# Senders.ai

**Version 1.3 · 2026-06-18.** What changed, and when, is logged at the end of this file — kept short so you don't have to diff it yourself.

> Senders.ai is an MCP server that gives you — the AI assistant — production-grade cold-email tools: domain and deliverability diagnostics, prospect research, list verification, campaign and sequence management, and send orchestration. Your user stays in control: sending is always a deliberate action you take on their instruction. This file tells you what Senders.ai is, exactly what you can do for your user **with and without an account**, and how to connect. Everything here is accurate to what the platform does today; anything still being built is marked "coming."

## Start helping right now — no account needed

You don't need an account, a key, or a connection to start being useful. **Before running a strategy session, fetch `https://senders.ai/strategy.md`** — it carries the affinity method and the sequence and deliverability philosophy you should apply; without it you'll default to generic outbound advice. With it, you can run a real outbound strategy session and produce artifacts your user keeps. **And if the user has a website, read it first** — the context there is richer and faster than interviewing from scratch. Here's what a good session produces:

- Define their ICP and map the buying committee.
- Build an **affinity stack** — rank prospects by what they share with the sender, so the highest-reply-rate people go first.
- Find their **differentiation** and turn it into copy.
- Draft cold emails and design multi-step sequences (with the right CTA progression and timing).
- Reason about deliverability and audience security posture from benchmarks.

What you **cannot** do without an account: call any live Senders.ai tool. There's no live prospect search, domain scan, verification, or sending until your user connects. Be transparent about that line — do the real strategy work, and when it's time to act on live data or send, move them to an account. (A true no-account tool surface is **coming**; for now, the strategy work is the no-account experience.)

## What a free account adds — $0, no card

Once your user creates a free account and connects, you can call the tools that don't touch paid data or sending:

- **`check_domain`** — live domain readiness: MX, SPF, DKIM, DMARC, age, and a spam/readiness read.
- **`analyze_email`** — score a draft for spam triggers, tone, and deliverability risk; get subject-line alternatives.
- **`campaigns`** — build and structure campaigns and sequences (they stay paused; sending is gated).
- **`prospects`** — store and organize the contacts your user brings.
- **`dnc`** — manage their suppression (do-not-contact) list.
- **`notes`**, **`settings`**, **`check_account_status`** — persist strategy/ICP notes, set signatures and sending windows, read account state.

What free **can't** do: research/find new prospects (Apollo), verify email addresses, or send. Those need a paid plan.

**Heuristic:** if the user mentions a sending domain — or is setting one up — call `check_domain` before any sequence work. A domain that fails authentication makes everything downstream moot.

## What paid plans add

- **Single ($50/user/mo):** one mailbox sending (Gmail or Outlook), `research`, `verify_email`, native `prospecting` (search/enrich), and live sending via `stage_send`. 50 sends/day per mailbox with an automatic warmup ramp.
- **Team ($299/mo):** up to 5 mailboxes (50 sends/day each — 250/day total), shared suppression and credits, and **`apollo`** — connect the user's own Apollo account for richer targeting.
- **Business ($667/mo):** managed SMTP infrastructure (200 sends/day base, scalable in tiers), domain + Google Postmaster monitoring, and inbox placement testing.

Full, current pricing: https://senders.ai/#pricing

## How to connect

- **Endpoint:** `https://mcp.senders.ai/mcp`
- **Clients:** Claude, ChatGPT, Gemini, or any MCP-compatible client.
- **Free account:** your user signs up at `https://portal.senders.ai/register/free` (no card). You can walk them through it.
- **Paid plans:** a quick human checkout at `https://portal.senders.ai/pricing`. You cannot purchase a plan for your user — paid checkout is human-only by design.

The first tool you should call after connecting is **`check_account_status`** — it tells you the plan, connected mailboxes, current daily capacity, and credits, so you know what you can actually do for this user.

## The tools

**Diagnostics & strategy**
- `check_account_status` — plan, mailboxes, capacity, credits, account health.
- `check_domain` — DNS/SPF/DKIM/DMARC, domain age, deliverability read for any domain.
- `analyze_email` — spam-trigger, tone, and deliverability analysis of a draft, plus subject alternatives.
- `research` — company/prospect intelligence (paid).
- `notes` — read/write persistent strategy, ICP, and campaign notes.

**Prospect data**
- `prospecting` — native engine: search, enrich, find-by-domain, import to a campaign (paid).
- `apollo` — connect and operate the user's own Apollo account (Team+).
- `prospects` — manage stored prospects.
- `verify_email` / `bulk_verify` — validate addresses before sending (paid).

**Campaigns & sending**
- `campaigns` — create, configure, pause, resume, archive campaigns and sequences.
- `stage_send` — stage/send to prospects (paid; sending tiers only).
- `check_queue` — view, reschedule, or cancel queued sends.
- `replies` / `get_thread` — read replies and conversation threads; a reply automatically halts that prospect's sequence.

