Built-in tools
Use these built-in tools to give your agents access to email, calendars, chat, project management, code hosting, spreadsheets/BI, search, social, and general web utilities.Google, Slack, Linear, GitHub, and LinkedIn use OAuth. Exa, Tavily, Pylon, and Twitter/X use workspace secrets (API keys).
Gmail
Read and send email
- Read emails (optionally include body, filter with search)
- Send email or reply to an existing message
- Create draft emails
- Mark messages as read
- Get a conversation thread
- Apply or create labels
- List mailbox labels
Google Calendar
Manage events
- List events for a date
- Get event details
- Create new events
Google Sheets
Spreadsheets
- Create spreadsheets
- Read ranges
BigQuery
Analytics
- Execute SQL queries
Slack
Send and read messages
- Send a direct message to a user
- Post a message to a channel
- Reply in a thread
- Read channel history
- Read thread messages
Post to profile
- Publish a post with optional image or link
Twitter/X
- Read a tweet by ID
- Read recent posts from a list
GitHub
PRs, issues, and content
- List pull requests
- Get pull request details
- Create issues and pull requests
- Comment on issues and pull requests
- Read repository files and list directories
Linear
Manage issues and teams
- List teams and team members
- List issues with filters
- Get issue details
- Create, update, or delete issues
Pylon
Issue management
- List issues
- Get issue details
- Update issues
Search
- Exa web search (optionally fetch page contents)
- Exa LinkedIn profile search
- Tavily web search
Web utilities
- Read webpage text content
- Extract image URLs and metadata
- Notify user (for confirmations/updates)
Remote MCP server tools
Agent Builder can discover and use tools from remote Model Context Protocol (MCP) servers. This lets you connect to external MCP servers and use their tools in your agents.How it works
- Agent Builder discovers tools from remote MCP servers via the standard MCP protocol.
- Headers configured in your workspace are automatically attached when fetching tools or calling them. Headers can be used for authentication.
- Tools from remote servers are available alongside built-in tools in Agent Builder.
Configuration
Configure remote MCP servers in your LangSmith workspace:- Navigate to your workspace settings in the LangSmith UI.
- Add your MCP server URL and any required headers (for example,
Authorization: Bearer {{MCP_TOKEN}}). - Agent Builder automatically discovers tools from the server and applies the configured headers when calling tools.
Use workspace secret placeholders like
{{MCP_TOKEN}} in headers. The platform resolves these from your workspace secrets at runtime.