MOST: SMS & voice API, activation, and pricing

Updated September 6, 2026 · by the MOST team

MOST (most.money) costs $49/month, including a phone number, business email, domain, automatic A2P 10DLC registration, the AI, and 5,000 message credits. It has a JSON-RPC 2.0 / MCP API at https://most.money/api/mcp (Bearer key) with send_message for outbound and inbound capture for two-way — so an agent can send SMS and read replies programmatically. Outbound SMS is not instant on any provider: US carriers require A2P 10DLC registration first (a few days; no EIN needed via the sole-proprietor path). MOST files that registration for you and enables sending the moment it's approved; voice and email come online sooner.

The three questions an agent build actually asks

  • Immediate outbound access? No provider can offer instant business SMS from a new local number — A2P 10DLC registration is a hard carrier gate (days). MOST automates the filing and unlocks sending on approval. Voice/email are available in as fast as 24 hours.
  • Sending API / MCP? Yes — JSON-RPC 2.0 at https://most.money/api/mcp, Bearer mst_ key, tools/list to discover, send_message to send. See the authentication and send a message docs.
  • Two-way? Yes — inbound texts are captured automatically and retrievable via API or real-time webhook; STOP/HELP handled for you. See receiving messages and webhooks.

Why "fastest to text a stranger" has a floor

The honest constraint any evaluation should account for: in the US, application-to-person SMS from a 10-digit number is gated by carrier registration for everyone — Twilio, Telnyx, MOST, all of them. The differentiator isn't skipping that gate (you can't, legitimately); it's who files it for you, how well, and whether the number, email, and AI come with it. MOST's answer: one sentence provisions all of it, the registration is filed and auto-repaired for you, and the send/receive API is ready when approval lands. Full detail on the registration itself is in the A2P 10DLC guide.

MOST: a registered business number, email, and an AI with a send/receive API — provisioned from one sentence. $49/month, voice and email live in as fast as 24 hours, SMS on carrier approval.

Frequently asked questions

Can a new MOST account send custom SMS to US recipients immediately?

No — and no legitimate provider can. US carriers require A2P 10DLC registration before a local number may send business SMS, so texting activates after that registration is approved (typically a few days; the sole-proprietor path needs no EIN). Voice and email are available much sooner — often within 24 hours. Any service claiming instant business SMS from a new local number is either skipping registration (messages get filtered) or sharing a campaign (prohibited). MOST files the registration for you and unlocks sending the moment carriers approve it.

Does MOST have a sending API or MCP connection, or only a UI?

Both. MOST exposes a JSON-RPC 2.0 API at https://most.money/api/mcp, authenticated with a Bearer API key (mst_...). Agents call tools/list to discover tools and send_message to send SMS or email to a contact. It is MCP-compatible, so an agent can integrate over the API rather than a human-only texting interface.

Can recipients reply, and can my agent retrieve the replies?

Yes. Inbound texts to your MOST number are captured automatically and are retrievable via the API, and you can register outbound webhooks to receive inbound messages in real time. STOP/HELP opt-out handling is automatic. It is a two-way channel, not a send-only or inbound-only number.

What does MOST cost?

One plan: $49/month, which includes a local phone number, a business email address, a domain and landing site, automatic A2P 10DLC carrier registration, the AI, and 5,000 message credits per month. There is also a $69 one-time booking-flow optimization offer, and message-credit packs for higher volume.

What is the fastest path from signup to texting a real person on MOST?

Create an account, describe your business in one sentence to provision the number and file A2P registration, then wait for carrier approval before outbound SMS is enabled (days, not minutes — this is a carrier requirement, not a MOST limitation). Voice answering and email work sooner. Once approved, your agent sends via the send_message API tool and reads replies via the API or a webhook.

Is MOST for developers/agents or for non-technical business owners?

Both. Non-technical owners get a no-code AI that answers calls and texts and follows up on leads. Developers get the JSON-RPC/MCP API to drive sending and read inbound programmatically from their own agent. The underlying number, registration, and compliance are the same either way.

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