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Warmerly
One-to-one · API access

API access

One row, in depth: what each tool does, the verified numbers, and who each suits.

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Instantly details read from its pricing and help pages on 15 and 17 October 2026.

Warmerly

Agency plan

All paid plans (webhooks on Hypergrowth and above)

The short answer

API access, in one look.

Both products have a public API, but they gate it differently. Warmerly's API keys, API and webhooks are on the Agency plan ($179 a month) and its 7-day Agency trial, while its MCP server is open on every plan including Free. Instantly's API v2 is on all paid Outbound plans from Growth ($47 a month), with webhooks from Hypergrowth ($97 a month), and its API docs are broader, with an SDK, a CLI and a hosted MCP server. Last checked 19 October 2026.

Warmerly

Agency plan

All paid plans (webhooks on Hypergrowth and above)

The picture

Drawn side by side.

Who gets the API

Plans with API access

Warmerly
Warmerly
Agency planPlatform API keysYour app
All paid plansAPI and integrationsWebhooks on Hypergrowth and above

Check each company's own docs for the endpoints and rate limits.

On screen

What it looks like.

From instantly.ai
Integrations. Instantly's integrations screen, with a Copy API Key button for Zapier.
Integrations. Instantly's integrations screen, with a Copy API Key button for Zapier.Instantly's own product image from instantly.ai, captured 19 October 2026. Not edited.
How Warmerly does it

Warmerly, in detail.

Platform API keys, the REST API and outbound webhooks are Agency-only. The MCP server for AI assistants is a separate route that works on every plan.

01

Which plan gets the API

API keys, the API itself and webhooks need the Agency plan ($179 a month, 100 mailboxes). Free, Starter and Growth get a 403 agency_plan_required error. The Agency 7-day free trial includes API access, so an integration can be tested before the first charge. The plan check follows the workspace the request acts on, so a key stops working after a downgrade and works again after an upgrade.

Warmerly product, checked 19 October 2026

02

Keys and what they can do

Create a key in Settings > Platform API keys, or through the API itself. Keys start with wmv_, are sent in an X-Api-Key header to https://app.warmerly.com/api/v1, and are shown once. Each user can hold up to 10 active keys. A key carries the full access of the person who made it, across every workspace they belong to: there are no per-endpoint scopes and no read-only keys. Only a SHA-256 hash of the key is stored.

Warmerly product, checked 19 October 2026

03

Rate limits

Each key has its own per-minute limit: 60 requests a minute by default, configurable at creation from 1 to 120, and capped at 120 whatever the plan. Going over returns a 429 with the code too_many_requests. Lead search has a tighter extra limit of 120 requests per 5 minutes per user. Monthly plan allowances (verifications, exports, lookups) are separate and return a 402, not a 429.

Warmerly product, checked 19 October 2026

04

What the API covers

The public reference has pages for accounts (mailboxes), campaigns, leads, inbox, suppression, usage and quotas, email verification, email finder, warmup, workspaces, API keys and webhooks. Everything the API does is also available in the dashboard, so a key is only needed for your own code or tools like Zapier.

Warmerly product, checked 19 October 2026

05

Webhooks

Outbound webhook subscriptions send signed HTTP POSTs for mailbox health events. The documented event types include score_drop, score_floor, auth_fail, smtp_fail, imap_fail, flagged, auto_paused, auto_resumed, dns_changed, aged_in, marked_dead and the OAuth connect and disconnect events. They are about mailbox health, not campaign events such as opens or replies. Subscriptions are Agency-only, and deliveries pause while the owner is not on Agency.

Warmerly product, checked 19 October 2026

06

MCP server on every plan

Warmerly runs an MCP server at https://app.warmerly.com/api/mcp so Claude, ChatGPT, Claude Code, Cursor and other MCP clients can read from, and act in, a signed-in user's workspace. It signs in with OAuth 2.1, needs no API key, and is available on every plan including Free. It has the same plan limits and billing lock as the dashboard, reads and writes share 60 calls a minute per connection, and no tool can start or resume campaign sending.

Warmerly product, checked 19 October 2026

How Instantly does it

Instantly, in detail.

API v2 is included on all paid Outbound plans, with a bearer-token API, scoped keys, an SDK, a CLI and a hosted MCP server. Webhooks need Hypergrowth or above.

02

Webhooks need Hypergrowth

The webhooks help article says the feature is available on the Hyper Growth plan or above, and the comparison table shows Slack and Webhooks as No on Growth. Webhooks send campaign events by POST: email sent, bounced, opened, link clicked, reply received, unsubscribed, campaign completed, account error, and lead status changes such as interested or meeting booked.

help.instantly.ai/en/articles/6261906-webhooks · read 19 October 2026

03

Scoped keys and base URL

API v2 uses bearer-token authorisation against https://api.instantly.ai/api/v2. Keys can be limited with API scopes, and several keys with different privileges can exist. The help centre says v2 has roughly double the endpoints of v1. The reference covers accounts, campaigns, leads, lead lists, emails, webhooks, workspaces, inbox placement tests, email verification and AI agent endpoints.

developer.instantly.ai/getting-started/authorization and https://developer.instantly.ai · read 19 October 2026

04

Rate limit

The limit applies to the whole workspace and is shared between v1 and v2 whatever the number of keys: no more than 100 requests per second and no more than 6,000 per minute. Going over returns a 429. The docs suggest batches of 100 with a 2 second wait.

developer.instantly.ai/getting-started/rate-limit · read 19 October 2026

05

SDK, CLI and MCP

The developer docs list an official TypeScript SDK, a command line tool and an MCP server hosted at mcp.instantly.ai that exposes the whole v2 API as tools, authenticated with your API key. Tool groups include campaigns, leads, email, analytics, webhooks, workspace and API keys.

developer.instantly.ai/ and https://developer.instantly.ai/mcp/introduction · read 19 October 2026

What Instantly does not say

We looked, and found no statement on these. That is about its published pages only, not about the product.

