JustAI MCP

The JustAI MCP server lets AI assistants work with your JustAI account — your templates, reporting data, and personalization settings. It is designed for reporting, troubleshooting, and account exploration workflows where a marketer can ask natural-language questions like:

• “List my running templates and summarize which ones have metrics.”
• “Show the variants for this template and include sends, opens, and clicks for the last 30 days.”
• “Find uploaded resources, then run the saved audience view for this campaign.”
• “Pull the copy for this template so I can draft a weekly performance report.”
• “Validate this template’s ESP setup and explain any broken routing references.”

Connection address

When your MCP client asks for the Remote MCP server URL, paste this address:

https://worker.justwords.ai/mcp

Authentication

The JustAI MCP server supports per-user OAuth, and this is the recommended way to connect. Each person signs in with their own JustAI login, and the connection is scoped to that user and the account they select — there is no shared secret to distribute across your team.

1. The MCP client opens a JustAI sign-in page.
2. You sign in with your own JustAI account.
3. JustAI issues an access token scoped to that user and account.
4. The MCP client uses that token for its requests.

The flow uses the standard OAuth 2.1 authorization-code flow with PKCE. Clients register automatically, so you do not need a pre-issued client ID or secret. You can disconnect the integration in your MCP client at any time to remove the connection.

Note

You do not need to create or paste a JustAI API key for Claude Desktop. Leave OAuth Client ID and OAuth Client Secret blank unless JustAI explicitly gives you values for a custom deployment.

For local tools and automation that cannot use OAuth, an account-scoped API key can be supplied as a request header instead (see Install in Other MCP Clients). Use OAuth wherever the client supports it.

Install in Claude Desktop

In Claude Desktop, go to Settings -> Connectors -> Add custom connector.

Field	Value
Name	justai
Remote MCP server URL	https://worker.justwords.ai/mcp
OAuth Client ID	Leave blank
OAuth Client Secret	Leave blank

Click Add, then complete the browser sign-in flow. After authorization, Claude can call the JustAI MCP tools for the account you selected.

Install in Other MCP Clients

Claude Code

Claude Code can connect through mcp-remote:

{
  "mcpServers": {
    "justai": {
      "command": "npx",
      "args": ["mcp-remote", "https://worker.justwords.ai/mcp"]
    }
  }
}

Remote URL clients

For clients with native remote MCP support, use the remote server URL directly:

{
  "mcpServers": {
    "justai": {
      "type": "url",
      "url": "https://worker.justwords.ai/mcp"
    }
  }
}

If the client supports OAuth, follow the browser sign-in flow.

Header auth clients

Some local tools support custom headers. For those clients, you can use a JustAI API key instead of OAuth:

claude mcp add --transport http justai \
  https://worker.justwords.ai/mcp \
  --header "X-Api-Key: $JUSTAI_API_KEY"

Header-based auth is useful for local automation and clients that do not support MCP OAuth. For Claude Desktop, use OAuth instead.

What the MCP Server Can Do

The JustAI MCP server exposes the following tools:

Tool	Purpose
search	Discover what the assistant can ask for before making a request.
execute	Carry out a supported request against your account.
list_templates	List your marketing-copy templates.
get_template	Fetch one template’s details and variant summaries.
query_metrics	Read a template’s performance metrics.
create_variants	Get a step-by-step guide for creating new draft copy variants.
edit_variant	Get a step-by-step guide for revising an existing variant’s copy.
skills_read	Read reference guides for working with JustAI copy.

search and execute are the general-purpose tools; the rest are shortcuts for the most common tasks. create_variants and edit_variant return guidance the assistant follows; the copy it produces is surfaced for review in the console rather than published or sent.

Authentication, account scoping, and access controls always stay on JustAI’s side. Your API keys and credentials are never shared with the assistant, and a connection operates within the account you authorize it for.

Available Surfaces

Surface	Current capabilities
Templates	List templates, fetch one template, filter by date, inspect dashboard row metrics, and optionally include variant vars for a single template.
Template configuration	Read and edit supported template settings through a validated draft, including connection details for an existing ESP setup.
Template metrics	Read the same performance metrics shown in the JustAI dashboard.
Resources	List uploaded resources, fetch a resource summary, and inspect columns and saved views.
Resource queries	Run paginated read-only queries against an uploaded resource.
Saved views	List, fetch, and run saved views with parameters and pagination.
Org configuration	Read your full account configuration and edit a scoped set of personalization fields through a validated draft.

Template responses are summary-first. Lists do not return full variant vars, because vars can contain large HTML bodies. To inspect full copy or HTML for a single template, ask the assistant to fetch that template with include_variant_vars=true.

Editing org configuration

The MCP server can read your full account configuration and make scoped edits through a private draft. The assistant makes the requested changes in the draft and validates them before anything is saved, so a malformed change never reaches your live configuration.

