WarmInboxes Free MCP: Fleet Planner
Read-only sizing and pricing, a subset of the Free MCP
Tell it a send volume, a list or a number of inboxes and it works out what to buy: the inboxes, the domains or Azure tenants, the daily capacity and the monthly cost at our published prices. If you are replacing inboxes because results fell, it asks you to check the cause first, because a DNS, list or copy problem moves to new inboxes with you.
For anyone planning a cold email fleet, adding capacity, or deciding between Google, Microsoft 365 and Azure.
- Claude: Add to Claude
https://warminboxes.com/mcp/planner(Add by URL; not submitted to the directory) - ChatGPT: Add to ChatGPT
https://warminboxes.com/mcp/planner(Add by URL; not submitted to the directory). ChatGPT: turn on developer mode (Settings, Apps & Connectors, Advanced settings), then Add, Custom MCP server, paste the URL, Authentication: none. - Grok: Add to Grok
https://warminboxes.com/mcp/planner(Works as a custom connector). Grok: Connectors, New Connector, Custom, paste the URL, no authentication. Custom connectors are on Grok’s paid plans. - Claude Code: Copy the command
claude mcp add --transport http warminboxes-free-planner https://warminboxes.com/mcp/planner(Works today) - Cursor, VS Code and other MCP clients: Copy the server URL
https://warminboxes.com/mcp/planner(Streamable HTTP, no authentication)
What to ask it
These 34 prompts are our test suite: each names the tool that answers it, and we rerun every one after each change to the agent.
Sizing
- “I want to send 1,000 cold emails a day. What do I need?”
plan_infrastructure - “Size 5,000 a day on Microsoft 365”
plan_infrastructure - “What would 500 a day cost on fresh inboxes?”
plan_infrastructure - “Plan 2,000 a day on Azure”
plan_infrastructure - “Size 1,000 a day with half the fleet resting”
plan_infrastructure - “If my deal is worth $5,000, what does 1,000 a day return?”
plan_infrastructure - “Cheapest way to run 1,000 a day if I commit for a quarter”
plan_infrastructure - “We need 10,000 emails a day. How many domains?”
plan_infrastructure - “I need to send 1,000 emails a day. Where do I start?”
get_diagnostic_playbook
Quotes
- “Preview 100 inboxes”
quote_inboxes - “Price 100 Azure inboxes”
quote_inboxes - “Quote 150 Azure inboxes”
quote_inboxes - “100 Google inboxes on quarterly billing”
quote_inboxes - “30 fresh Microsoft inboxes, what does that cost?”
quote_inboxes - “Replace 50 burned inboxes”
quote_inboxes
Lists
- “Size this CSV: stripe.com, microsoft.com, gmail.com at 500 a day”
plan_from_list - “Google or Azure for my list? stripe.com, microsoft.com”
segment_esp - “What does stripe.com use for email?”
lookup_mx - “Convert this lead CSV for Instantly”
convert_csv
Planning
- “Plan a rotation for 60 inboxes sending 600 a day”
plan_rotation - “Cheapest way to verify a 50,000-row list”
plan_verification_waterfall
Setup
- “What DNS records do my new sending domains need?”
generate_dns_records - “Can I use stripe.com on Google Workspace?”
check_google_domain - “How old is stripe.com and when does it expire?”
check_domain_expiry
Pricing
- “Show me your price list”
get_pricing
Research
- “Which TLD should I buy for new sending domains?”
find_resources - “How many inboxes should I put on each domain?”
find_resources - “Prewarmed or fresh: which should I buy?”
find_resources - “Is there a calculator for inbox count?”
find_tools
Belongs on the other agent
- “Check my SPF”
check_spf(on the Free MCP) - “Am I blacklisted?”
check_blacklist(on the Free MCP) - “SCL 5 on my Outlook emails”
analyze_microsoft_headers(on the Free MCP)
Before replacing inboxes
- “My reply rate fell, should I buy new inboxes?”
plan_infrastructure - “My replies fell. Should I just buy new inboxes?”
get_diagnostic_playbook
What an answer looks like
“Preview 100 inboxes” quote_inboxes: 100 prewarmed Google inboxes across 34 domains, $800 a month, ready within 48 to 72 hours of payment. This sounds like a diagnostic issue. Check it with WarmInboxes Free MCP before replacing anything: a DNS, list or copy problem moves to new inboxes with you.
