App builderCompatible per the specificationChecked on 10/28/2026

Connect Bolt to Postal

Add Postal as a custom Bolt connector to look up and send emails while you build your project.

How you sign in: Account or key
Transport: HTTP
Recommended access: Read and send

Before you start

Check these points before opening the Bolt setup. They prevent most connection failures.

A team with the "MCP server" plan feature (mcp_access); without it the server responds 403 plan_limit_reached.
To send emails, the team needs at least one verified domain.
If you will use an API key: create the key in the dashboard, under API keys. It starts with ps_; a send-only key is enough if you will only send.
Each connection acts on a single team. To use another team, connect again and pick the other one.
Connections are listed under Settings › AI connections in the dashboard, where they can be revoked at any time.

What Bolt requires

Choose the HTTP transport, not SSE. Many connectors can slow Bolt down and use more tokens (a warning from its own documentation). The documentation does not state a plan or version.

Connect

Follow the steps in order. The server address is always https://api.postal.so/mcp. Recommended path: sign in with your account (OAuth). The API key is the alternative. Wherever ps_... appears, use your own API key: the value shown is only an example.

1
In the Bolt chat, click the + icon, then Connectors and Manage connectors.
2
On the Connectors (MCP) page, click "Custom MCP server".
3
Enter a name, the URL https://api.postal.so/mcp, the HTTP transport type and MCP OAuth authentication.
4
Click Connect, finish the Postal login (choose the team and click Allow) and wait for the "Connected" status. Optional: turn on "Auto-enable for all projects".
5
Alternative without OAuth: API key authentication, pasting a Postal API key (ps_...).

Server URL

Text

https://api.postal.so/mcp

Access the tool needs

Postal splits access into three levels, explained in the scopes table. For Bolt:

Required

Read your datamcp:read

View emails, domains, contacts, segments, topics, templates, broadcasts, automations, forms, inbox conversations, metrics and usage.

Recommended

Send emails and eventsmcp:send

Send and schedule emails from verified domains and record events for automations.

For Bolt to look up domains and templates (mcp:read) and send a test email (mcp:send). All of the connector's tools are enabled by default in Bolt and apply to all projects; avoid mcp:full and, if possible, use a sending_access key.

How to confirm it worked

The simplest proof is to ask for something read-only inside Bolt itself. The connection also shows up under Settings › AI connections in the Postal dashboard, with the app, the team and the last use.

Illustrative example

List my domains on Postal.

I found 2 domains on the Aurora Cosméticos team: exemplo.com.br (verified) and loja.exemplo.com.br (verifying).

For those who want the technical proof

Terminal: tool list with an API key

npx @modelcontextprotocol/inspector --cli https://api.postal.so/mcp \
  --transport http \
  --header "Authorization: Bearer ps_..." \
  --method tools/list

34Tools expected with a full-access key

The Inspector proves that the Postal server responds. It does not test Bolt itself. The full walkthrough is in Validate the connection.

If something goes wrong

Go through the list in order. Then read what we know (and what we don't know) about Bolt.

Check

The address is exactly https://api.postal.so/mcp, with /mcp at the end.
The connection type is HTTP (Streamable HTTP). Postal does not offer SSE: if the tool gives you the choice, use HTTP.
The team has the "MCP server" feature on its plan. Without it, the server responds 403 plan_limit_reached.
To send emails, the team has at least one verified domain.
Each connection acts on a single team. To use another one, connect again and pick the other.
429 response (rate_limit_exceeded): the plan's requests-per-second limit was reached. Wait a moment and try again.
If the tool complains about the response size, ask for smaller lists (at most 100 items per call; the default is 20).
To start over from scratch, revoke the connection under Settings › AI connections and connect again.

What was tested and what was not

Compatible per the specificationChecked on 10/28/2026

We followed the app's specification and documentation, but have not yet tested with the real app. Below is the full note on what was and was not verified.

Test details

Bolt's documentation offers the transport types "HTTP" (default) and "SSE" and the authentication methods API key, MCP OAuth and None, but it does not mention OAuth callback URLs, plans or limits. Postal only offers Streamable HTTP, which is what Bolt calls HTTP; the SSE option does not work with Postal. The API key path was verified with the SDK; OAuth is the standard flow with dynamic registration, not tested with the real Bolt.

Frequently asked questions

Do I need an API key to connect Bolt?

Not required. Bolt can sign in with your Postal account (OAuth) or with an API key. Recommended path: sign in with your account (OAuth). The API key is the alternative. The send-only key (sending_access) exposes only send_email and track_event.

Can I limit what Bolt does on my account?

Official Bolt documentation Postal MCP server Authentication and keys All tools

Keep going

Other tools

Each tool has its own walkthrough. See also the full list under AI.

Ready to use Postal in Bolt?

Create your account and connect. If you need help, talk to us through the contact form.

Create account See all tools