jwynia/mastra-hono
Develop AI agents, tools, and workflows with Mastra v1 Beta and Hono servers. This skill should be used when creating Mastra agents, defining tools with Zod schemas, building workflows with step data flow, setting up Hono API servers with Mastra adapters, or implementing agent networks. Keywords: mastra, hono, agent, tool, workflow, AI, LLM, typescript, API, MCP.
npx skills add https://github.com/jwynia/agent-skills --skill mastra-hono
Build production-ready AI agents, tools, and workflows using Mastra v1 Beta with Hono API servers. This skill covers the complete stack from agent definition to deployment.
Target version: Mastra v1 Beta (stable release expected January 2026)
Use when:
Do NOT use when:
# Install v1 Beta packages
npm install @mastra/core@beta @mastra/hono@beta
npm install @ai-sdk/openai # or other provider
npm install zod hono @hono/node-server
// src/mastra/tools/weather-tool.ts
import { createTool } from "@mastra/core/tools";
import { z } from "zod";
export const weatherTool = createTool({
id: "get-weather",
description: "Fetches current weather for a location",
inputSchema: z.object({
location: z.string().describe("City name, e.g., 'Seattle'"),
}),
outputSchema: z.object({
temperature: z.number(),
conditions: z.string(),
}),
// v1 Beta signature: (inputData, context)
execute: async (inputData, context) => {
const { location } = inputData;
const { abortSignal } = context;
if (abortSignal?.aborted) throw new Error("Aborted");
// Fetch weather data...
return { temperature: 72, conditions: "sunny" };
},
});
// src/mastra/agents/weather-agent.ts
import { Agent } from "@mastra/core/agent";
import { openai } from "@ai-sdk/openai";
import { weatherTool } from "../tools/weather-tool.js";
export const weatherAgent = new Agent({
name: "weather-agent",
instructions: "You are a helpful weather assistant.",
model: openai("gpt-4o-mini"),
tools: { weatherTool }, // Object, not array
});
// src/mastra/index.ts
import { Mastra } from "@mastra/core/mastra";
import { weatherAgent } from "./agents/weather-agent.js";
export const mastra = new Mastra({
agents: { weatherAgent },
});
// src/index.ts
import { serve } from "@hono/node-server";
import { Hono } from "hono";
import { MastraServer } from "@mastra/hono";
import { mastra } from "./mastra/index.js";
const app = new Hono();
const server = new MastraServer({ app, mastra });
await server.init();
app.get("/", (c) => c.text("Mastra + Hono Server"));
serve({ fetch: app.fetch, port: 3000 });
console.log("Server running at http://localhost:3000");
// Agent endpoint: POST /api/agents/weather-agent/generate
import { Agent } from "@mastra/core/agent";
const agent = new Agent({
name: "my-agent", // Required: unique identifier
instructions: "You are a helpful assistant.", // Required: system prompt
model: openai("gpt-4o-mini"), // Required: LLM model
tools: { weatherTool, searchTool }, // Optional: object with named tools
});
// Model routing (1113+ models from 53 providers)
model: "openai/gpt-4o-mini"
model: "anthropic/claude-3-5-sonnet"
model: "google/gemini-2.5-flash"
// Model fallbacks for resilience
model: [
{ model: "anthropic/claude-3-opus", maxRetries: 3 },
{ model: "openai/gpt-4o", maxRetries: 2 },
{ model: "google/gemini-pro", maxRetries: 1 },
]
// Agent execution with memory
const response = await agent.generate("Remember my name is Alex", {
memory: {
thread: "conversation-123", // Isolates conversation
resource: "user-456", // Associates with user
},
});
// v1 Beta: execute(inputData, context)
execute: async (inputData, context) => {
const { location } = inputData; // First parameter: parsed input
const { mastra, runtimeContext, abortSignal } = context; // Second: context
// Access nested agents via mastra
const helper = mastra?.getAgent("helperAgent");
// Always check abort signal for long operations
if (abortSignal?.aborted) throw new Error("Aborted");
return { temperature: 72, conditions: "sunny" };
}
// WRONG for v1 Beta:
execute: async ({ context }) => { ... } // This is stable 0.24.x signature
This is where most errors occur. See references/workflow-data-flow.md for complete patterns.