“I want to send 1,000 cold emails a day. What do I need?” plan_infrastructure: 67 prewarmed Google inboxes across 23 domains at 15 sends each a day, with the monthly cost and how to order.
“Quote 150 Azure inboxes” quote_inboxes: 2 Azure tenants at $138 a month. Azure is sold by the tenant, up to 100 inboxes each, so the quote says it holds more than asked.
Exactly what it can do
Sizing
- Inboxes and domains for a send volume (estimate)
plan_infrastructure - Fleet estimate from a recipient list
plan_from_list - Price a number of inboxes (quote)
quote_inboxes - Price list
get_pricing
Your list
- ESP segmentation (bulk)
segment_esp - MX records and mail provider
lookup_mx - Sequencer CSV converter
convert_csv
Sending plan
- Inbox rotation schedule (suggested)
plan_rotation - Email verification waterfall
plan_verification_waterfall
Domains and setup
- Google Workspace tenancy
check_google_domain - Domain registration and expiry
check_domain_expiry - SPF and DMARC record generator
generate_dns_records
Research
- How to work a cold email problem (playbook)
get_diagnostic_playbook - Guides, playbooks, studies and videos
find_resources - Read a guide or study
read_resource - Free tool for a job
find_tools
What it will not do
- Every tool is read-only. It does not place an order, send email or change DNS.
- Figures are estimates from published prices and stated sending paces. The exact preview, with real domain and mailbox names, is in the app or on WarmInboxes Infrastructure MCP.
- A first order is a checkout in the WarmInboxes app. Existing customers can order more through WarmInboxes Infrastructure MCP, from clients that send an API key header; ChatGPT and claude.ai cannot connect to it yet.
- It does not diagnose. Checks such as SPF, blocklists and Outlook headers are on the full WarmInboxes Free MCP, and it says so when asked.
- No sizing guarantees placement or replies.
When it sends you to the Free MCP
On every sizing result, for the case where the inboxes would replace ones whose results dropped.
“This sounds like a diagnostic issue. Check it with WarmInboxes Free MCP before replacing anything: a DNS, list or copy problem moves to new inboxes with you.” The WarmInboxes Free MCP
How the answers are worked out
- The diagnostic playbook: Including when replacing inboxes is warranted and when it is not.
- The infrastructure calculator: The same arithmetic, with every assumption on screen.
- Google or Azure for a list: How a list’s provider mix sets the two pools.
- Infrastructure recipes: Worked fleets for common volumes, checked against the planner at build time.
- Prices: The published prices every quote uses.
Questions
Is the WarmInboxes Free MCP: Fleet Planner free?
Yes. No account, no API key and no sign-in. A daily limit counted in distinct domains keeps it fair; re-checking a domain the same day is free.
Is it approved in the Claude and ChatGPT directories?
Not yet: it has not been submitted to either directory. Add it by its URL, https://warminboxes.com/mcp/planner, which works in Claude, ChatGPT, Grok and every other MCP client today.
How is it different from the Free MCP?
The Fleet Planner is a sizing-only view of WarmInboxes Free MCP, which finds out what is wrong. If results dropped, start with the full Free MCP: new inboxes do not fix a DNS, list or copy problem. Neither is WarmInboxes Infrastructure MCP, which places orders with an API key.
Can it buy inboxes?
No. Every tool is read-only. It works out what to order and what it costs; the first order is placed in the WarmInboxes app, and existing customers can connect WarmInboxes Infrastructure MCP from a client that sends an API key header.
What does it store?
Pasted headers, copy and CSVs are processed to answer and not stored. For the daily limit it keeps the domains checked that day, deleted within two days, and it counts sessions and tool calls anonymously, with no domain, IP or user id, for 90 days. The privacy policy has the detail.
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