Edge-first AI agents for Cloudflare Workers.
The Mastra for developers who deploy on Cloudflare.
Honi is a lightweight framework for building agentic AI applications on Cloudflare Workers. It combines Hono for routing, Durable Objects for persistent memory, and the Vercel AI SDK for multi-provider LLM support — all in a single createAgent() call.
bun add honidev// src/index.ts
import { createAgent, tool, z } from 'honidev';
const searchCRM = tool({
name: 'search_crm',
description: 'Search HubSpot for deal info',
input: z.object({ query: z.string() }),
handler: async ({ query }) => {
// Your CRM logic here
return { results: [] };
},
});
const salesCoach = createAgent({
name: 'sales-coach',
model: 'claude-sonnet-4-5',
memory: { enabled: true },
tools: [searchCRM],
system: 'You are a real-time sales coach.',
binding: 'SALES_COACH_DO',
});
export default { fetch: salesCoach.fetch };
export const SalesCoachDO = salesCoach.DurableObject;# wrangler.toml
name = "sales-coach-agent"
main = "src/index.ts"
compatibility_date = "2024-12-01"
[[durable_objects.bindings]]
name = "SALES_COACH_DO"
class_name = "SalesCoachDO"
[[migrations]]
tag = "v1"
new_classes = ["SalesCoachDO"]wrangler deploycurl -X POST https://your-worker.workers.dev/chat \
-H "Content-Type: application/json" \
-H "X-Thread-Id: thread-123" \
-d '{"message": "What deals are closing this week?"}'Honi supports four tiers of memory, all opt-in:
| Tier | Backing | Survives DO eviction? | Queryable across threads? |
|---|---|---|---|
| Working | Durable Object storage | No | No |
| Episodic | D1 | Yes | Yes |
| Semantic | Vectorize + Workers AI | Yes | Yes (similarity search) |
| Graph | edgraph (DO) | Yes | Yes (entity/relationship traversal) |
Add bindings to your wrangler.toml:
[[d1_databases]]
binding = "DB"
database_name = "honi-memory"
database_id = "YOUR_DB_ID"
[[vectorize]]
binding = "VECTORIZE"
index_name = "honi-semantic"
dimensions = 768
metric = "cosine"
[ai]
binding = "AI"
# Graph memory — deploy edgraph and add a service binding (or use urlEnvVar for HTTP)
[[services]]
binding = "EDGRAPH"
service = "edgraph"Run the D1 migration:
wrangler d1 migrations apply honi-memoryconst agent = createAgent({
name: 'my-agent',
model: 'claude-sonnet-4-5',
memory: {
enabled: true,
episodic: { enabled: true },
semantic: { enabled: true, topK: 3 },
graph: {
enabled: true,
graphId: 'my-knowledge-base',
binding: 'EDGRAPH', // CF service binding (preferred)
// urlEnvVar: 'EDGRAPH_URL', // or HTTP URL via env var
apiKeyEnvVar: 'EDGRAPH_API_KEY',
contextDepth: 1, // hop depth for context expansion
},
},
system: 'You are a helpful assistant.',
});All tiers are fully opt-in. Missing bindings log a warning and fall back gracefully.
- On each request: past messages load from D1 (episodic), the user message is embedded and searched against Vectorize (semantic), and any entity IDs found in semantic results are expanded via graph traversal. All context is prepended to the system prompt.
- After each response: the conversation turn is saved to D1 and both user + assistant messages are embedded and upserted to Vectorize for future retrieval.
Graph memory is most powerful when tools write entities as they discover them:
import { tool, GraphMemory } from 'honidev';
const myTool = tool({
name: 'lookup_customer',
description: 'Look up a customer by ID',
input: z.object({ customerId: z.string() }),
handler: async (input, ctx) => {
const customer = await db.getCustomer(input.customerId);
// Write to graph — ctx.graph is the live GraphMemory instance
if (ctx?.graph && customer) {
await ctx.graph.upsertNode(customer.id, 'Customer', {
name: customer.name,
plan: customer.plan,
});
if (customer.accountManagerId) {
await ctx.graph.upsertEdge(
customer.id,
customer.accountManagerId,
'managed_by',
);
}
}
return customer;
},
});ctx.graph is the live GraphMemory instance bound to the current agent. Entities written here are immediately available for future context retrieval.
