# How to integrate Dictionary api MCP with Mastra AI ```json { "title": "How to integrate Dictionary api MCP with Mastra AI", "toolkit": "Dictionary api", "toolkit_slug": "dictionary_api", "framework": "Mastra AI", "framework_slug": "mastra-ai", "url": "https://composio.dev/toolkits/dictionary_api/framework/mastra-ai", "markdown_url": "https://composio.dev/toolkits/dictionary_api/framework/mastra-ai.md", "updated_at": "2026-05-12T10:08:42.039Z" } ``` ## Introduction This guide walks you through connecting Dictionary api to Mastra AI using the Composio tool router. By the end, you'll have a working Dictionary api agent that can get the definition and synonyms for 'ubiquitous', find the origin and pronunciation of 'serendipity', list antonyms for the word 'ambiguous' through natural language commands. This guide will help you understand how to give your Mastra AI agent real control over a Dictionary api account through Composio's Dictionary api MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved. ## Also integrate Dictionary api with - [OpenAI Agents SDK](https://composio.dev/toolkits/dictionary_api/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/dictionary_api/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/dictionary_api/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/dictionary_api/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/dictionary_api/framework/codex) - [OpenClaw](https://composio.dev/toolkits/dictionary_api/framework/openclaw) - [Hermes](https://composio.dev/toolkits/dictionary_api/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/dictionary_api/framework/cli) - [Google ADK](https://composio.dev/toolkits/dictionary_api/framework/google-adk) - [LangChain](https://composio.dev/toolkits/dictionary_api/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/dictionary_api/framework/ai-sdk) - [LlamaIndex](https://composio.dev/toolkits/dictionary_api/framework/llama-index) - [CrewAI](https://composio.dev/toolkits/dictionary_api/framework/crew-ai) ## TL;DR Here's what you'll learn: - Set up your environment so Mastra, OpenAI, and Composio work together - Create a Tool Router session in Composio that exposes Dictionary api tools - Connect Mastra's MCP client to the Composio generated MCP URL - Fetch Dictionary api tool definitions and attach them as a toolset - Build a Mastra agent that can reason, call tools, and return structured results - Run an interactive CLI where you can chat with your Dictionary api agent ## What is Mastra AI? Mastra AI is a TypeScript framework for building AI agents with tool support. It provides a clean API for creating agents that can use external services through MCP. Key features include: - MCP Client: Built-in support for Model Context Protocol servers - Toolsets: Organize tools into logical groups - Step Callbacks: Monitor and debug agent execution - OpenAI Integration: Works with OpenAI models via @ai-sdk/openai ## What is the Dictionary api MCP server, and what's possible with it? The Dictionary api MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Dictionary api account. It provides structured and secure access to comprehensive dictionary and thesaurus data, so your agent can look up definitions, explore word origins, access pronunciations, and discover synonyms or antonyms on your behalf. - Instant word definition lookup: Ask your agent to fetch clear, detailed definitions for any word you encounter. - Etymology and origin insights: Let the agent retrieve the historical roots and language origin of specific words for deeper understanding. - Audio pronunciation access: Have your agent provide accurate audio pronunciations, helping with proper usage and learning. - Synonyms and antonyms discovery: Quickly find synonyms and antonyms to enrich your vocabulary or refine your writing style. - Comprehensive lexical information: Enable your agent to surface all available meanings, usage examples, and nuanced word senses for precise communication. ## Supported Tools | Tool slug | Name | Description | |---|---|---| | `DICTIONARY_API_GET_WORD_DEFINITION_V2` | Get Word Definition | Retrieve comprehensive dictionary data for a word including definitions, phonetics, etymology, synonyms, and antonyms. Uses the Free Dictionary API (dictionaryapi.dev) - a free, open-source dictionary powered by Wiktionary data. Returns detailed word information including multiple definitions grouped by part of speech, pronunciation audio, example sentences, and related words. Ideal for language learning, writing assistance, and vocabulary exploration. Note: Primarily supports English ('en'). Other languages may have limited coverage. | ## Supported Triggers None listed. ## Creating MCP Server - Stand-alone vs Composio SDK The Dictionary api MCP server is an implementation of the Model Context Protocol that connects your AI agent to Dictionary api. It provides structured and secure access so your agent can perform Dictionary api operations on your behalf through a secure, permission-based interface. With Composio's managed implementation, you don't have to create your own developer app. For production, if