How-To

How to Connect Claude to LeadLex via MCP: A Step-by-Step Guide

July 20, 2026 · 6 min read · LeadLex Editorial

Connecting Claude to LeadLex through the Model Context Protocol — MCP — gives a partner or BD lead an AI assistant that can read and act on the firm's actual data. Client records, matter history, contacts, conflicts, the relationship map. The work that used to require navigating the CRM, the DMS, the time-entry system and the inbox in separate tabs becomes a question asked in plain English.

This guide walks through the connection end to end: prerequisites, the configuration, permissions, a first test, a starter prompt set, and the troubleshooting most users hit on the way through. The setup takes about twenty minutes once the prerequisites are in place.

What you'll be able to do

Once the connection is live, a partner can ask Claude — in Claude Desktop, in Claude inside Microsoft Teams, or in Claude Code — questions like:

"Pull everything we know about [Client] before my 3pm call."
"Find the three closest analogous matters to a cross-border energy deal in Germany; show me the relationship map for each."
"Draft a follow-up note to the conversation I had yesterday with [Contact] and log it to the matter."
"Show me companies in [sector] that have filed in two new jurisdictions in the last 90 days where we have no relationship."

Every answer is grounded in the firm's LeadLex workspace under the user's existing permissions. No data leaves the firm's perimeter to public AI services. The model interacts with LeadLex through MCP, which is an open standard maintained by Anthropic and increasingly supported across AI clients.

Prerequisites

Before starting:

A user account in your firm's LeadLex workspace with permission to issue MCP credentials (typically a workspace admin, or a user with the "Integrations" permission).
An MCP-aware client. The most common are Claude Desktop and Claude inside Microsoft Teams. Claude Code also works for partners who use it as a working surface.
For Claude Desktop: macOS 13+ or Windows 11, with the latest Claude Desktop version installed.
About twenty minutes.

A developer is not required to complete this guide, but a comfort level with editing one JSON file is helpful.

Step 1 — Generate an MCP credential in LeadLex

In your LeadLex workspace, open Settings → Integrations → MCP. Generate a new credential and choose:

Scope. The set of LeadLex objects the assistant can read and write — typically contacts, accounts, matters, deals, notes. For most BD users, read-everything plus write-notes is the right default. IT can lock down further.
Expiry. Credentials can be set to expire (recommended: 90 days). Rotation is built into the admin panel.
Audience. Bind the credential to a specific user identity. The credential always carries the user's permissions; it cannot exceed them.

Copy the generated token. You will paste it into the MCP client configuration in the next step.

Step 2 — Configure Claude Desktop

Open Claude Desktop's configuration file:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
Windows: %APPDATA%\Claude\claude_desktop_config.json

Add a leadlex entry to the mcpServers block. The shape:

{
  "mcpServers": {
    "leadlex": {
      "command": "npx",
      "args": ["-y", "@leadlex/mcp-server@latest"],
      "env": {
        "LEADLEX_API_TOKEN": "paste-token-from-step-1",
        "LEADLEX_WORKSPACE": "your-workspace-id"
      }
    }
  }
}

Your LeadLex workspace ID is shown under Settings → General in the admin panel. Save the file, then quit and reopen Claude Desktop. The LeadLex tools should appear under the connections panel within a few seconds.

For Claude inside Microsoft Teams, the equivalent configuration is added via the LeadLex Teams admin panel rather than a local file — follow the prompts in the LeadLex setup screen.

Step 3 — Set permissions

The credential issued in Step 1 carries the user's permissions in LeadLex. That means a junior associate's Claude session sees what they would see in the LeadLex web app — no more, no less. There is no separate AI permission layer to configure: identity flows through.

If the firm uses single sign-on, the LeadLex MCP server respects the SSO claims attached to the user's session. IT teams unfamiliar with MCP can think of the integration as an additional client of the LeadLex API, subject to the same access controls as the web product.

Step 4 — First test

Open a fresh conversation in Claude. Type:

"Using LeadLex, list five of my current contacts at [Client], with their most recent activity."

Claude will call the LeadLex MCP server, retrieve the data, and return a clean answer. If you see an error instead, jump to the troubleshooting section below.

A starter prompt set for BD partners

The prompts that produce the most useful answers in the first month:

Brief me. "Give me a one-page brief on [Company] before my call. Include our relationship history, prior matters, and any recent market activity."
Find the warm path. "Who in our firm has the strongest relationship with [Contact] — and what would they say is the best angle?"
Analogue search. "Find the three matters most analogous to a [type] mandate in [jurisdiction]. Pull the lead partner and key learnings."
Follow-up. "Draft a follow-up note to my meeting yesterday with [Contact], grounded in what we discussed and in our standard tone. Log it to the matter."
Quiet opportunity. "Find companies in [sector] that have spiked filings in the last quarter where we have no relationship."
Pitch numbers. "For our pitch to [Client] on Thursday — pull the financials of our three closest prior matters and the satisfaction signal."
Conflicts check. "Are there any conflicts or sensitive matters to flag before reaching out to [Contact]?"

These are not magic. They are the questions a partner already asks an analyst or a BD lead in slow motion. The MCP integration is what lets them be asked at speed, in the channel the partner is already working in.

Troubleshooting

The LeadLex tools don't appear in Claude. Confirm the JSON config has no trailing commas, then fully quit and reopen Claude Desktop (not just close the window). Check that the npx command can run in your shell.

"Permission denied". The token may not have the scope the prompt is asking for. Open Settings → Integrations → MCP in LeadLex, check the credential's scopes, and reissue if needed.

"No data returned". The user the token is bound to may not have visibility into the requested record. Confirm the user's LeadLex permissions in the web app.

Slow responses. MCP servers run locally and pass data through Claude. For very large queries — pulling a year of matter activity, for example — break the request into smaller asks.

Token rotation. Credentials older than the configured expiry stop working silently from the user's point of view. Set a calendar reminder to rotate every 90 days, or have IT do it on a schedule.

Where this leaves the partner

The integration is the technical part. The shift it produces is editorial. The partner stops asking "where is that information" and starts asking the question they actually wanted to ask. The system finds the information; the partner gets the answer.

That is the point of MCP, and it is the point of the AI-native CRM as a category. The partner does the lawyering. The infrastructure does the rest.