GraphMemory can also be used outside of an agent — as a shared knowledge base across multiple services:
import { GraphMemory } from 'honidev';
const graph = new GraphMemory({
graphId: 'crm',
url: 'https://edgraph.myapp.workers.dev',
apiKey: process.env.EDGRAPH_API_KEY,
});
await graph.upsertNode('alice', 'Person', { role: 'CTO', company: 'ACME' });
await graph.upsertNode('acme', 'Company', { industry: 'SaaS' });
await graph.upsertEdge('alice', 'acme', 'works_at');
// Get context block for LLM injection
const context = await graph.toContext(['alice'], 2);
// "[Knowledge graph context:]
// - (Person:alice) {role="CTO", company="ACME"}
// → [works_at] → (Company:acme)
// [End graph context]"
// Traversal
const path = await graph.shortestPath('alice', 'bob');
const neighbours = await graph.getNeighbours('alice', 'out', ['manages']);An agent is created with createAgent() and bundles:
- A Hono-powered HTTP API with
/chat,/historyroutes - A Durable Object class for persistent, per-thread state
- An LLM connection with automatic tool-calling loops and streaming
Define tools with Zod schemas. Honi auto-generates the JSON schema for the LLM and validates inputs at runtime:
const weatherTool = tool({
name: 'get_weather',
description: 'Get current weather for a city',
input: z.object({
city: z.string().describe('City name'),
units: z.enum(['celsius', 'fahrenheit']).default('celsius'),
}),
handler: async ({ city, units }) => {
return { temp: 22, city, units };
},
});When memory: { enabled: true }, conversation history is persisted in Durable Object storage. Each thread (identified by X-Thread-Id header) gets its own isolated memory.
POST /chat— send a message, get a streaming responseGET /history?threadId=xxx— retrieve conversation historyDELETE /history?threadId=xxx— clear a thread's history
Honi uses the Vercel AI SDK under the hood. Model routing is automatic based on the model ID prefix:
| Model prefix | Provider | Env var / binding | Example model |
|---|---|---|---|
claude-* |
Anthropic | ANTHROPIC_API_KEY |
claude-sonnet-4-5 |
gpt-*, o1, o3-* |
OpenAI | OPENAI_API_KEY |
gpt-4o, o3-mini |
gemini-* |
GOOGLE_AI_API_KEY |
gemini-2.5-flash-preview |
|
groq/* |
Groq | GROQ_API_KEY |
groq/llama-3.3-70b-versatile |
deepseek-* |
DeepSeek | DEEPSEEK_API_KEY |
deepseek-chat, deepseek-reasoner |
mistral-*, codestral-*, pixtral-* |
Mistral | MISTRAL_API_KEY |
mistral-large-latest |
grok-* |
xAI | XAI_API_KEY |
grok-3, grok-3-mini |
sonar*, perplexity/* |
Perplexity | PERPLEXITY_API_KEY |
sonar-pro, sonar-reasoning |
together/* |
Together AI | TOGETHER_API_KEY |
together/meta-llama/Llama-3.3-70B-Instruct-Turbo |
command-* |
Cohere | COHERE_API_KEY |
command-r-plus, command-a-03-2025 |
azure/* |
Azure OpenAI | AZURE_OPENAI_API_KEY + AZURE_OPENAI_ENDPOINT |
azure/gpt-4o |
@cf/* |
Workers AI | AI binding in wrangler.toml |
@cf/meta/llama-3.1-8b-instruct |
All non-core providers use optional peer dependencies — zero bundle cost unless installed. Set API keys as Cloudflare Worker secrets:
wrangler secret put ANTHROPIC_API_KEY
wrangler secret put GOOGLE_AI_API_KEY
# etc.Non-Anthropic/OpenAI/Google providers require their AI SDK package:
npm install @ai-sdk/groq # Groq
npm install @ai-sdk/deepseek # DeepSeek