you're building an end product, we recommend using your own credentials. The managed server helps you prototype fast and go from 0-1 faster. ## Step-by-step Guide ### 1. Prerequisites Before starting, make sure you have: - Node.js 18 or higher - A Composio account with an active API key - An OpenAI API key - Basic familiarity with TypeScript ### 1. Getting API Keys for OpenAI and Composio OpenAI API Key - Go to the [OpenAI dashboard](https://platform.openai.com/settings/organization/api-keys) and create an API key. - You need credits or a connected billing setup to use the models. - Store the key somewhere safe. Composio API Key - Log in to the [Composio dashboard](https://dashboard.composio.dev?utm_source=toolkits&utm_medium=framework_docs). - Go to Settings and copy your API key. - This key lets your Mastra agent talk to Composio and reach Dictionary api through MCP. ### 2. Install dependencies Install the required packages. What's happening: - @composio/core is the Composio SDK for creating MCP sessions - @mastra/core provides the Agent class - @mastra/mcp is Mastra's MCP client - @ai-sdk/openai is the model wrapper for OpenAI - dotenv loads environment variables from .env ```bash npm install @composio/core @mastra/core @mastra/mcp @ai-sdk/openai dotenv ``` ### 3. Set up environment variables Create a .env file in your project root. What's happening: - COMPOSIO_API_KEY authenticates your requests to Composio - COMPOSIO_USER_ID tells Composio which user this session belongs to - OPENAI_API_KEY lets the Mastra agent call OpenAI models ```bash COMPOSIO_API_KEY=your_composio_api_key_here COMPOSIO_USER_ID=your_user_id_here OPENAI_API_KEY=your_openai_api_key_here ``` ### 4. Import libraries and validate environment What's happening: - dotenv/config auto loads your .env so process.env.* is available - openai gives you a Mastra compatible model wrapper - Agent is the Mastra agent that will call tools and produce answers - MCPClient connects Mastra to your Composio MCP server - Composio is used to create a Tool Router session ```typescript import "dotenv/config"; import { openai } from "@ai-sdk/openai"; import { Agent } from "@mastra/core/agent"; import { MCPClient } from "@mastra/mcp"; import { Composio } from "@composio/core"; import * as readline from "readline"; import type { AiMessageType } from "@mastra/core/agent"; const openaiAPIKey = process.env.OPENAI_API_KEY; const composioAPIKey = process.env.COMPOSIO_API_KEY; const composioUserID = process.env.COMPOSIO_USER_ID; if (!openaiAPIKey) throw new Error("OPENAI_API_KEY is not set"); if (!composioAPIKey) throw new Error("COMPOSIO_API_KEY is not set"); if (!composioUserID) throw new Error("COMPOSIO_USER_ID is not set"); const composio = new Composio({ apiKey: composioAPIKey as string, }); ``` ### 5. Create a Tool Router session for Dictionary api What's happening: - create spins up a short-lived MCP HTTP endpoint for this user - The toolkits array contains "dictionary_api" for Dictionary api access - session.mcp.url is the MCP URL that Mastra's MCPClient will connect to ```typescript async function main() { const session = await composio.create( composioUserID as string, { toolkits: ["dictionary_api"], }, ); const composioMCPUrl = session.mcp.url; console.log("Dictionary api MCP URL:", composioMCPUrl); ``` ### 6. Configure Mastra MCP client and fetch tools What's happening: - MCPClient takes an id for this client and a list of MCP servers - The headers property includes the x-api-key for authentication - getTools fetches the tool definitions exposed by the Dictionary api toolkit ```typescript const mcpClient = new MCPClient({ id: composioUserID as string, servers: { nasdaq: { url: new URL(composioMCPUrl), requestInit: { headers: session.mcp.headers, }, }, }, timeout: 30_000, }); console.log("Fetching MCP tools from Composio..."); const composioTools = await mcpClient.getTools(); console.log("Number of tools:", Object.keys(composioTools).length); ``` ### 7. Create the Mastra agent What's happening: - Agent is the core Mastra agent - name is just an identifier for logging and debugging - instructions guide the agent to use tools instead of only answering in natural language - model uses openai("gpt-5") to configure the underlying LLM ```typescript const agent = new Agent({ name: "dictionary_api-mastra-agent", instructions: "You are an AI agent with Dictionary api tools via Composio.", model: "openai/gpt-5", }); ``` ### 8. Set up interactive chat interface What's happening: - messages keeps the full conversation history in Mastra's expected format - agent.generate runs the agent with conversation history and Dictionary api toolsets - maxSteps limits how many tool calls the agent can take in a single run - onStepFinish is a hook that prints intermediate steps for debugging ```typescript let messages: AiMessageType[] = []; console.log("Chat started! Type 'exit' or 'quit' to end.