Instantly MCP server
165 operations19 webhooks
Instantly API v2 for cold email - campaigns, subsequences and leads, the Unibox, sending accounts and warmup, inbox placement tests, email verification, the blocklist, webhooks and workspace admin.
Use Instantly in Claude, ChatGPT, Cursor or another MCP client
Connect Instantly once in Corsair, then add one MCP address to your agent.
Building your own app on the Corsair SDK? Get API keys
Connect Instantly to Claude, ChatGPT or Cursor
- 1
Connect Instantly in Corsair
Add your Instantly API key once in Corsair. Corsair stores the credential encrypted and makes the Instantly API calls for your agent, so it never goes into a prompt or a config file. Connect Instantly
If your link lets the agent add apps, you can skip this: it gives you a sign-in link the first time it needs Instantly. On a ChatGPT personal plan, connect Instantly here first.
- 2
Add Corsair's MCP server to your agent
Every client uses the same address:
https://mcp.corsair.dev/mcpClaude
Open Customize → Connectors → Add custom connector, paste the address, then select Connect.ChatGPT
Add a custom MCP server with the address and choose OAuth. Personal plans get read tools only.Cursor
Add to CursorOr add this to~/.cursor/mcp.json. Cursor opens Corsair to sign in the first time it connects.{ "mcpServers": { "corsair": { "url": "https://mcp.corsair.dev/mcp" } } }Claude Code
Run this, then run/mcpin Claude Code to sign in.claude mcp add --transport http corsair https://mcp.corsair.dev/mcpCodex, Gemini CLI, VS Code, Zed and other clients with OAuth sign-in work the same way. Clients without it, such as GitHub Copilot's coding agent, use a link's own address and an API key. Setup for every client
- 3
Sign in and choose what needs your approval
Your client opens Corsair to sign in. Pick a link: the apps your agent can use and a mode that decides what it may do without asking. In the default Cautious mode, Instantly's read and write operations run right away and its 27 destructive operations wait for your approval. Strict mode asks before every write and refuses destructive operations, and Read mode allows reads only.
Instantly operations available through MCP
- CreateWrite
Connect a sending account with its IMAP and SMTP login (Google and Microsoft OAuth connections are not covered by this plugin). The passwords are sent to Instantly and never logged
- DeleteDestructive
Remove a sending account from the workspace; it stops sending and warming up
- Disable WarmupWrite
Turn warmup off for up to 100 sending accounts (runs as a background job; returns the job)
- Enable WarmupWrite
Turn warmup on for up to 100 sending accounts (runs as a background job; returns the job)
- GetRead-only
Get one sending account by email address
- Get Daily AnalyticsRead-only
Emails sent per day by each sending account. Pass emails or a short date range: on a large workspace Instantly answers 413 otherwise
- Get Tracking Domain StatusRead-only
Check a custom tracking domain's DNS setup
- Get Warmup AnalyticsRead-only
Get warmup results for up to 100 sending accounts: daily sent, received and landed-in-inbox counts and a 0-100 health score
- ListRead-only
List sending accounts (mailboxes) with status, warmup status, daily limit and warmup score; filter by status, provider, tag or search
- List CampaignsRead-only
List the campaigns a sending account sends for
- Mark FixedWrite
Set a sending account back to active and clear its error message, after fixing its connection
- Move To WorkspaceWrite
Move sending accounts to another workspace in the same workspace group. Needs the admin workspace's API key
- PauseWrite
Pause a sending account: it stops sending campaign emails until resumed
- Pause ManyWrite
Pause up to 100 sending accounts at once; returns which were paused and which failed
- ResumeWrite
Resume a paused sending account so it sends campaign emails again
- Test VitalsRead-only
Check the health ("vitals") of sending accounts' domains; changes nothing
- UpdateWrite
Change a sending account's name, daily limit, sending gap, signature, reply-to, tracking domain or warmup settings
Instantly triggers
- Error
A sending account hit a connection or sending error
FAQ
Install corsair and @corsair-dev/instantly, add the Instantly plugin, and connect with an API key. Then call methods like corsair.instantly.api.accounts.create() from your app. Corsair verifies webhooks, and syncs data per tenant.
Yes. Instantly requires an API key from your Instantly account or developer dashboard. Create credentials with access that matches what you automate, then paste them into Corsair or connect through managed auth in Hub.
Yes. One Corsair client can hit Instantly, GitHub, Notion, Stripe, and the rest. Trigger Instantly from a webhook, push updates to Slack, or chain actions across plugins. Same tenant context across integrations, plain TypeScript.
Teams use Corsair for instantly api v2 for cold email - campaigns, subsequences and leads, the unibox, sending accounts and warmup, inbox placement tests, email verification, the blocklist, webhooks and workspace admin. Common builds include sync jobs, admin tooling, and agents that call Instantly APIs from your backend. Webhook handlers react to Instantly events and fan out to Slack, email, or other plugins in the same tenant. Local DB entities let you query synced Instantly records without hitting the API on every read.
The SDK is open source. Self-host and you pay Corsair nothing for the integration layer. Hub bills for hosted auth and execution, not per Instantly API call. Hub has a generous free tier. For hobby projects you can probably run the whole thing on free. Paid plans start to matter with more tenants or heavier traffic.
We maintain @corsair-dev/instantly in the open repo. When Instantly ships API changes, upgrade the package. Your call sites stay typed. You should not need to rewrite the integration layer each time.
No. Corsair does not read your Instantly data or hold individual access credentials. Credentials stay in your database. API calls run on your instance. We do not store Instantly data on your behalf.
Yes. Add https://mcp.corsair.dev/mcp as a custom connector or MCP server in Claude, ChatGPT, Cursor, VS Code, Claude Code, Codex or any client that supports remote MCP servers with OAuth sign-in, then sign in to Corsair. On ChatGPT personal plans, custom servers currently get read tools only.
Yes. Put Instantly on a link in Strict mode and every write waits for your approval, while destructive actions are refused. The default Cautious mode asks only before the 27 destructive Instantly operations. You can change a link's mode at hub.corsair.dev/me.