Chroma MCP Server

Instructions

Implementation Reference

• src/chroma/server.py:411-448 (handler)

  Main execution logic for the read_document tool: extracts document_id, fetches from Chroma collection using collection.get(), handles not found errors, formats content and metadata into TextContent response.

  @retry_operation("read_document")
  async def handle_read_document(arguments: dict) -> list[types.TextContent]:
      """Handle document reading with retry logic"""
      doc_id = arguments.get("document_id")
  
      if not doc_id:
          raise DocumentOperationError("Missing document_id")
  
      logger.info(f"Reading document with ID: {doc_id}")
  
      try:
          result = collection.get(ids=[doc_id])
          
          if not result or not result.get('ids') or len(result['ids']) == 0:
              raise DocumentOperationError(f"Document not found [id={doc_id}]")
  
          logger.info(f"Successfully retrieved document: {doc_id}")
          
          # Format the response
          doc_content = result['documents'][0]
          doc_metadata = result['metadatas'][0] if result.get('metadatas') else {}
          
          response = [
              f"Document ID: {doc_id}",
              f"Content: {doc_content}",
              f"Metadata: {doc_metadata}"
          ]
  
          return [
              types.TextContent(
                  type="text",
                  text="\n".join(response)
              )
          ]
  
      except Exception as e:
          raise DocumentOperationError(str(e))

• src/chroma/server.py:257-267 (schema)

  Input schema definition for read_document tool, exposed via the list_tools() handler. Requires 'document_id' string.

  types.Tool(
      name="read_document",
      description="Retrieve a document from the Chroma vector database by its ID",
      inputSchema={
          "type": "object",
          "properties": {
              "document_id": {"type": "string"}
          },
          "required": ["document_id"]
      }
  ),

• src/chroma/server.py:333-334 (registration)

  Dispatch logic in the @server.call_tool() handler that routes 'read_document' calls to the handle_read_document function.

  elif name == "read_document":
      return await handle_read_document(arguments)

• src/chroma/server.py:149-155 (schema)

  Internal command_options schema for read_document tool validation, identical to the exposed schema.

  "read_document": {
      "type": "object",
      "properties": {
          "document_id": {"type": "string"}
      },
      "required": ["document_id"]
  },