\n"); const rl = readline.createInterface({ input: process.stdin, output: process.stdout, prompt: "> ", }); rl.prompt(); rl.on("line", async (userInput: string) => { const trimmedInput = userInput.trim(); if (["exit", "quit", "bye"].includes(trimmedInput.toLowerCase())) { console.log("\nGoodbye!"); rl.close(); process.exit(0); } if (!trimmedInput) { rl.prompt(); return; } messages.push({ id: crypto.randomUUID(), role: "user", content: trimmedInput, }); console.log("\nAgent is thinking...\n"); try { const response = await agent.generate(messages, { toolsets: { dictionary_api: composioTools, }, maxSteps: 8, }); const { text } = response; if (text && text.trim().length > 0) { console.log(`Agent: ${text}\n`); messages.push({ id: crypto.randomUUID(), role: "assistant", content: text, }); } } catch (error) { console.error("\nError:", error); } rl.prompt(); }); rl.on("close", async () => { console.log("\nSession ended."); await mcpClient.disconnect(); process.exit(0); }); } main().catch((err) => { console.error("Fatal error:", err); process.exit(1); }); ``` ## Complete Code ```typescript import "dotenv/config"; import { openai } from "@ai-sdk/openai"; import { Agent } from "@mastra/core/agent"; import { MCPClient } from "@mastra/mcp"; import { Composio } from "@composio/core"; import * as readline from "readline"; import type { AiMessageType } from "@mastra/core/agent"; const openaiAPIKey = process.env.OPENAI_API_KEY; const composioAPIKey = process.env.COMPOSIO_API_KEY; const composioUserID = process.env.COMPOSIO_USER_ID; if (!openaiAPIKey) throw new Error("OPENAI_API_KEY is not set"); if (!composioAPIKey) throw new Error("COMPOSIO_API_KEY is not set"); if (!composioUserID) throw new Error("COMPOSIO_USER_ID is not set"); const composio = new Composio({ apiKey: composioAPIKey as string }); async function main() { const session = await composio.create(composioUserID as string, { toolkits: ["dictionary_api"], }); const composioMCPUrl = session.mcp.url; const mcpClient = new MCPClient({ id: composioUserID as string, servers: { dictionary_api: { url: new URL(composioMCPUrl), requestInit: { headers: session.mcp.headers, }, }, }, timeout: 30_000, }); const composioTools = await mcpClient.getTools(); const agent = new Agent({ name: "dictionary_api-mastra-agent", instructions: "You are an AI agent with Dictionary api tools via Composio.", model: "openai/gpt-5", }); let messages: AiMessageType[] = []; const rl = readline.createInterface({ input: process.stdin, output: process.stdout, prompt: "> ", }); rl.prompt(); rl.on("line", async (input: string) => { const trimmed = input.trim(); if (["exit", "quit"].includes(trimmed.toLowerCase())) { rl.close(); return; } messages.push({ id: crypto.randomUUID(), role: "user", content: trimmed }); const { text } = await agent.generate(messages, { toolsets: { dictionary_api: composioTools }, maxSteps: 8, }); if (text) { console.log(`Agent: ${text}\n`); messages.push({ id: crypto.randomUUID(), role: "assistant", content: text }); } rl.prompt(); }); rl.on("close", async () => { await mcpClient.disconnect(); process.exit(0); }); } main(); ``` ## Conclusion You've built a Mastra AI agent that can interact with Dictionary api through Composio's Tool Router. You can extend this further by: - Adding other toolkits like Gmail, Slack, or GitHub - Building a web-based chat interface around this agent - Using multiple MCP endpoints to enable cross-app workflows ## How to build Dictionary api MCP Agent with another framework - [OpenAI Agents SDK](https://composio.dev/toolkits/dictionary_api/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/dictionary_api/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/dictionary_api/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/dictionary_api/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/dictionary_api/framework/codex) - [OpenClaw](https://composio.dev/toolkits/dictionary_api/framework/openclaw) - [Hermes](https://composio.dev/toolkits/dictionary_api/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/dictionary_api/framework/cli) - [Google ADK](https://composio.dev/toolkits/dictionary_api/framework/google-adk) - [LangChain](https://composio.dev/toolkits/dictionary_api/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/dictionary_api/framework/ai-sdk) - [LlamaIndex](https://composio.dev/toolkits/dictionary_api/framework/llama-index) - [CrewAI](https://composio.dev/toolkits/dictionary_api/framework/crew-ai) ## Related Toolkits - [Canvas](https://composio.dev/toolkits/canvas) - Canvas is a learning management system for online courses, assignments, grading, and collaboration. It's trusted by educators and students to streamline virtual classrooms and enhance digital learning. - [Accredible certificates](https://composio.dev/toolkits/accredible_certificates) - Accredible Certificates is a platform for creating and managing digital certificates, badges, and blockchain credentials. It streamlines issuing, tracking, and verifying professional achievements for organizations of any size. - [Api bible](https://composio.dev/toolkits/api_bible) - API.Bible is a developer platform for Scripture content and passage search. Easily integrate Bible verses and translations into your apps or chatbots. - [Blackboard](https://composio.dev/toolkits/blackboard) - Blackboard is a digital learning platform for higher