Adding email and calendar tools to an AI agent is mostly an exercise in restraint. Give it 50 commands and the agent gets confused. Give it 5 carefully-chosen ones and it punches above its weight. After running agents against the Nylas CLI for a few months, these are the five I keep coming back to. Each gets exposed via MCP (nylas mcp install) so the agent can call them directly. nylas email send The most-used tool by a wide margin. nylas email send \ --to [email protected] \ --subject "Re: budget review" \ --body "Approved. See you Friday." Why it ranks first: every agent task that touches the outside world eventually needs to communicate the result. A pull request shipped, an order placed, a bug filed — someone wants to know. Email is the lowest-common-denominator channel. Agent prompt pattern that works: When you complete a task that affects another person, send them an email summary. Use nylas email send with their address from the ticket. Subject line should match the ticket title. Body should be 2-3 sentences max. nylas email list --json Reading is half of email. The --json flag matters: agents parse JSON, not prose tables. nylas email list --unread --limit 20 --json | jq '.[] | {from: .from[0].email, subject, snippet}' Filters that matter most: --unread — only what is new --from "[email protected]" — scope to a sender --query "invoice" — text search across subject + body --in folder/Inbox — provider-specific folders A common pattern: every 5 minutes, the agent runs nylas email list --unread --json, sees 0-5 new messages, and decides whether each needs human attention. nylas calendar events list Most "schedule a meeting" requests fail because the agent does not know what is already on the calendar. Give it visibility. nylas calendar events list \ --start "2026-05-04T00:00:00Z" \ --end "2026-05-11T00:00:00Z" \ --json This returns a week of events as JSON the agent can reason over. Pair with nylas calendar find-time for "find a 30-minute slot when alice@ and bob@ are both free": nylas calendar find-time \ --participants [email protected],[email protected] \ --duration 30 \ --window-start "2026-05-04T09:00:00-05:00" \ --window-end "2026-05-08T17:00:00-05:00" nylas contacts search This one surprised me. The agent constantly needs the answer to "what is the email of the person whose name is X". Without contacts access, it asks the user. With contacts access, it just looks up. nylas contacts search --query "alice" --json Returns matches against name, email, and company. Three-letter queries work; the search is fuzzy. A specific pattern that pays off: when the agent drafts an email, it can run a contacts lookup on every name mentioned in the body to verify it has the right email. "Email Alice about the launch" without a contacts tool means asking which Alice. With the tool, the agent disambiguates by company or role. nylas agent account create For tasks that involve a new identity (testing flows, signing up for services, isolating per-PR test inboxes), the agent should be able to provision its own. nylas agent account create test-$(uuidgen)@yourapp.nylas.email --json Pair with nylas agent account delete to keep things tidy: nylas agent account delete $GRANT_ID --yes This is the meta-tool. The agent can spawn one-shot inboxes for E2E tests, signup automation, or cross-account verification. Most other "AI agents and email" stacks miss this primitive. Five more commands that are great but did not make the cut for a default agent install: Command Why excluded nylas email mark-starred Personal preference; agent has no opinion about importance nylas email delete Destructive; require human confirmation by default nylas calendar events create Powerful but easy to misuse — most teams want a human in the loop nylas webhook create Better as a one-time setup by the operator, not an agent action nylas agent rule create Same — policy and rules are operator-level config A safer agent surface is a smaller surface. Add commands as the agent earns trust. When the MCP install gives you the full tool set and you want to scope it down: // In your AI tool's MCP config, after running `nylas mcp install` { "mcpServers": { "nylas": { "command": "nylas", "args": ["mcp", "serve"], "env": { "NYLAS_MCP_TOOLS": "email_send,email_list,calendar_events_list,contacts_search,agent_account_create" } } } } The NYLAS_MCP_TOOLS env var allow-lists which tools the server exposes. Everything else stays hidden from the agent. The single biggest mistake I see in agent installs: throwing every available tool at the agent and hoping it picks. Better to start with five well-chosen ones and add more as the workflow demands. Send, list, calendar, contacts, agent-account — the five that cover 90% of real agent tasks involving email. Give your AI coding agent an email address — full MCP install for Claude Code, Cursor, Codex AI agent email MCP — MCP-specific setup walkthrough Build an LLM agent with email and calendar tools — broader pattern reference Full command reference