's changes

senderkit-mcp-messaging-operations is a skill published in the GitHub repository senderkit/senderkit-skills (1 stars, last pushed 9d ago), licensed MIT. It adds 126 tokens to every session and 1,550 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Claude Codeagent-skillsai-agentclaude-plugincodexskills
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