dust-mcp-server

name	dust-mcp-server
description	Step-by-step guide for creating new internal MCP server integrations in Dust that connect to remote platforms (Jira, HubSpot, Salesforce, etc.). Use when adding a new MCP server, implementing a platform integration, or connecting Dust to a new external service.

MCP Server Runbook: Adding Internal MCP Server Integrations for Remote Platforms

This runbook provides step-by-step instructions for creating new internal MCP server integrations in Dust that connect to remote platforms (e.g., Jira, HubSpot, Salesforce, etc.).

Quick Reference

File Structure

front/lib/api/actions/servers/{provider}/
├── metadata.ts           # Tool metadata and server info using createToolsRecord
├── tools/index.ts        # Tool handlers with exhaustive Record type
├── index.ts              # Server creation and tool registration
├── client.ts             # API client (optional)
└── helpers.ts            # Helper functions (optional)

Registration Files

1. front/lib/actions/mcp_internal_actions/constants.ts - Add server config with metadata: YOUR_SERVER
2. front/lib/actions/mcp_internal_actions/servers/index.ts - Import and register in switch statement

OAuth Requirements (if the platform requires OAuth)

• OAuth provider must already exist in front/lib/api/oauth/providers/{provider}.ts
• OAuth core implementation must exist in core/src/oauth/providers/{provider}.rs
• OAuth scopes must be configured for the required API access
• Server's authorization field must reference the OAuth provider

Common Gotchas

• Do not forget to add the server to AVAILABLE_INTERNAL_MCP_SERVER_NAMES array
• Server IDs must be stable and unique; never change them once deployed
• Tool stakes must be configured appropriately (never_ask, low, medium, high)
• Always implement proper error handling with Result types
• Handle OAuth token refresh automatically through the withAuth pattern

Prerequisites

OAuth Configuration (if required)

If the remote platform requires OAuth authentication:

1. Check whether an OAuth provider exists in core/src/oauth/providers/ as {provider}.rs
2. Check whether a front OAuth provider exists in front/lib/api/oauth/providers/{provider}.ts

If the OAuth provider does not exist, implement it first in core and front:

• create core/src/oauth/providers/{provider}.rs
• implement the OAuth flow: authorization URL, token exchange, refresh
• register the provider in core/src/oauth/providers/mod.rs
• create front/lib/api/oauth/providers/{provider}.ts for the front-end OAuth setup

See existing providers like hubspot.rs or jira.rs for reference implementations.

Research Phase

Before starting implementation, research the platform API:

1. API Documentation

• find the official API documentation
• identify REST endpoints vs GraphQL vs SDK usage
• note rate limits and pagination requirements

2. Authentication Method

• OAuth 2.0, preferred for user-facing integrations
• API key / bearer token, simpler but less secure
• required OAuth scopes

3. Available Operations

Document the operations you want to expose:

• read operations: list, get, search
• write operations: create, update, delete
• special operations: transitions, associations, etc.

Step-by-Step Implementation

1. Create metadata.ts

Create front/lib/api/actions/servers/{provider}/metadata.ts:

import type { JSONSchema7 as JSONSchema } from "json-schema";
import { z } from "zod";
import { zodToJsonSchema } from "zod-to-json-schema";

import type { ServerMetadata } from "@app/lib/actions/mcp_internal_actions/tool_definition";
import { createToolsRecord } from "@app/lib/actions/mcp_internal_actions/tool_definition";

export const YOUR_PROVIDER_TOOLS_METADATA = createToolsRecord({
  list_items: {
    description: "List all items accessible to the user.",
    schema: {
      pageToken: z.string().optional().describe("Page token for pagination."),
      maxResults: z.number().optional().describe("Maximum results to return."),
    },
    stake: "never_ask",
    displayLabels: {
      running: "Listing Items",
      done: "List items",
    },
  },
  get_item: {
    description: "Get a single item by ID.",
    schema: {
      itemId: z.string().describe("The ID of the item to retrieve."),
    },
    stake: "never_ask",
    displayLabels: {
      running: "Retrieving item",
      done: "Retrieve item",
    },
  },
  create_item: {
    description: "Create a new item.",
    schema: {
      name: z.string().describe("Name of the item."),
      description: z.string().optional().describe("Description of the item."),
    },
    stake: "low",
    displayLabels: {
      running: "Creating item",
      done: "Create item",
    },
  },
});

export const YOUR_PROVIDER_SERVER = {
  serverInfo: {
    name: "your_provider",
    version: "1.0.0",
    description: "Short description of what this integration does.",
    authorization: {
      provider: "your_provider",
      supported_use_cases: ["personal_actions", "platform_actions"],
    },
    icon: "YourProviderLogo",
    documentationUrl: "https://docs.dust.tt/docs/your-provider",
    instructions: null,
  },
  tools: Object.values(YOUR_PROVIDER_TOOLS_METADATA).map((t) => ({
    name: t.name,
    description: t.description,
    inputSchema: zodToJsonSchema(z.object(t.schema)) as JSONSchema,
    displayLabels: t.displayLabels,
  })),
  tools_stakes: Object.fromEntries(
    Object.values(YOUR_PROVIDER_TOOLS_METADATA).map((t) => [t.name, t.stake])
  ),
} as const satisfies ServerMetadata;