import { createWorkflow, createStep } from "@mastra/core/workflows";
const step1 = createStep({
id: "step-1",
inputSchema: z.object({ message: z.string() }),
outputSchema: z.object({ formatted: z.string() }),
execute: async ({ inputData }) => {
// inputData = workflow input (for first step)
return { formatted: inputData.message.toUpperCase() };
},
});
const step2 = createStep({
id: "step-2",
inputSchema: z.object({ formatted: z.string() }), // MUST match step1 output
outputSchema: z.object({ emphasized: z.string() }),
execute: async ({ inputData }) => {
// inputData = step1's return value directly
return { emphasized: `${inputData.formatted}!!!` };
},
});
const workflow = createWorkflow({
id: "my-workflow",
inputSchema: z.object({ message: z.string() }), // MUST match step1 input
outputSchema: z.object({ emphasized: z.string() }), // MUST match final output
})
.then(step1)
.then(step2)
.commit();
Schema matching rules:
| Rule | Description |
|------|-------------|
| Workflow input → Step 1 input | Must match exactly |
| Step N output → Step N+1 input | Must match exactly |
| Final step output → Workflow output | Must match exactly |
Data access in steps:
execute: async ({
inputData, // Previous step's output (or workflow input for step 1)
getStepResult, // Access ANY step's output by ID
getInitData, // Get original workflow input
mastra, // Access agents, tools, storage
}) => {
const step1Result = getStepResult("step-1");
const originalInput = getInitData();
return { result: inputData.formatted };
}
import { MastraServer } from "@mastra/hono";
const app = new Hono();
const server = new MastraServer({ app, mastra });
await server.init();
// Endpoints auto-registered:
// POST /api/agents/{agent-name}/generate
// POST /api/agents/{agent-name}/stream
// POST /api/workflows/{workflow-id}/start
Custom route prefix:
const server = new MastraServer({
app,
mastra,
prefix: "/v1/ai" // Routes at /v1/ai/agents/...
});
Custom API routes:
import { registerApiRoute } from "@mastra/core/server";
registerApiRoute("/my-custom-route", {
method: "POST",
handler: async (c) => {
const mastra = c.get("mastra");
const agent = mastra.getAgent("my-agent");
const result = await agent.generate("Hello");
return c.json({ response: result.text });
},
});
| Topic | Wrong | Correct |
|-------|-------|---------|
| Imports | import { Agent } from "@mastra/core" | import { Agent } from "@mastra/core/agent" |
| Tools array | tools: [tool1, tool2] | tools: { tool1, tool2 } |
| Memory context | { threadId: "123" } | { memory: { thread: "123", resource: "user" } } |
| Workflow data | context.steps.step1.output | inputData or getStepResult("step-1") |
| After parallel | inputData.result | inputData["step-id"].result |
| After branch | inputData.result | inputData["step-id"]?.result (optional) |
| Nested agents | import agent; agent.generate() | mastra.getAgent("name").generate() |
| State mutation | state.counter++ | setState({ ...state, counter: state.counter + 1 }) |
| v1 tool exec | execute: async ({ context }) | execute: async (inputData, context) |
| Script | Purpose | Usage |
|--------|---------|-------|
| scaffold-project.ts | Create new Mastra+Hono project | deno run --allow-all scripts/scaffold-project.ts --name my-project |
| scaffold-agent.ts | Create agent with tools | deno run --allow-all scripts/scaffold-agent.ts --name weather |
| scaffold-workflow.ts | Create workflow with steps | deno run --allow-all scripts/scaffold-workflow.ts --name process-data |
| scaffold-tool.ts | Create tool with schemas | deno run --allow-all scripts/scaffold-tool.ts --name fetch-weather |
| validate-workflow-schemas.ts | Validate step schema matching | deno run --allow-read scripts/validate-workflow-schemas.ts ./src/mastra/workflows/ |
| check-version-patterns.ts | Detect v1/stable pattern mixing | deno run --allow-read scripts/check-version-patterns.ts ./src/mastra/ |
references/workflow-data-flow.md - Complete data flow patterns (CRITICAL)references/common-mistakes.md - Extended anti-patterns and fixesreferences/agent-patterns.md - Agent definition deep-divereferences/tool-patterns.md - Tool signatures, wrappersreferences/hono-server-patterns.md - Server setup, routes, middlewarereferences/testing-patterns.md - Vitest setup, mocking LLMsreferences/mcp-server-patterns.md - Model Context Protocol authoringreferences/agent-networks.md - Multi-agent collaboration, A2Areferences/rag-memory-patterns.md - Vector stores, embeddings, memoryreferences/context-network-memory.md - Context networks for agent memoryassets/agent-template.ts - Agent boilerplateassets/tool-template.ts - Tool boilerplate (v1 signature)assets/workflow-template.ts - Workflow boilerplateassets/hono-server-template.ts - Hono+Mastra server setupassets/vitest-setup-template.ts - Test configurationTake jwynia/mastra-hono from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.
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Without those the skill loads but fails at the first command.