npm install @ai-sdk/mistral # Mistral
npm install @ai-sdk/xai # xAI
npm install @ai-sdk/perplexity # Perplexity
npm install @ai-sdk/togetherai # Together AI
npm install @ai-sdk/cohere # Cohere
npm install @ai-sdk/azure # Azure OpenAI
npm install @ai-sdk/cloudflare # Workers AIUse any Workers AI model by prefixing with @cf/:
# wrangler.toml
[ai]
binding = "AI"const agent = createAgent({
name: 'my-agent',
model: '@cf/meta/llama-3.1-8b-instruct', // Uses Workers AI
system: 'You are a helpful assistant.',
});Workers AI support requires the optional @ai-sdk/cloudflare package:
npm install @ai-sdk/cloudflareRoute all LLM calls through Cloudflare AI Gateway for logging, rate limiting, and caching at the edge:
const agent = createAgent({
name: 'my-agent',
model: 'claude-sonnet-4-5',
observability: {
aiGateway: {
accountId: 'your-account-id',
gatewayId: 'your-gateway-id',
},
},
system: 'You are a helpful assistant.',
});
// All LLM calls now route through CF AI Gateway for observabilityAll responses stream via the AI SDK data protocol, compatible with the useChat() hook from ai/react:
import { useChat } from 'ai/react';
const { messages, input, handleSubmit } = useChat({
api: 'https://your-worker.workers.dev/chat',
headers: { 'X-Thread-Id': 'thread-123' },
});| Feature | Honi | Mastra | LangChain |
|---|---|---|---|
| Runtime | Cloudflare Workers | Node.js | Node.js |
| Memory | Durable Objects | Postgres / Redis | Various |
| Streaming | SSE (AI SDK) | SSE | Callbacks |
| Deploy | wrangler deploy |
Self-host | Self-host |
| Cold start | ~0 ms (edge) | Seconds | Seconds |
| Bundle size | Minimal | Heavy | Heavy |
| Tool system | Zod-native | Zod-native | Mixed |
| Framework | Hono | Express / Hono | Custom |
Ready-to-deploy example projects in the examples/ directory:
| Example | Description |
|---|---|
01-simple-agent |
Minimal hello-world agent with Durable Object memory |
02-rag-agent |
Full tiered memory — episodic (D1) + semantic RAG (Vectorize) |
03-research-workflow |
Multi-step research pipeline using Cloudflare Workflows |
Each example includes a wrangler.toml, package.json, and README with setup instructions.
Honi wraps Cloudflare Workflows with a simple workflow() + step() API for durable, multi-step agent pipelines.
import { workflow, step } from 'honidev';
const IngestWorkflow = workflow({
steps: [
step({ name: 'fetch-data', retries: { limit: 3, backoff: 'exponential' } }, async (input, step) => {
const res = await fetch(input.url);
return res.json();
}),
step({ name: 'process', timeout: '60s' }, async (data, step) => {
return { processed: true, items: data.length };
}),
],
onComplete: async (result, env) => {
console.log('Pipeline complete:', result);
},
onError: async (error, env) => {
console.error('Pipeline failed:', error.message);
},
});
export { IngestWorkflow };Add to wrangler.toml:
[[workflows]]
name = "ingest-workflow"
binding = "INGEST_WORKFLOW"
class_name = "IngestWorkflow"Honi includes a CLI for scaffolding and managing projects.
# Install globally
npm install -g honidev
# Create a new project
honi new my-sales-coach
# Start local dev server
honi dev
# Deploy to Cloudflare Workers
honi deployhoni new generates a ready-to-run project with src/index.ts, wrangler.toml, tsconfig.json, and package.json.