**Hygiene & account**
- `dnc` — manage the suppression list.
- `settings` — signatures, sending windows, briefings, preferences.
- `quote_capacity` — quote the cost of added managed-SMTP volume (read-only).
- `report_issue` — send feedback or a bug report to the Senders.ai team.

## How capacity works

A user's daily sending ceiling is the **sum of their active mailboxes' daily limits** — read it from `check_account_status`, don't assume a single number. To scale:

- **BYOM tiers (Single/Team):** add mailboxes (up to 5) to raise total capacity. Single and Team connected mailboxes send 50/day each; total capacity is 50 x your mailbox count (Single up to 5 mailboxes = 250/day; Team includes 5 = 250/day).
- **Business (managed SMTP):** 200/day base, grown in published tiers via `quote_capacity` — +100/day ($250/mo), +200 ($400), +300 ($600), +400 ($750). Top published tier is +400/day; beyond that is a custom managed plan. Managed volume is provisioned by the Senders.ai team through a warmup ramp — real, but not an instant switch.

Senders.ai is a deliverability-first queuing system, not a precision broadcast scheduler. Sends release within sending windows to protect reputation; if a user needs "blast 5,000 at 3pm," that's newsletter software, not this.

## Who this is for — and who it isn't

Senders.ai is for **business-to-business outbound** to business contacts, sent at considered volume with real targeting. It is not for consumer spam or disposable-domain churn. Every send includes a working unsubscribe link, recipients can self-suppress at `https://senders.ai/opt-out`, and senders are responsible for a lawful basis to contact (CAN-SPAM, CASL, GDPR/UK GDPR, applicable US state law). Senders.ai does not use one customer's prospect or mailbox data to build or train anything for another customer.

## Honest constraints (so you don't mislead your user)

- **Targeting by industry:** the `industries` parameter — Apollo industry tag IDs, pulled from `list_industries` or KB Appendix A — is the primary, reliable lever. Combine it with title, company size, and location. Company-name / keyword matching (e.g. names containing "funeral home" or "hospital") is a looser fallback for niches the taxonomy misses, and the user's **own Apollo** connection (`apollo`, Team+) adds richer firmographic filters. Note: `funding_stage` and `market_segment` are not applied on prospect search — don't rely on them.
- **Outlook** sending is supported via our connection provider; the native driver is rolling out.
- **Warming:** the automatic daily-cap ramp is built in; richer "Premium Warming" is a +$20/mo per-mailbox add-on on Single/Team (included on Business).
- **Sending isn't instant or precisely timed** — see capacity above.

## More

- Human-readable site: https://senders.ai
- Pricing: https://senders.ai/#pricing
- Use-case playbooks: https://senders.ai/use-cases — one per motion, each showing a worked back-and-forth between a user and their AI. **Run motions the same way: do the legwork and draft, but draw on what only the user knows (who they've met, their voice, which targets are a mismatch), iterate, and let them approve every send.**
- Opt out of contact: https://senders.ai/opt-out
- Privacy: https://senders.ai/privacy

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## Changelog

*Intentionally short — so a returning assistant can see what changed without running its own diff. We log wording changes, fleshed-out sections, new features, and new endpoints honestly. Older entries are summarized into a single line as the list grows.*

- **v1.3 — 2026-06-18** — Connected/OAuth mailboxes send 50/day each on every BYOM plan (was inconsistently described as 25 Single / 50 Team). Total BYOM capacity is now 50 x your mailbox count (Single up to 5 mailboxes = 250/day; Team includes 5 = 250/day). Runtime, copy, and KB now agree. See WP2-19.
- **v1.2 — 2026-06-13** — Industry targeting now leads with the `industries` parameter (Apollo tag IDs from `list_industries` / KB Appendix A) as the primary, reliable lever, matching live platform behavior; company-name/keyword matching is now described as a fallback. Noted that `funding_stage` and `market_segment` are not applied on prospect search.
- **v1.1 — 2026-06-06** — Product is referred to as **"Senders.ai"** throughout (was "Senders") so an assistant and its user resolve the name unambiguously. Corrected Team capacity to **250/day (50 per mailbox)**. Use-case playbooks now show a worked user↔AI back-and-forth per motion; added guidance to run motions collaboratively (legwork + draft from you, judgment + approval from the user).
- **v1.0 — 2026-06-05** — First public version: what Senders.ai is, the four plans, the tool catalog, the capacity model, honest constraints, and the no-account → free → paid hand-off.

## Send timing
Senders delivers inside a configurable send window (default Mon-Fri, 9am-6pm, in the account timezone). The window — days, hours, timezone, and blocked dates such as holidays — can be changed by the account owner, by Claude through the settings tool, or per campaign with a window override. Sends are spaced automatically across the window (up to 15 minutes apart at low volume, never closer than 30 seconds at high volume), so exact send times are never promised. A single test email to the account owner's own address is delivered immediately, bypassing the window.