This is a testing framework (mcp-jest) for MCP servers, not itself an MCP server. The 17 'tools' listed are actually test definitions spread across example servers (e2e/test-server.js, examples/demo-server.js, tests/filter-test-server.js) used to validate the framework. The source code shows basic tool definitions with minimal descriptions and inconsistent schemas. Many tools lack detailed parameter descriptions, and the framework does not enforce schema quality on the servers it tests. As a framework, mcp-jest should document how to write high-quality tool definitions, but the examples provided are mediocre. The package.json indicates this is a test utility (type: 'module', main: dist/index.js, bin: mcp-jest CLI), not a production MCP server itself.

• Add comprehensive descriptions (50-200 chars) to every tool in every test server. Document WHAT the tool does, WHEN to call it, and what it returns. Use tools like calculate, getUser as reference.
• Consolidate duplicate tools (calculate, echo, add, search) into single canonical implementations across test servers. Use unique tool names for each test scenario.
• Document all parameters, including type, constraints (min/max/enum/pattern), and examples. For example: searchAdvanced.filters should be 'Optional object with keys: status (enum: active|archived), created_after (ISO8601 date), limit (1-100)'.
• Add output schema documentation. For example: getUser returns '{user_id: string, name: string, email: string, created_at: ISO8601}' or getForecast returns '{days: [{date: string, high: number, low: number, condition: string}]}'.
• Implement error handling guidance in descriptions and tool implementations. Example for updateUser: 'Returns error if user_id not found. Returns partial success if some fields fail validation. Retryable on 5xx; user-fixable on 400 (invalid field).'
• Add tool annotations to schema definitions. Mark sendEmail and updateUser with destructiveHint: true; mark all READ tools with readOnlyHint: true. Implement idempotentHint where applicable.
• Add constraints to parameter schemas. Example: getForecast.days should have {type: 'number', minimum: 1, maximum: 365}. searchAdvanced.filters should have a nested schema defining allowed keys.
• Consider batch variants for tools called in loops. For example, add support for addLabels(ticket_ids: [], labels: []) instead of requiring N separate add_label calls.