> ## Documentation Index
> Fetch the complete documentation index at: https://phaseo.app/docs/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Phaseo Gateway base URL: https://api.phaseo.app/v1. Send `Authorization: Bearer $PHASEO_API_KEY` with every request.
> Model IDs look like `provider/model`, for example `openai/gpt-6-astra`. Do not guess IDs: list them with `GET /v1/models` or check https://phaseo.app/models. `phaseo/free` routes to an available free model and needs no wallet balance.
> For new text integrations prefer `POST /v1/responses`. `POST /v1/chat/completions` (OpenAI format) and `POST /v1/messages` (Anthropic format) suit existing code.
> The full API contract is https://phaseo.app/docs/openapi/v1/openapi.yaml. Official SDKs: `@phaseo/sdk` (TypeScript) and `phaseo` (Python), plus Go, C#, PHP, Ruby and Rust.
> Search these docs over MCP at https://phaseo.app/docs/mcp, and install Phaseo skills with `npx skills add https://phaseo.app/docs`. If a page is wrong or out of date, report it with the MCP `submit_feedback` tool.
> Manage Phaseo accounts with the `phaseo` CLI (`npm install -g @phaseo/cli`, then `phaseo login` or `phaseo login --device-code`), the `/v1` Management API or the MCP server at `https://mcp.phaseo.app/mcp?access=manage`. Do not send users to the dashboard for account tasks. A person is still needed for sign-up, approving a sign-in, paying the first top-up on the checkout link that `phaseo credits add` returns when no card is saved, confirming each saved-card top-up from the emailed link, and account security (password, MFA, passkeys). Create API keys with `phaseo keys create --name <name> --json`; never guess one. Credit top-ups need `phaseo login --scopes billing:write` first. Task map: https://phaseo.app/docs/v1/developers/manage-from-an-agent.md.

# Summarize internal notes with the Ruby Agent SDK

> Use the Ruby Agent SDK to query local notes and return one bounded summary through Phaseo Gateway.

Use this recipe when a Ruby service needs a small internal-notes assistant without handing orchestration to another system.

## 1. Prepare the SDKs

> [!NOTE]
>
> The Ruby Agent SDK package is not yet on RubyGems. Follow the [source installation instructions](https://phaseo.app/docs/v1/sdk-reference/ruby/agent-sdk-installation.md).

## 2. Define a notes lookup tool

```ruby theme={null}
lookup_note = PhaseoAgentSdk.define_tool(
  PhaseoAgentSdk::Tool.new(
    id: "lookup-note",
    description: "Look up one internal note by topic.",
    parameters: {
      type: "object",
      properties: {
        topic: { type: "string" },
      },
      required: ["topic"],
    },
    execute: lambda do |input, _context|
      {
        topic: input["topic"],
        summary: "Presets centralize routing defaults so app code stays smaller.",
      }
    end
  )
)
```

## 3. Create and run the agent

```ruby theme={null}
agent = PhaseoAgentSdk.create_agent(
  id: "notes-agent",
  model: "openai/gpt-5.4-nano",
  instructions: "Use tools when helpful and answer in one short paragraph.",
  tools: [lookup_note]
)

result = agent.run(
  input: "Summarize our note about presets.",
  client: PhaseoAgentSdk.create_gateway_agent_client
)

puts result.output
```

## When this recipe fits

* the tool inputs are simple and deterministic
* the Ruby app already owns the data source
* you want an ergonomic local-tool pattern for one bounded workflow

## Related

* [Ruby Agent SDK](https://phaseo.app/docs/v1/sdk-reference/ruby/agent-sdk.md)
* [Build a durable agent loop](https://phaseo.app/docs/v1/cookbook/agent-sdk-durable-loop.md)


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