AgentChatAppEnvironment

Package: flyte.ai.chat

An :class:~flyte.app.AppEnvironment that spins up a FastAPI chat interface backed by any object satisfying the :class:Agent protocol.

Parameters

agent: Any object implementing the :class:Agent protocol. title: Title displayed in the UI header and browser tab. Defaults to the environment name. subtitle: Optional short subtitle displayed below the title in the header area. Use it to explain what the agent does. prompt_nudges: Optional list of prompt-nudge cards shown before the first message. Each entry is a dict with "label" (short card title) and "prompt" (the query text sent when clicked). theme: Optional :class:CustomTheme instance that controls the UI accent colors via human-readable attributes. When provided, the theme CSS is generated automatically and prepended to any custom_css. custom_css: Optional CSS string appended after the default styles (and after theme CSS, if a theme is provided). Use this for fine-grained overrides beyond what :class:CustomTheme exposes. logo_url: Optional URL to an image displayed to the left of the title in the header bar. When None (default), no logo is shown. additional_buttons: Optional list of action-button dicts rendered to the right of the Send button. Each dict must have "button_text" and "button_url" keys. The first entry is displayed as a prominent primary button; any extra entries appear in a drop-up menu accessed via a chevron. passthrough_auth: When True, the FastAPI app initializes flyte.init_passthrough at startup and adds FastAPIPassthroughAuthMiddleware so incoming Authorization / cookie headers are forwarded to Flyte remote calls. Enable this when using CodeModeAgent with @env.task tools — nested task execution needs caller credentials (same pattern as FlyteWebhookAppEnvironment). passthrough_auth_excluded_paths: Paths skipped by passthrough middleware. When omitted, defaults include the HTML shell (/), /api/tools, /api/nudges, health, and docs routes so the sidebar and nudges load without Authorization headers; /api/chat still requires credentials. Only used when passthrough_auth is True. task_entrypoint: Optional Flyte task used as the chat handler entrypoint.

When set, ``/api/chat`` calls the task (via ``task_entrypoint.aio``)
instead of calling ``agent.run`` directly. This is useful for agents
whose tool calls must run under a parent task context (e.g. a
``CodeModeAgent`` using durable ``@env.task`` tools). When streaming
chat (``stream: true``), progress lines use :meth:`~flyte.remote.Run.watch`
on the returned run (first ``RUNNING`` → ``generating_code``, next →
``executing``). Fine-grained codemode phases still require
``agent.run`` in the web process, or future worker-side signaling.

The entrypoint may accept either:

- ``(message: str, history: list[dict[str, str]])``; or
- ``(message: str)``.

The return value may be an :class:`~flyte.ai.agents.protocol.AgentResult`,
a dict with keys like ``summary``/``charts``/``code``, or a plain string
(treated as ``summary``).

Parameters

class AgentChatAppEnvironment(
    name: str,
    depends_on: List[Environment],
    pod_template: Optional[Union[str, PodTemplate]],
    description: Optional[str],
    secrets: Optional[SecretRequest],
    env_vars: Optional[Dict[str, str]],
    resources: Optional[Resources],
    interruptible: bool,
    image: Union[str, Image, Literal['auto'], None],
    include: Tuple[str, ...],
    port: int | Port,
    args: *args,
    command: Optional[Union[List[str], str]],
    requires_auth: bool,
    scaling: Scaling,
    domain: Domain | None,
    links: List[Link],
    parameters: List[Parameter],
    cluster_pool: str,
    timeouts: Timeouts,
    type: str,
    agent: Any,
    title: str | None,
    subtitle: str | None,
    prompt_nudges: list[dict[str, str]],
    theme: CustomTheme | None,
    custom_css: str,
    logo_url: str | None,
    additional_buttons: list[dict[str, str]],
    passthrough_auth: bool,
    passthrough_auth_excluded_paths: frozenset[str] | None,
    task_entrypoint: Any | None,
    _caller_frame: inspect.FrameInfo | None,
)

Properties

Methods

add_dependency()

def add_dependency(
    env: Environment,
)

Add one or more environment dependencies so they are deployed together.

When you deploy this environment, any environments added via add_dependency will also be deployed. This is an alternative to passing depends_on=[...] at construction time, useful when the dependency is defined after the environment is created.

Duplicate dependencies are silently ignored. An environment cannot depend on itself.

build_fastapi_app()

def build_fastapi_app()

Construct the FastAPI application (routes, HTML shell, optional auth).

Useful for tests and advanced mounting; the deployed server uses this via :meth:_fastapi_server.

clone_with()

def clone_with(
    name: str,
    image: Optional[Union[str, Image, Literal['auto']]],
    resources: Optional[Resources],
    env_vars: Optional[dict[str, str]],
    secrets: Optional[SecretRequest],
    depends_on: Optional[List[Environment]],
    description: Optional[str],
    interruptible: Optional[bool],
    kwargs: **kwargs,
) -> AppEnvironment

container_args()

def container_args(
    serialize_context: SerializationContext,
) -> List[str]

container_cmd()

def container_cmd(
    serialize_context: SerializationContext,
    parameter_overrides: list[Parameter] | None,
) -> List[str]

container_command()

def container_command(
    serialization_context: SerializationContext,
) -> list[str]

get_port()

def get_port()

on_shutdown()

def on_shutdown(
    fn: Callable[..., None],
) -> Callable[..., None]

Decorator to define the shutdown function for the app environment.

This function is called after the server function is called.

This decorated function can be a sync or async function, and accepts input parameters based on the Parameters defined in the AppEnvironment definition.

on_startup()

def on_startup(
    fn: Callable[..., None],
) -> Callable[..., None]

Decorator to define the startup function for the app environment.

This function is called before the server function is called.

The decorated function can be a sync or async function, and accepts input parameters based on the Parameters defined in the AppEnvironment definition.

server()

def server(
    fn: Callable[..., None],
) -> Callable[..., None]

Decorator to define the server function for the app environment.

This decorated function can be a sync or async function, and accepts input parameters based on the Parameters defined in the AppEnvironment definition.