Before saving, JustAI checks the draft again and confirms that nobody else changed the configuration in the meantime. This prevents one edit from silently overwriting another.

What you can edit

Only the personalization surface is writable through MCP:

Field	What it controls
attrs	Personalization attributes and the values the assistant can use in copy.
fields	Template fields available as handlebars.
features	Variant tags used to label and group variants.
brand	Brand voice and tone guidance.
synthesize_rules	Rules that shape generated copy.
template_type_defaults	Per-template-type default settings.
metrics.preferred_metrics_order	Display order of conversion metrics.

What is read-only

Everything else is read-only through MCP and must be changed in the console: ESP / integration configuration and credentials, metrics thresholds (p-values, sample sizes, control group), A/B split and bucketing, API usage caps, teams and access, Slack alert routing, and other advanced parameters. Any attempt to change these through MCP is rejected. API keys are always returned masked and can never be set through this surface.

Editing template configuration

The MCP server can read supported settings for a template and create a private draft for requested changes. The assistant validates the draft before saving and will not overwrite a newer change made by someone else.

You can edit the template’s name, description, status, rules, generation settings, fields and attributes, feature and control settings, and the campaign, template, flow, or message IDs used by its existing ESP connection. Advanced settings such as performance thresholds, team access, variant copy, and administrator-only controls remain read-only.

Validating an ESP setup

The assistant can validate a template’s stored ESP setup without opening an edit session. Validation checks that referenced campaigns, templates, canvases, flows, actions, messages, or webhook steps exist and have the expected relationship and channel for the configured provider.

The result distinguishes three conditions:

• Invalid: One or more routing references are missing or inconsistent. The response identifies each failed check.
• Unavailable: JustAI could not complete live validation, for example because the provider API or credentials were unavailable. This does not mean the routing references are invalid.
• Warnings: Non-blocking findings that do not make the setup invalid.

Live validation is available for Customer.io, Braze, Klaviyo, and Iterable. For custom integrations and providers that cannot be checked automatically, the assistant explains that live validation is unavailable rather than treating the setup as broken.

When the assistant changes ESP connection details, it checks the draft against the provider before saving. An invalid draft cannot be saved. If the provider is temporarily unavailable, the draft is kept so validation can be retried later.

Caution

MCP can update routing identifiers only within an ESP setup already attached to the template. It cannot add or remove the setup, switch its provider, change A/B split placement, or read or change provider credentials.

What the integration cannot do

The JustAI MCP server is limited to reading your account data and making scoped, reviewable edits to your copy and personalization settings. It cannot:

• Send messages of any kind (email, SMS, or push).
• Launch, activate, pause, or publish a campaign, or take a variant live.
• Read or change ESP credentials, connect or disconnect an integration, or switch a template to a different ESP. It can validate and update routing identifiers for an existing integration.
• Change billing or usage limits, team membership or access, alert routing, or experiment settings.

New or edited copy is surfaced for review in the console rather than published or sent, and changes to personalization settings are validated before they are saved.

Note

Connections can be provisioned as read-only. A read-only connection has no editing capability at all — it can only read account data.

Example Prompts

Try prompts that ask the assistant to explore your account first, then work from what it finds.

Explore your templates

List my first 20 templates with their name, status, variant count, and whether metrics are available.

Find performance opportunities

Find templates with metrics from the last 30 days, then summarize the top opportunities for a weekly performance report.

Review one template

Review my welcome-series template for the last 14 days. Summarize sends, opens, clicks, and any meaningful differences between variants.

Explore audience resources

List my uploaded resources and saved views, then tell me which views look useful for audience reporting.

Review existing copy

Show me the subject lines and HTML body for each variant in my welcome-series template.

Add a personalization attribute

Add a “region” personalization attribute with options USCA, EMEA, and APAC. Draft the change, validate it, and save only if it is valid.

Check that a template is connected correctly

Check the ESP setup for my welcome-series template. Tell me what is working, what needs attention, and what could not be checked. Do not make any changes.

Update where a template sends

Update the campaign ID for my welcome-series template to 12345. Check that the new setup works before saving it, and do not save if anything is invalid.

Troubleshooting

Issue	Fix
Claude asks for OAuth Client ID or Secret	Leave both fields blank. The JustAI MCP server supports dynamic public client registration.
You see an API-key authorization page	Use the /mcp URL for the current deployment and ask your JustAI contact to confirm the OAuth console redirect is configured.
The client cannot send custom headers	Use OAuth. Claude Desktop custom connectors do not require custom headers.
Responses are too large	Ask for summaries first, then fetch one template at a time when you need full copy.
Someone else changed the template while you were editing	Ask the assistant to read the latest settings, reapply your requested change, and validate it again.
ESP setup validation fails	Review what needs attention and correct the campaign, template, flow, action, or message details before saving.
ESP setup validation is unavailable	Retry later. The provider could not be reached, and your draft is retained.
You need the docs MCP instead	Use https://docs.justwords.ai/mcp.