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cliffhall 1b8f376b90 Demonstrate registration of tools conditioned upon client capability support. Also, obviated need for clientConnected callback to pass sessionId because we defer initial fetching of roots happens when you run the get-roots-list tool.

* In how-it-works.md,
  - added a section on conditional tool registration

* In server/index.ts
  - import registerConditionalTools
  - in an oninitialized handler for the server, call registerConditionalTools
  - removed clientConnected from ServerFactoryResponse and all mentions in docs

* In tools/index.ts
  - export a registerConditionalTools function
  - refactor/move calls to registerGetRootsListTool, registerTriggerElicitationRequestTool, and registerTriggerSamplingRequestTool out of registerTools and into registerConditionalTools

* In server/roots.ts
  - only act if client supports roots
  - remove setInterval from call to requestRoots. It isn't happening during the initialze handshake anymore, so it doesn't interfere with that process if called immediaately

* In get-roots-list.ts, trigger-elicitation-request.ts, and trigger-sampling-request.ts,
  - only register tool if client supports capability

* Throughout the rest of the files, removing all references to `clientConnected`

2025-12-15 17:51:30 -05:00

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MCP "Everything" Server - Development Guidelines

Build, Test & Run Commands

Build: npm run build - Compiles TypeScript to JavaScript
Watch mode: npm run watch - Watches for changes and rebuilds automatically
Run STDIO server: npm run start:stdio - Starts the MCP server using stdio transport
Run SSE server: npm run start:sse - Starts the MCP server with SSE transport
Run StreamableHttp server: npm run start:stremableHttp - Starts the MCP server with StreamableHttp transport
Prepare release: npm run prepare - Builds the project for publishing

Code Style Guidelines

Use ES modules with .js extension in import paths
Strictly type all functions and variables with TypeScript
Follow zod schema patterns for tool input validation
Prefer async/await over callbacks and Promise chains
Place all imports at top of file, grouped by external then internal
Use descriptive variable names that clearly indicate purpose
Implement proper cleanup for timers and resources in server shutdown
Handle errors with try/catch blocks and provide clear error messages
Use consistent indentation (2 spaces) and trailing commas in multi-line objects
Match existing code style, import order, and module layout in the respective folder.
Use camelCase for variables/functions,
Use PascalCase for types/classes,
Use UPPER_CASE for constants
Use kebab-case for file names and registered tools, prompts, and resources.
Use verbs for tool names, e.g., get-annotated-message instead of annotated-message

Extending the Server

The Everything Server is designed to be extended at well-defined points. See Extension Points and Project Structure. The server factory is src/everything/server/index.ts and registers all features during startup as well as handling post-connection setup.

High-level

Tools live under src/everything/tools/ and are registered via registerTools(server).
Resources live under src/everything/resources/ and are registered via registerResources(server).
Prompts live under src/everything/prompts/ and are registered via registerPrompts(server).
Subscriptions and simulated update routines are under src/everything/resources/subscriptions.ts.
Logging helpers are under src/everything/server/logging.ts.
Transport managers are under src/everything/transports/.

When adding a new feature

Follow the existing file/module pattern in its folder (naming, exports, and registration function).
Export a registerX(server) function that registers new items with the MCP SDK in the same style as existing ones.
Wire your new module into the central index (e.g., update tools/index.ts, resources/index.ts, or prompts/index.ts).
Ensure schemas (for tools) are accurate JSON Schema and include helpful descriptions and examples. server/index.ts and usages in logging.ts and subscriptions.ts.
Keep the docs in src/everything/docs/ up to date if you add or modify noteworthy features.

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