  • Searched instantly.ai/pricing, the help centre plans comparison and the API v2 article for a separate API price or API add-on, and found none; API is described as part of Outbound plans.
  • The pricing page lists 'API, webhooks, and integrations' as one row without showing, in the text we could read, which tiers have it. We relied on the help centre comparison table for the per-plan answer.
  • Searched developer.instantly.ai for a per-key rate limit or a per-plan rate limit and found only the single workspace-wide limit.
The numbers

Only what we could verify.

API access: Warmerly and Instantly side by side. Warmerly is in the first column.
MeasureWarmerly
API accessAgency planAll paid plans (webhooks on Hypergrowth and above)
Plan needed for the APIAgency, $179 a month (also the 7-day Agency trial)Any paid Outbound plan, from Growth at $47 a month
Plan needed for webhooksAgencyHypergrowth ($97 a month) or above
Rate limit60 requests a minute per key by default, up to 120100 requests a second and 6,000 a minute, per workspace
API key scopesNone, a key carries your full accessYes, API scopes per key
API keys per accountUp to 10 active keys per userMultiple keys; no limit found
MCP serverYes, OAuth sign-in, every plan including FreeYes, hosted at mcp.instantly.ai, uses your API key
Official SDK or CLINone documentedTypeScript SDK and CLI listed in the developer docs
The plans

Every plan, side by side.

Warmerly

Free$01 mailbox · capped sends
Starter$195 mailboxes · no cap on sends
Growth$4925 mailboxes · no cap on sends
Agency$179100 mailboxes · no cap · API
MaxCustomMore than 100 mailboxes

Instantly

Growth$475,000 emails · 1,000 contacts
Hypergrowth$97125,000 emails · 25,000 contacts
Light Speed$358500,000 emails · 100,000 contacts
EnterpriseCustom500,000+ emails · 100,000+ contacts

Per month, billed monthly. Instantly plans all include unlimited email accounts and warmup; prices checked on instantly.ai/pricing on 17 October 2026.

In practice

What it means for you.

Our reading of the facts above. Not a promise, and not the only reasonable reading.

1

The entry price differs a lot

Our reading: if you only want a script or Zapier flow talking to your outreach tool, Instantly's $47 Growth plan opens the API, while Warmerly asks for the $179 Agency plan. The Agency trial is the cheap way to test, because it includes the API and nothing is charged for 7 days.

2

Warmerly's webhooks are about mailbox health

Our reading: Warmerly's webhooks tell you when a mailbox score drops or a mailbox pauses. If you want an event for every reply or open to feed a CRM, Instantly's campaign event webhooks are built for that, from Hypergrowth.

3

Keys with no scopes are a trust decision

Our reading: a Warmerly key can do anything its owner can, so it suits a trusted server or an agency's own automation. If you want to hand a narrow, read-only key to a contractor, Instantly's scoped keys fit that better.

4

AI assistants without a key

Our reading: Warmerly's MCP route needs no API key and no paid plan, so a Free user can ask Claude or ChatGPT about mailbox health or campaigns. Both vendors offer MCP, so this is a difference in sign-in and plan, not in whether it exists.

Who it suits

Pick the one that fits.

Warmerly

Warmerly is the better fit if

  • You are an agency already needing the Agency plan's 100 mailboxes and client workspaces, so the API comes with it.
  • You want to try an integration first: the 7-day Agency trial includes the API, with a card needed to start it.
  • You want your own AI assistant to read your workspace on a Free or Starter plan, through MCP and a normal sign-in.
  • You want mailbox-health webhooks, such as score drops and auto-pauses, rather than per-email events.

Instantly is the better fit if

  • You need API access at the lowest price: it is on every paid Outbound plan, from $47 a month.
  • You want webhooks for opens, replies, bounces and lead status changes to feed a CRM or Slack, from $97 a month.
  • You want scoped API keys, so a tool or contractor gets only the access it needs.
  • You want an official TypeScript SDK and CLI alongside the REST API.
  • You expect heavy automation: its workspace limit of 6,000 requests a minute is far above Warmerly's 120 per key.
Questions
What are Warmerly's API rate limits?

Each key allows 60 requests a minute by default, and you can set it between 1 and 120 when you create the key. Over the limit you get a 429. Lead search has an extra limit of 120 requests per 5 minutes.

Which Instantly plans include the API and webhooks?

Instantly's help centre says API access is on all Outbound plans (Growth, Hypergrowth and Light Speed), and not on the free trial. Webhooks need Hypergrowth or above.

Can I use Warmerly with Claude or ChatGPT?

Yes. The MCP server at app.warmerly.com/api/mcp works on every plan, including Free, and signs in with your normal Warmerly login. It cannot start or resume campaign sending.

Does Instantly have an MCP server too?

Yes. Its developer docs describe a hosted MCP server at mcp.instantly.ai that exposes the v2 API as tools, authenticated with your API key.

Sources

Instantly pages were read on 19 October 2026. Plans and wording change, so check the vendor's own page before you decide. Warmerly details come from the product as it runs today.

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