> ## 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 If a page is wrong or out of date, report it with the MCP `submit_feedback` tool.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.

# Mastra

> Use Phaseo models inside Mastra agents and workflows.

Mastra works with AI SDK providers, so the shortest path is to create an OpenAI-compatible provider that points at Phaseo.

## Install

```bash theme={null}
npm install @mastra/core @ai-sdk/openai ai
```

## Configure an agent

```ts theme={null}
import { Agent } from "@mastra/core/agent";
import { createOpenAI } from "@ai-sdk/openai";

const phaseo = createOpenAI({
	apiKey: process.env.PHASEO_API_KEY,
	baseURL: "https://api.phaseo.app/v1",
	compatibility: "compatible",
});

export const agent = new Agent({
	name: "support-agent",
	instructions: "Answer in two short paragraphs.",
	model: phaseo("openai/gpt-5-nano"),
});
```

## Notes

* Use the base URL only, not `/chat/completions` or `/responses`.
* Mastra agent behavior depends on the AI SDK provider path. Test tools and streaming before production.
* Use Phaseo routing controls at the request level or through presets when you need provider preferences.

## Related

* [AI SDK](https://phaseo.app/docs/v1/guides/integrations/ai-sdk.md)
* [Presets](https://phaseo.app/docs/v1/guides/presets.md)
* [Tool Calling](https://phaseo.app/docs/v1/guides/tool-calling.md)


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