Honi emits structured events for every agent request, tool call, memory operation, and workflow step.
const agent = createAgent({
name: 'my-agent',
model: 'claude-sonnet-4-5',
observability: {
logLevel: 'debug',
onEvent: (event) => {
// Send to your logging/analytics service
console.log(event.type, event.durationMs);
},
aiGateway: {
accountId: 'your-cf-account-id',
gatewayId: 'your-gateway-id',
},
},
});| Event | Emitted When |
|---|---|
agent.request |
Incoming chat request |
agent.response |
Response stream complete |
tool.call |
Tool execution starts |
tool.result |
Tool execution finishes |
memory.load |
Memory loaded from storage |
memory.save |
Memory persisted |
workflow.start |
Workflow begins |
workflow.step |
Workflow step executes |
workflow.complete |
Workflow finishes |
workflow.error |
Workflow errors |
Set observability.aiGateway to route LLM calls through Cloudflare AI Gateway for logging, rate limiting, and caching at the edge.
| Option | Type | Default | Description |
|---|---|---|---|
name |
string |
— | Agent name |
model |
string |
— | Model ID (claude-sonnet-4-5, gpt-4o) |
system |
string |
— | System prompt |
memory |
MemoryConfig |
{} |
Memory configuration (see Phase 2) |
tools |
ToolDefinition[] |
[] |
Agent tools |
binding |
string |
"AGENT" |
Durable Object binding name |
maxSteps |
number |
10 |
Max tool-calling loop iterations |
Returns { fetch, DurableObject }.
| Option | Type | Description |
|---|---|---|
name |
string |
Tool name (sent to LLM) |
description |
string |
What the tool does |
input |
ZodType |
Zod schema for tool input |
handler |
(input) => Promise<unknown> |
Tool implementation |
MIT
Honi is designed to fit comfortably within Cloudflare Workers' limits:
| Component | Size |
|---|---|
| Honi library (dist/) | ~30 KB |
| Full demo app (with AI SDK) | 691 KB uncompressed |
| Gzip compressed | 123 KB |
| CF Workers limit | 1 MB compressed |
You're using ~12% of the limit with a full-featured agent including all AI SDK providers.
- Only import the providers you need (
@ai-sdk/anthropicOR@ai-sdk/openai, not both) - Use Workers AI (
@cf/models) to skip external provider SDKs entirely - Tree-shaking works — unused features don't add to bundle size
Honi agents can expose their tools as MCP endpoints, allowing connection from Claude Desktop, Cursor, and other MCP-compatible clients.
| Endpoint | Method | Description |
|---|---|---|
/mcp |
POST | JSON-RPC 2.0 MCP endpoint |
/mcp/tools |
GET | List available tools (convenience) |
For remote connections (Cursor, custom clients, any non-local use) you should lock down /mcp with a Bearer token. Set mcp.secretEnvVar in your agent config:
const agent = createAgent({
name: 'my-agent',
model: 'claude-sonnet-4-5',
tools: [searchDocs],
mcp: { secretEnvVar: 'MCP_SECRET' },
})Then set the secret via Wrangler:
wrangler secret put MCP_SECRETClients send Authorization: Bearer <secret> on every request. If secretEnvVar is not set, /mcp is unauthenticated — fine for local Claude Desktop (stdio transport), but don't expose it publicly without this.
Add to your Claude Desktop MCP config:
{
"mcpServers": {
"my-honi-agent": {
"url": "https://my-agent.workers.dev/mcp"
}
}
}For authenticated remote connections:
{
"mcpServers": {
"my-honi-agent": {
"url": "https://my-agent.workers.dev/mcp",
"headers": {
"Authorization": "Bearer your-secret-here"
}
}
}
}Honi supports agent-to-agent communication for building complex agentic workflows.
import { routeToAgent, callAgentTool, listAgentTools } from 'honidev';
// Send a message to another agent
const response = await routeToAgent(env, { binding: 'OTHER_AGENT' }, 'Hello!');
// Call a specific tool on another agent
const result = await callAgentTool(env, { binding: 'OTHER_AGENT' }, 'search', { query: 'test' });
// List available tools from another agent
const tools = await listAgentTools(env, { binding: 'OTHER_AGENT' });[[durable_objects.bindings]]
name = "MY_AGENT"
class_name = "MyAgentDO"
[[durable_objects.bindings]]
name = "OTHER_AGENT"
class_name = "OtherAgentDO"