education and schools, offering tools to manage courses, track engagement, and deliver interactive content. It helps institutions improve student outcomes through actionable analytics and in-app guidance. - [Certifier](https://composio.dev/toolkits/certifier) - Certifier is a platform for creating, managing, and issuing digital certificates and credentials. Organizations use it to automate and secure the entire credentialing process. - [Classmarker](https://composio.dev/toolkits/classmarker) - ClassMarker is a professional online quiz maker for business and education. It provides instant grading, flexible test design, and in-depth reporting. - [Coassemble](https://composio.dev/toolkits/coassemble) - Coassemble is a flexible platform for building, managing, and delivering online training courses. It helps teams streamline onboarding, upskilling, and ongoing learning for employees or partners. - [D2lbrightspace](https://composio.dev/toolkits/d2lbrightspace) - D2L Brightspace is a learning management system for delivering and managing online courses and assessments. It helps educators streamline digital teaching, assignments, and communication with students. - [Google Classroom](https://composio.dev/toolkits/google_classroom) - Google Classroom is a free web service for educators and students to manage assignments and communication. It streamlines classroom collaboration and grading, making teaching simpler and more connected. - [Lessonspace](https://composio.dev/toolkits/lessonspace) - Lessonspace is an online collaborative classroom platform offering video, whiteboards, and real-time interaction for educators and students. It streamlines remote teaching with integrated tools for engagement and communication. - [Linguapop](https://composio.dev/toolkits/linguapop) - Linguapop is a web platform for administering language placement tests in English, German, Spanish, Italian, and French. It helps schools and organizations efficiently manage multilingual assessments and analyze results. - [Memberspot](https://composio.dev/toolkits/memberspot) - Memberspot is an online course and video-hosting platform for business learning. It helps teams manage, deliver, and track knowledge efficiently. - [Membervault](https://composio.dev/toolkits/membervault) - Membervault is a platform for hosting courses, memberships, and digital products in one place. It helps you build stronger relationships with your audience by centralizing digital offers and customer engagement. - [Gmail](https://composio.dev/toolkits/gmail) - Gmail is Google's email service with powerful spam protection, search, and G Suite integration. It keeps your inbox organized and makes communication fast and reliable. - [Google Calendar](https://composio.dev/toolkits/googlecalendar) - Google Calendar is a time management service for scheduling meetings, events, and reminders. It streamlines personal and team organization with integrated notifications and sharing options. - [Google Drive](https://composio.dev/toolkits/googledrive) - Google Drive is a cloud storage platform for uploading, sharing, and collaborating on files. It's perfect for keeping your documents accessible and organized across devices. - [Outlook](https://composio.dev/toolkits/outlook) - Outlook is Microsoft's email and calendaring platform for unified communications and scheduling. It helps users stay organized with powerful email, contacts, and calendar management. - [Twitter](https://composio.dev/toolkits/twitter) - Twitter is a social media platform for sharing real-time updates, conversations, and news. Stay connected, informed, and engaged with communities worldwide. - [Google Sheets](https://composio.dev/toolkits/googlesheets) - Google Sheets is a cloud-based spreadsheet tool for real-time collaboration and data analysis. It lets teams work together from anywhere, updating information instantly. - [Supabase](https://composio.dev/toolkits/supabase) - Supabase is an open-source backend platform offering scalable Postgres databases, authentication, storage, and real-time APIs. It lets developers build modern apps without managing infrastructure. ## Frequently Asked Questions ### What are the differences in Tool Router MCP and Dictionary api MCP? With a standalone Dictionary api MCP server, the agents and LLMs can only access a fixed set of Dictionary api tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Dictionary api and many other apps based on the task at hand, all through a single MCP endpoint. ### Can I use Tool Router MCP with Mastra AI? Yes, you can. Mastra AI fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Dictionary api tools. ### Can I manage the permissions and scopes for Dictionary api while using Tool Router? Yes, absolutely. You can configure which Dictionary api scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do. ### How safe is my data with Composio Tool Router? All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Dictionary api data and credentials are handled as safely as possible. --- [See all toolkits](https://composio.dev/toolkits) ยท [Composio docs](https://docs.composio.dev/llms.txt)