Key points:

• createToolsRecord automatically adds the name property from the object key
• tool keys become the source of truth
• stake values map to review/approval expectations

2. Create tools/index.ts

Create front/lib/api/actions/servers/{provider}/tools/index.ts:

import { MCPError } from "@app/lib/actions/mcp_errors";
import type { ToolHandlers } from "@app/lib/actions/mcp_internal_actions/tool_definition";
import { buildTools } from "@app/lib/actions/mcp_internal_actions/tool_definition";
import { YOUR_PROVIDER_TOOLS_METADATA } from "@app/lib/api/actions/servers/your_provider/metadata";
import { Err, Ok } from "@app/types/shared/result";

const handlers: ToolHandlers<typeof YOUR_PROVIDER_TOOLS_METADATA> = {
  list_items: async ({ pageToken, maxResults }, { authInfo }) => {
    const token = authInfo?.token;
    if (!token) {
      return new Err(new MCPError("No access token provided"));
    }

    try {
      const items = [];

      return new Ok([
        { type: "text" as const, text: `Found ${items.length} items` },
        { type: "text" as const, text: JSON.stringify({ items }, null, 2) },
      ]);
    } catch (e) {
      return new Err(new MCPError("Failed to list items"));
    }
  },

  get_item: async ({ itemId }, { authInfo }) => {
    const token = authInfo?.token;
    if (!token) {
      return new Err(new MCPError("No access token provided"));
    }

    try {
      const item = {};

      return new Ok([
        { type: "text" as const, text: `Retrieved item ${itemId}` },
        { type: "text" as const, text: JSON.stringify(item, null, 2) },
      ]);
    } catch (e) {
      return new Err(new MCPError("Failed to get item"));
    }
  },

  create_item: async ({ name, description }, { authInfo }) => {
    const token = authInfo?.token;
    if (!token) {
      return new Err(new MCPError("No access token provided"));
    }

    try {
      const item = {};

      return new Ok([
        { type: "text" as const, text: `Created item "${name}"` },
        { type: "text" as const, text: JSON.stringify(item, null, 2) },
      ]);
    } catch (e) {
      return new Err(new MCPError("Failed to create item"));
    }
  },
};

export const TOOLS = buildTools(YOUR_PROVIDER_TOOLS_METADATA, handlers);

Key points:

• ToolHandlers<T> enforces exhaustive implementation
• buildTools combines metadata and handlers into ToolDefinition[]
• each handler receives typed params inferred from the schema
• access the OAuth token via extra.authInfo?.token

3. Create index.ts

Create front/lib/api/actions/servers/{provider}/index.ts:

import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";

import { makeInternalMCPServer } from "@app/lib/actions/mcp_internal_actions/utils";
import { registerTool } from "@app/lib/actions/mcp_internal_actions/wrappers";
import type { AgentLoopContextType } from "@app/lib/actions/types";
import { TOOLS } from "@app/lib/api/actions/servers/your_provider/tools";
import type { Authenticator } from "@app/lib/auth";

function createServer(
  auth: Authenticator,
  agentLoopContext?: AgentLoopContextType
): McpServer {
  const server = makeInternalMCPServer("your_provider");

  for (const tool of TOOLS) {
    registerTool(auth, agentLoopContext, server, tool, {
      monitoringName: "your_provider",
    });
  }

  return server;
}

export default createServer;

4. Register in constants.ts

Edit front/lib/actions/mcp_internal_actions/constants.ts:

• import YOUR_PROVIDER_SERVER
• add the server name to AVAILABLE_INTERNAL_MCP_SERVER_NAMES
• add the config entry to INTERNAL_MCP_SERVERS

Example:

your_provider: {
  id: 99,
  availability: "manual",
  allowMultipleInstances: true,
  isRestricted: undefined,
  isPreview: false,
  tools_arguments_requiring_approval: undefined,
  tools_retry_policies: undefined,
  timeoutMs: undefined,
  metadata: YOUR_PROVIDER_SERVER,
},

Important properties:

