Security and access controls for AI assistants

What is this page about: How Light controls what a connected AI assistant such as Claude can see and do. It covers how access follows the connected user's role, which actions stay in the Light app, how to set up a dedicated integration user, how personal data is handled, what Light records, and how to cut off access. It's written for security and IT teams reviewing the connection.

# On this page

• How the connection works
• What the assistant can access
• What the assistant can and can't do
• Limit access with a dedicated integration user
• Personal data
• How changes run
• What Light records
• Cut off or adjust access
• Sign-in and tokens
• Rate limits
• Checklist for a security review
• Frequently asked questions
• Related articles

# How the connection works

An AI assistant connects to Light through Light's MCP server at https://api.light.inc/mcp. The assistant runs wherever your AI client runs, so for claude.ai and Claude Desktop that's Anthropic's servers.

Each time the assistant needs Light, it sends a request naming the tool and the details it's using, such as an invoice number. Light checks the request against the connected user's role, runs the tool and sends back the result. Your conversation stays with your AI client.

For setup steps, see Connect your AI assistant to Light.

# What the assistant can access

The assistant acts as the Light user who connected it. It can do everything the Light Command Interface (LCI) can do, scoped to that user's role.

• Tool list: Light shows the assistant only the tools the user's role allows.
• Every request: Light checks the user's role again each time a tool runs.
• Entities: A role applies across every entity in the company.

If you connect with your own login as a Company Admin, the assistant gets the same wide access you have. For a narrower connection, use a dedicated integration user.

# What the assistant can and can't do

Within the connected user's role, the assistant can:

• Look up records, transactions and reports
• Approve bills, purchase requests, credit notes, vendors and cards, when the connected user is the assigned approver
• Create and post journal entries, and post card transactions and customer credits
• Mark a customer invoice as paid, which records the payment without moving money

These actions stay in the Light app, for a person to do:

• Paying bills, starting payments and approving payment batches
• Adding or editing a vendor's bank details
• Inviting, deactivating or deleting users
• Changing user roles and company settings

# Limit access with a dedicated integration user

Create a separate Light user for the assistant and give it only the role its work needs. Then connect the assistant while signed in as that user.

Use a role that can make changes only when the assistant needs to change data in that area. To add the user and set its role, see User Roles and Permissions Overview.

# Personal data

• Bank account numbers: On bank account details, the assistant gets the IBAN, account number or bankgiro masked to its last digits. This applies to every role.
• Reimbursements: The assistant gets yes or no flags for an employee's bank details, never the numbers. It does get the bank's name, city and address.
• Reimbursement profiles: The assistant sees only the connected user's own reimbursement profile.
• Home addresses: The assistant's tools return no employee home addresses.
• Other personal data: Names and other details on records follow the user's role, the same as in the Light app. To keep the assistant away from expenses and reimbursements, give the integration user a role that doesn't cover them.

# How changes run

Every connection can view and change data within the user's role. To keep a connection to viewing only, connect it as a user with a view-only role such as Report viewer or Auditor.

Light labels each tool as read or write and tells the assistant to check with you before it makes a change. Over an external connection such as Claude, a change runs as soon as the assistant calls the tool, so asking is up to the assistant. In Light's own web, mobile, Slack and Teams apps, Light also waits for you to confirm each change.

# What Light records

• Activity history: Changes made through an AI assistant appear in each record's activity history under the connected user, the same way as changes made in the app. With a dedicated integration user, the assistant's changes are easy to tell apart.
• Server logs: Light logs each request in its internal server logs, with the tool, the details the assistant sent, the company and the user.
• Results: Light sends results back to the assistant without storing them.

# Cut off or adjust access

• Revoke a token: The user who created a token can revoke it in Settings → Profile → MCP tokens. It stops working straight away, and the next request gets a 401 error.
• Deactivate the user: A Company Admin can end a user's access, including through an assistant, by deactivating that user.
• Change the role: A Company Admin can narrow what a connection can do by changing the user's role. Light checks the role on every request.
• Remove the connector: For claude.ai and Claude Desktop connectors, remove Light from Claude's connector settings. On Claude Team and Enterprise plans, an Owner controls the connector from Organization settings → Connectors.

# Sign-in and tokens

• Connector sign-in: claude.ai and Claude Desktop connect through a Light sign-in, so no token is shared.
• MCP tokens: Other clients use a token that starts with lmcp_. Light shows it once and stores only a one-way hash.
• Expiry: A new token's expiration date is set to 90 days from creation. The user can change it or clear it.
• Limit: Each user can have up to 20 active tokens.
• Visibility: Each user manages their own tokens.

# Rate limits

Each user can make up to 300 requests a minute. Each company has a daily allowance of 110,000 requests by default. Over a limit, the assistant gets error -32000 with a hint about when to try again.

# Checklist for a security review

1. Create a dedicated Light user for the assistant.
2. Give it the narrowest role that covers the work, such as Report viewer or Auditor.
3. Connect the assistant while signed in as that user.
4. Set a token expiration date that fits your policy.
5. Check the user's activity history to review changes the assistant makes.
6. To end access, revoke the token or deactivate the user.

# Frequently asked questions

Can the assistant do more than the connected user?

The assistant has exactly the connected user's role and permissions. Light checks them on every request.

Can the assistant pay bills or move money?

Paying bills and starting payments stay in the Light app. Marking a customer invoice as paid records the payment without moving money.

Can I give the assistant read-only access?

Connect it as a user with a view-only role, such as Report viewer or Auditor.

Can I keep employee bank details out of the assistant's reach?

Reimbursement bank numbers never reach the assistant, and other bank account numbers arrive masked. To keep expenses and reimbursements out entirely, use an integration user whose role doesn't cover them.

Can I limit the assistant to one entity?

A role applies to every entity in the company, so the assistant reaches the same entities as the connected user.

What stops the assistant from making a change I didn't ask for?

The connected user's role sets the limit. Light tells the assistant to check with you before each change, and a view-only role keeps the connection to viewing. Every change shows in activity history under the connected user.

Who can stop the connection?

The user can revoke their token, and a Company Admin can deactivate the user or change their role.

# Related articles

• Connect your AI assistant to Light
• User Roles and Permissions Overview
• Light Command Interface (LCI)
• How Light Uses AI
• API Access and Custom Integrations

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