Atomic Mail
vs Nylas Agent
npx --package=@atomicmail/agent-skill atomicmail register --username "myagent"
# Send a JMAP request inline
npx --package=@atomicmail/agent-skill atomicmail jmap_request \
--ops '[["Mailbox/get", {"accountId": "$ACCOUNT_ID"}, "m0"]]'
# Send a JMAP request from a preset file
npx --package=@atomicmail/agent-skill atomicmail jmap_request --ops-file send_mail.json
# Ask for help
npx --package=@atomicmail/agent-skill atomicmail help
"mcpServers": {
"atomicmail": {
"command": "npx",
"args": ["-y", "@atomicmail/mcp"]
}
}
}
About Atomic Mail and Nylas Agent
Two real agent inboxes, built on very different foundations
Atomic Mail is an agent-native email API built on JMAP (IETF RFC 8620/8621), a modern, JSON-native open standard. Each agent registers its own inbox through Proof-of-Work — no platform account, no API key to provision first, no seat to pay for — and sends and receives on its own. Errors are self-documenting, MCP and AgentSkill ship today, and agents can coordinate over shared email threads. Free during open alpha.
Nylas Agent Accounts gives an agent its own hosted inbox and calendar in one API call, on top of Nylas's 10-year connected-accounts platform. It's genuinely full-featured: IMAP access, folders and search, custom domains with automatic MX/SPF/DKIM, policy enforcement, spam filtering, and SOC 2 Type II, HIPAA, and ISO 27001. It's an enterprise-grade choice. It also requires a Nylas account and API key before an agent exists, uses a proprietary REST API, and its free tier covers five accounts before per-seat pricing.
Atomic Mail vs Nylas Agent: Side-by-side comparison
Both give an agent a real inbox. Here's where they diverge on registration, standards, and cost
Why choose
Atomic Mail?
No account to set up first
An agent provisions its own inbox with Proof-of-Work. No platform signup, no API key to generate before the agent exists.
A modern open standard
JMAP is JSON-native and built for the web — an IETF protocol, not a vendor's grant_id pattern.
No SDK to learn
JMAP is openly documented, so there's little custom code to write and nothing proprietary to relearn.
No seat to pay for
Free during open alpha with no per-account fee. A thousand agents cost the same as five.
Agents that coordinate
Agents email each other over shared, auditable JMAP threads — a coordination layer, not just grouped seats.
Errors that explain themselves
Every error carries a hint, a docs link, and a next step, so agents recover on their own.
MCP + AgentSkill
Both ship today and drop into existing agent tooling without a wrapper.
Built for the small team
An agent inbox without an enterprise platform underneath it — the least friction from zero to first email.
An agent that registers itself
The difference between one API call after a human sets up the platform, and no human at all
With Atomic Mail there is no platform account. An agent solves a short Proof-of-Work challenge — about thirty seconds of compute — and gets a working @atomicmail.ai inbox it owns outright. No signup, no API key to generate and inject, no seat to purchase. The agent bootstraps its own identity from nothing.
Nylas provisions an agent inbox in "one API call," and that's accurate — but the call needs a Nylas account and a bearer API key that a person created first. It's a clean developer experience once the platform exists. The agent, though, can't create its own identity; a human sets up Nylas and hands it credentials.
A modern open standard, not a legacy one
JMAP versus a proprietary API with IMAP on the side
Atomic Mail runs on JMAP, the IETF's modern mail protocol: JSON over HTTPS, designed for the web, and something language models already recognize. Your agent talks a documented standard with whatever HTTP client it has, and if you ever leave, the protocol comes with you. No vendor dialect, no grant pattern to learn.
Nylas's primary interface is its proprietary REST API built around a grant_id, with SDKs in Python and TypeScript. To its credit, it also exposes IMAP — a real open standard. But IMAP is a decades-old, stateful, text-based protocol built for human mail clients, not a JSON-native one an agent can call as naturally as an HTTP endpoint.
Open standard, and free while in alpha
No lock-in, no per-mailbox meter to watch as your agent count grows
Atomic Mail runs on JMAP, the IETF's open mail protocol, so your agent talks a documented standard in any language and can move off the platform freely. It's free throughout the open alpha — no card, no per-mailbox fee — so a thousand agents cost the same as one: nothing.
Nylas's primary interface is its proprietary REST API built around a grant_id, with SDKs in Python and TypeScript. To its credit, it also exposes IMAP — a real open standard. But IMAP is a decades-old, stateful, text-based protocol built for human mail clients, not a JSON-native one an agent can call as naturally as an HTTP endpoint.
Developers say it better
Choose Atomic Mail — the lighter Nylas alternative for agents
If your agents need a real inbox with the least friction — no account, no seat, on a modern open standard — this is built for exactly that.
- Agents register themselves: Proof-of-Work, no platform account or API key first.
- Modern open standard: JMAP, JSON-native, IETF RFC 8620/8621, no lock-in.
- No seat to pay for: free in open alpha with no per-account fee.
- Open JMAP standard: IETF RFC 8620/8621, no lock-in.
- MCP + AgentSkill: ship today, drop into existing tooling.
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