• id: unique stable ID, never change after deployment
• availability: manual, auto, or auto_hidden_builder
• allowMultipleInstances: true for OAuth-based integrations
• isRestricted: feature-flag or plan gating function, if needed
• isPreview: true for beta or preview integrations

5. Register in servers/index.ts

Edit front/lib/actions/mcp_internal_actions/servers/index.ts:

case "your_provider":
  return yourProviderServer(auth, agentLoopContext);

Optional: client.ts and helpers.ts

Use extra files when the integration grows beyond a few simple calls.

client.ts

Create a client when you need multiple API endpoints, response validation, auth header management, or retry logic.

helpers.ts

Create helpers for:

• withAuth wrappers
• response rendering
• shared data transformations

Example withAuth pattern:

import { MCPError } from "@app/lib/actions/mcp_errors";
import type {
  ToolHandlerExtra,
  ToolHandlerResult,
} from "@app/lib/actions/mcp_internal_actions/tool_definition";
import { Err } from "@app/types/shared/result";

export async function withAuth<T>(
  { authInfo }: ToolHandlerExtra,
  action: (token: string) => Promise<ToolHandlerResult>
): Promise<ToolHandlerResult> {
  const token = authInfo?.token;
  if (!token) {
    return new Err(new MCPError("No access token provided"));
  }

  try {
    return await action(token);
  } catch (e) {
    return new Err(new MCPError("Operation failed"));
  }
}

Use client.ts / helpers.ts based on complexity:

• no external API: keep everything in tools/index.ts
• 1-2 simple API calls: inline, maybe add helpers.ts
• several API endpoints: create client.ts
• complex response formatting: add dedicated rendering helpers

Alternative: function-based tools

If handlers need access to Authenticator directly, create tools through a function instead of a constant.

See front/lib/api/actions/servers/github/tools/index.ts for a full example.

Icon

Use an existing similar icon temporarily, then request the final icon from design/Sparkle and update the icon field once available.

Feature Flags and Restrictions

Gate preview or limited-access servers through isRestricted in the server config, using feature flags or plan checks as needed.

Best Practices

1. Render responses for token efficiency

Always convert API responses into focused, markdown-formatted output. Avoid returning raw JSON.stringify(apiResponse) with everything the upstream API sent.

Do:

• keep only the fields the model needs
• start with a short summary
• format structured results consistently

Do not:

• return full raw API responses
• include pagination metadata or rate-limit details unless needed
• duplicate the same data in multiple formats

2. Translate errors into actionable messages

Wrap failures in meaningful MCPErrors rather than exposing raw upstream errors.

3. Choose tool stakes carefully

• never_ask: read-only operations
• low: low-impact writes
• medium: important writes
• high: destructive or high-impact actions

4. Add .describe() to schema fields

Schema descriptions help the model supply the right parameters.

5. Validate external API responses with Zod

Validate every external response to catch API drift and unexpected payloads early.

Validation Checklist

Before marking implementation complete:

• metadata.ts exists and uses createToolsRecord
• tools/index.ts exists and uses ToolHandlers<typeof METADATA>
• index.ts default-exports the server factory
• the server is in AVAILABLE_INTERNAL_MCP_SERVER_NAMES
• the server config is in INTERNAL_MCP_SERVERS
• the server is registered in servers/index.ts
• response rendering is implemented
• a temporary icon is set
• feature gating is configured if needed
• npx tsgo --noEmit passes
• npm run format:changed passes from the repo root
• manual testing is complete

Troubleshooting

Server not appearing in the builder

• check availability
• check isRestricted
• verify the server name is in AVAILABLE_INTERNAL_MCP_SERVER_NAMES

OAuth connection failing

• verify the provider exists in core and front
• check client ID / secret env vars
• verify redirect URIs and scopes

Tools not working

• verify the tool is registered
• verify tools_stakes contains the tool names
• test the API helper functions directly
• confirm authInfo.token is propagated

Type errors

• ensure the server name was added to AVAILABLE_INTERNAL_MCP_SERVER_NAMES
• run npx tsgo --noEmit
• if handler typing fails, re-check the metadata/handler mapping

Reference Implementations

• front/lib/api/actions/servers/github/
• front/lib/api/actions/servers/snowflake/
• front/lib/api/actions/servers/google_calendar/
• front/lib/api/actions/servers/agent_sidekick_context/
• front/lib/api/actions/servers/agent_sidekick_agent_state/

Additional Resources

• MCP SDK documentation: https://modelcontextprotocol.io/
• existing server implementations in front/lib/api/actions/servers/
• legacy implementations in front/lib/actions/mcp_internal_actions/servers/
• OAuth providers in core/src/oauth/providers/