cold-email

cold-email is a skill for Claude Code from Bluecraft-AI/machfive-skills. It costs 24 tokens per session (2,589 once invoked), scanned A, original, MIT.

An AI-assisted tool that creates personalized cold-email sequences from lead information. Cold email is unsolicited email sent to potential customers or contacts.

In plain words
What is it for?
Use it to generate outreach sequences from lead data through the MachFive API, after configuring an API key and choosing a campaign.
Why use it?
It reduces the work of researching prospects and writing separate, relevant messages instead of reusing generic templates.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the cold-email plugin — 1 skill shipped together

Good fit Use it to generate outreach sequences from lead data through the MachFive API, after configuring an API key and choosing a campaign.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/bluecraft-ai/machfive-skills/cold-email
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 Bluecraft-AI/machfive-skills --skill cold-email
Clone the repo
git clone --depth 1 https://github.com/Bluecraft-AI/machfive-skills

Made for: Claude Code.

Or install cold-email, the plugin that ships this one along with the rest of its 1 skill.

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 cold-email

README.md
[![agentmods](https://agentmods.dev/badge/skills/bluecraft-ai/machfive-skills/cold-email/github.svg)](https://agentmods.dev/skills/bluecraft-ai/machfive-skills/cold-email)
Your own site
<a href="https://agentmods.dev/skills/bluecraft-ai/machfive-skills/cold-email"><img src="https://agentmods.dev/badge/skills/bluecraft-ai/machfive-skills/cold-email/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 cold-email

Your own site · 80×15
<a href="https://agentmods.dev/skills/bluecraft-ai/machfive-skills/cold-email"><img src="https://agentmods.dev/badge/skills/bluecraft-ai/machfive-skills/cold-email.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 24 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,589 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 $0.00024 $0.02589
Opus 5 $0.00012 $0.01295
Sonnet 5 $0.00005 $0.00518
Haiku 4.5 $0.00002 $0.00259

Measured 10d ago against content hash bcd71270f5e8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

cold-email 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.

cold-email/skills/cold-email/SKILL.md · 220 lines

How it starts

The opening of the file, as written. The whole thing — 220 lines — stays where its author put it; the contents beside it link to each section on GitHub.

MachFive - AI Cold Email Generator

Generate personalized cold email sequences from lead data. MachFive uses AI to research prospects and craft unique, relevant outreach - not templates.

Setup

  1. Get your API key at https://app.machfive.io/settings (Integrations → API Keys)
  2. Set MACHFIVE_API_KEY in your environment

Campaign ID

Every generate request needs a campaign ID in the URL: /api/v1/campaigns/{campaign_id}/generate (or /generate-batch).

  • If the user has not provided a campaign name or ID: Call GET /api/v1/campaigns (see below) to list campaigns in their workspace, then ask them to pick one by name or ID before running generate.
  • Where to get it manually: https://app.machfive.io/campaigns → open a campaign → copy the ID from the URL or settings.
  • No default: The skill does not assume a campaign. The user (or agent config) must provide one. Agents can store a default campaign ID for the workspace if the user provides it (e.g. "use campaign X for my requests").

Endpoints

List Campaigns (discover before generate)

List campaigns in the workspace so the agent can ask the user which campaign to use when they haven't provided a name or ID.

GET https://app.machfive.io/api/v1/campaigns
Authorization: Bearer {MACHFIVE_API_KEY}

Or use X-API-Key: {MACHFIVE_API_KEY} header.

Optional query: ?q=search or ?name=search to filter by campaign name.

Response (200):

{
  "campaigns": [
    { "id": "cb1bbb14-e576-4d8f-a8f3-6fa929076fd8", "name": "SaaS Q1 Outreach", "created_at": "2025-01-15T12:00:00Z" },
    { "id": "a1b2c3d4-...", "name": "Enterprise Leads", "created_at": "2025-01-10T08:00:00Z" }
  ]
}

If no campaign name or ID was given, call this first, then ask the user: "Which campaign should I use? [list names/IDs]."

Single Lead (Sync)

Generate an email sequence for one lead (3–5 emails per lead). Waits for completion, returns the sequence directly. The request can take 3–5 minutes (AI research + generation); use a client timeout of at least 300 seconds (5 min) or 600 seconds (10 min). Do not use a 120s timeout or the response will be cut off.

POST https://app.machfive.io/api/v1/campaigns/{campaign_id}/generate
Authorization: Bearer {MACHFIVE_API_KEY}
Content-Type: application/json

Read the full file on GitHub · 220 lines

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 · 220 lines · 24 tokens per session scan A bcd71270f5e8

Subscribe to this mod's changes

cold-email is a skill published in the GitHub repository Bluecraft-AI/machfive-skills (2 stars, last pushed 6mo ago), licensed MIT. It adds 24 tokens to every session and 2,589 once invoked, about $0.0001 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.