What is the Harvey MCP Server?
The Harvey MCP Server exposes some of Harvey’s core features — legal Q&A, Vault document analysis, and research knowledge sources as MCP tools. It is designed to work with MCP-compatible clients such as Claude Web or Desktop.What can you do with the Harvey MCP Server?
- Ask general legal questions — Get answers from Harvey’s broad legal knowledge without referencing specific documents.
- Analyze Vault documents — Ask questions about documents in your Vault projects with source citations.
- Discover resources — List your Vault projects and available knowledge sources to find the right context for your questions.
- Research with knowledge sources — Query specialized legal research databases like UK tax law.
Setup guides
Prerequisites
- A Harvey account
- An AI assistant like Claude Web or Desktop. Harvey MCP only works with Anthropic’s AI assistants currently.
Claude Web
- Open and sign in to Claude.
- Go to Settings.
- Go to Connectors, search for Harvey.
- Connect, authenticate, and make sure the Harvey connector is toggled on when chatting.
Claude Desktop
- Open Claude Desktop and sign in.
- Go to Settings.
- Go to Connectors, search for Harvey.
- Connect and authenticate with your Harvey account.
- Once connected, Harvey tools will appear in your conversations.
Available tools
| Tool | Description | Example prompts |
|---|---|---|
ask_harvey | Ask a general legal question using Harvey’s broad legal knowledge | ”What are the elements of a breach of contract claim?” |
ask_with_knowledge_source | Ask a question using a specific research knowledge source | ”What is the HMRC guidance on capital gains for non-residents?” |
list_knowledge_sources | List all available research knowledge sources | ”What research databases can I search?” |
list_vault_projects | List all Vault projects accessible to the authenticated user | ”What Vault projects do I have access to?” |
ask_about_vault | Ask a question about documents in a specific Vault project | ”Summarize the indemnification clauses in this project” |
Troubleshooting
Hosted MCP server is not enabled for this user
Hosted MCP server is not enabled for this user
Check with your Harvey admin or representative to ensure you’re enrolled in this feature.
You do not have permission to use this tool
You do not have permission to use this tool
Your Harvey account lacks the required permission for the specific tool you’re trying to use. For example,
ask_about_vault requires the VAULT permission. Contact your Harvey workspace administrator to check your permissions.Invalid vault_project_id format
Invalid vault_project_id format
The
vault_project_id parameter must be a valid UUID. Use list_vault_projects first to get valid project IDs.Unknown knowledge source type
Unknown knowledge source type
The
knowledge_source_type value doesn’t match any available knowledge source. Use list_knowledge_sources to see valid types for your account.Authentication fails or token is rejected
Authentication fails or token is rejected
- Verify your Harvey account is active and you have access to the MCP feature.
- Try re-authenticating by removing and re-adding the MCP server in your client.
Tools not appearing in my MCP client
Tools not appearing in my MCP client
- Check that your MCP client supports Streamable HTTP transport (not just SSE or stdio).
- Re-authenticate if the connection was previously established.
FAQ
Can multiple users connect to the same MCP server?
Can multiple users connect to the same MCP server?
Yes. Each user authenticates individually through the browser OAuth flow. The server resolves each request to the authenticated user and enforces their specific permissions and feature gates.
What data does the MCP server have access to?
What data does the MCP server have access to?
The MCP server can only access data that the authenticated user has permission to view in Harvey. Vault project queries are scoped to projects the user can access, and knowledge source queries are limited to sources enabled for the user’s account.
Does this support conversation history?
Does this support conversation history?
Each tool call is stateless — the server does not maintain conversation history between requests. To build multi-turn workflows, your MCP client should manage context across tool calls.