# Ririnto Sinon MCP Integration > MCP Integration - Skill: `tomevault-io/ririnto-sinon-mcp-integration` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/ririnto-sinon-mcp-integration` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/ririnto-sinon-mcp-integration/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/ririnto-sinon-mcp-integration --- # MCP Integration Configure Model Context Protocol servers to expose external service tools within Claude Code plugins. ## Goal Add MCP server definitions to a plugin so external services become available as tool calls within commands and agents. ## Scope This skill owns: - `.mcp.json` at plugin root (dedicated configuration) - `mcpServers` field in `plugin.json` (inline configuration) - Environment variable expansion and token handling - MCP tool naming and allowed-tools scoping - Security rules for credentials and transport ## Operating rules 1. MUST use `${CLAUDE_PLUGIN_ROOT}` for all bundled paths—never hardcoded absolute paths. 2. MUST use HTTPS for remote servers, WSS for WebSocket connections. 3. MUST NOT hardcode credentials. - Use environment variables or OAuth flows. 4. MUST NOT use wildcards in `allowed-tools`—pre-allow only specific tool names. 5. When the manifest declares `"mcpServers": "./.mcp.json"`, plugin-root `.mcp.json` MUST exist. - When plugin-root `.mcp.json` exists, the manifest SHOULD declare `"mcpServers": "./.mcp.json"`. 6. MAY use `.mcp.json` (recommended for multi-server plugins) or `mcpServers` in `plugin.json` (for single-server plugins). 7. SHOULD test MCP connectivity locally with `/mcp` before publishing. ## Configuration Methods ### Dedicated .mcp.json (Recommended for Multiple Servers) ```jsonc { "github": { "type": "sse", "url": "https://mcp.github.com/sse" }, "database": { "command": "${CLAUDE_PLUGIN_ROOT}/servers/db-server", "env": { "DB_URL": "${DATABASE_URL}" } } } ``` ### Inline mcpServers in plugin.json (For Single-Server Plugins) ```jsonc { "$schema": "https://anthropic.com/claude-code/plugin.schema.json", "name": "my-plugin", "author": { "name": "you" }, "mcpServers": { "api": { "type": "http", "url": "https://api.example.com/mcp", "headers": { "Authorization": "Bearer ${API_TOKEN}" } } } } ``` ## Transport Types - `stdio` — Local process (custom servers). - Use `command` + `args` + `env`. - `SSE` — Hosted OAuth (GitHub, Asana, etc.). - Use `type: "sse"` + `url`. - `HTTP` — REST + token (custom APIs). - Use `type: "http"` + HTTPS URL + bearer token in `headers`. - `WebSocket` — Real-time bidirectional (streaming). - Use `type: "ws"` + WSS URL + auth headers. See `references/transport-types.md` for lifecycle details, failure modes, selection decision tree, and performance characteristics. ### WebSocket (BROKEN - Uses Plaintext, Exposes Credentials) > [!CAUTION] > > This example uses unencrypted plaintext transport. > Use `wss://` instead of `ws://` to encrypt credentials and data. ```jsonc { "realtime": { "type": "ws", "url": "ws://mcp.example.com/ws", "headers": { "Authorization": "Bearer ${TOKEN}" } } } ``` ## Environment variable expansion All fields support `${VAR_NAME}` substitution from the user's environment. Use `${CLAUDE_PLUGIN_ROOT}` for portable bundled paths: ```json { "command": "${CLAUDE_PLUGIN_ROOT}/servers/my-server", "env": { "API_KEY": "${MY_API_KEY}", "LOG_FILE": "${CLAUDE_PLUGIN_ROOT}/logs/mcp.log" } } ``` ## MCP tool naming and allowed-tools MCP tools are prefixed: `mcp__plugin_{{plugin-name}}_{{server-name}}__{{tool-name}}` Pre-allow specific tools in command frontmatter: ```markdown --- allowed-tools: - mcp__plugin_github_github__search_repositories - mcp__plugin_github_github__create_issue --- ``` ### Broken (Wildcard Too Permissive) ```markdown --- allowed-tools: - mcp__plugin_github_github__* --- ``` ### Correct (Specific Tools Only) ```markdown --- allowed-tools: - mcp__plugin_github_github__search_repositories - mcp__plugin_github_github__create_issue --- ``` ## Multi-server example Plugin with multiple MCP servers in `.mcp.json`: ```jsonc { "github": { "type": "sse", "url": "https://mcp.github.com/sse" }, "slack": { "type": "sse", "url": "https://mcp.slack.com/sse" }, "dev-db": { "command": "python3", "args": ["-m", "postgres_mcp"], "env": { "DATABASE_URL": "${POSTGRES_URL}" } } } ``` ## Authentication patterns OAuth (SSE/HTTP): Handled automatically by Claude Code. User authenticates in browser on first use. Token (HTTP/WebSocket): Pass via environment variables in headers: ```json { "type": "http", "headers": { "Authorization": "Bearer ${API_TOKEN}" } } ``` Environment variables (stdio): Pass to server process: ```json { "command": "python", "args": ["-m", "mcp_server"], "env": { "DATABASE_URL": "${DB_URL}", "API_KEY": "${API_KEY}" } } ``` ## Security ### Broken (HTTP Without Encryption, Hardcoded Token) > [!CAUTION] > > This example exposes credentials and uses unencrypted transport. > Use HTTPS and environment variables instead. ```jsonc { "type": "http", "url": "http://api.example.com/mcp", "headers": { "Authorization": "Bearer secret_token_12345" } } ``` ### Correct (HTTPS, Environment Variable, No Wildcards) ```jsonc { "type": "http", "url": "https://api.example.com/mcp", "headers": { "Authorization": "Bearer ${API_TOKEN}" } } ``` Document required environment variables in plugin README. ## First safe commands Validate JSON syntax: ```sh python3 -m json.tool .mcp.json ``` List active MCP servers in Claude Code: ```text /mcp ``` Test a specific MCP server's connectivity and tools after plugin restart (required after config changes): ```text /mcp test ``` Distinction: `/mcp` displays all configured servers and their tools. `/mcp test {{server}}` establishes a live connection to verify the server responds correctly and tool definitions are accessible. ## Testing checklist - [ ] Configuration JSON is syntactically valid - [ ] All file paths use `${CLAUDE_PLUGIN_ROOT}` - [ ] Remote URLs use HTTPS/WSS, not HTTP/WS - [ ] No hardcoded credentials - [ ] Required environment variables documented in README - [ ] `/mcp` command shows servers and tools - [ ] Tool calls succeed from commands - [ ] Error handling for connection failures ## Pitfalls DO: Use `${CLAUDE_PLUGIN_ROOT}` for bundled paths, document required env vars, use HTTPS/WSS, pre-allow specific tools only, test with `/mcp` after config changes. DON'T: Hardcode absolute paths, commit credentials, use HTTP instead of HTTPS, pre-allow all tools with `*`, skip error handling. ## References For detailed patterns and advanced topics, see: - `references/transport-types.md` — Transport-specific lifecycle, failure modes, and OAuth internals. - `references/authentication.md` — OAuth, token rotation, and secret hygiene patterns. - `references/performance.md` — Lazy loading, connection pooling, and MCP latency debugging. --- > Source: [ririnto/sinon](https://github.com/ririnto/sinon) — distributed by [TomeVault](https://tomevault.io).