Relay-E

This walks through the fastest path to a working agent run. We'll define a simple example skill and send it a message.

1. Install (1 min)

git clone https://github.com/belulok/relay-e.git && cd relay-e
nvm use
npm install
cp .env.example .env

Edit .env and add one provider key:

.env

DEV_API_KEY=sk_dev_local_change_me
OPENROUTER_API_KEY=sk-or-v1-...

2. Boot the stack (1 min)

npm run stack:up
npm run db:generate && npm run db:migrate
npm run dev

The API is up at http://localhost:3001. Open /docs for the interactive Scalar UI.

3. Send a sync message (1 min)

curl -s -X POST http://localhost:3001/v1/sessions/demo/messages \
  -H "Authorization: Bearer sk_dev_local_change_me" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "How much did I spend on food last month?",
    "skills": ["financial-advisor"]
  }' | jq

You'll get back something like:

{
  "id": "msg_...",
  "session_id": "demo",
  "role": "assistant",
  "content": [{ "type": "text", "text": "Last month you spent..." }],
  "usage": { "tokens_in": 1234, "tokens_out": 215, "cost_usd": 0.003 },
  "finish_reason": "stop",
  "tool_calls": [
    { "name": "analyze_spending", "input": { "days": 30 }, "output": {...} }
  ],
  "context": { "sources": ["skill_guardrails"] }
}

The agent decided to call analyze_spending, got back data, and used it to answer. You wrote zero orchestration code.

4. Stream it (1 min)

curl -N -X POST http://localhost:3001/v1/sessions/demo/messages \
  -H "Authorization: Bearer sk_dev_local_change_me" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "Show my balance and top spending categories.",
    "skills": ["financial-advisor"],
    "stream": true
  }'

You'll see SSE events flow in:

event: thinking
data: {"step":"resolving_context"}

event: context_resolved
data: {"sources":["skill_guardrails"],"tokenEstimate":12}

event: tool_call
data: {"tool_call_id":"tc_...","name":"get_balance","input":{...}}

event: tool_result
data: {"tool_call_id":"tc_...","name":"get_balance","output":{...}}

event: usage
data: {"usage":{"tokens_in":2103,"tokens_out":312,"cost_usd":0.005},"model":"claude-sonnet-4-6"}

event: text
data: {"text":"Your balance is $4,231.55..."}

5. Add your own skill (1 min)

Open apps/api/src/bootstrap/registries.ts:

tools.register(defineTool({
  name: "get_weather",
  description: "Return current weather for a city.",
  inputSchema: z.object({ city: z.string() }),
  execute: async ({ city }) => ({ city, temp_c: 22, condition: "sunny" }),
}));

skills.register(defineSkill({
  name: "weather-bot",
  description: "Answers questions about the weather.",
  systemPrompt: "You are a helpful weather assistant.",
  toolNames: ["get_weather"],
  preferredTier: "fast",
}));

Restart npm run dev, then:

curl -X POST http://localhost:3001/v1/sessions/demo/messages \
  -H "Authorization: Bearer sk_dev_local_change_me" \
  -d '{"prompt":"What is the weather in Tokyo?","skills":["weather-bot"]}'

The new skill is auto-listed in /v1/skills, the new tool in /v1/tools, and both appear in /openapi.json and the /docs UI without any restart of those pages.

Quickstart

1. Install (1 min)

2. Boot the stack (1 min)

3. Send a sync message (1 min)

4. Stream it (1 min)

5. Add your own skill (1 min)

What's next

Concepts → Skills

Concepts → Tools

Guides → Connecting your data

Integration → Use it from your app

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