Pipeline steps

A YAML pipeline passes the output of each action to the next. Uni-CLI currently has 113 built-in actions.

The total includes 58 registered pipeline actions.

It also includes 55 transport-native actions.

Basic shape

pipeline:
  - fetch:
      url: https://api.example.com/items
  - select: data.items
  - map:
      title: ${{ item.title }}
      url: ${{ item.url }}
  - limit: ${{ args.limit }}

HTTP and content

Action	Purpose
fetch	Request JSON or another structured HTTP response
fetch_text	Request raw text or HTML
parse_rss	Parse RSS or Atom
html_to_md	Convert HTML to Markdown
download	Save a remote file
oauth2-token	Request and store an OAuth 2 token
websocket	Exchange messages over WebSocket

- fetch:
    url: https://api.example.com/search
    method: GET
    params:
      q: ${{ args.query }}
    headers:
      Accept: application/json

fetch accepts JSON and fetch_text accepts bounded textual content. Both share validated redirects, response classification, and retry scheduling. retry counts total attempts. An upstream Retry-After value sets a minimum wait in seconds or HTTP-date form, and caller cancellation stops that wait. Interrupted successful read bodies use the remaining attempt budget. Accepted writes with interrupted bodies return operation_outcome_ambiguous for state reconciliation.

cache is a GET-only freshness ceiling in seconds. Request headers partition the stored representation and credentials. Response max-age and Age further constrain freshness. no-store, no-cache, private, and Vary: * disable reuse. Writes publish atomically. cache: 0 bypasses a stored response.

Transform data

Action	Purpose
select	Read a path from the current value
select-xml	Select data from XML
extract	Extract fields from HTML or DOM
map	Map each item to a new object
filter	Keep matching items
sort	Sort a list
limit	Keep the first N items
to_entries	Convert an object to key/value entries
split_text	Split text into parts
set	Store a named value
append	Add a value to a list
assert	Validate a result condition

- map:
    title: ${{ item.title }}
    author: ${{ item.by }}
- filter: item.title && !item.deleted
- sort:
    by: score
    order: desc
- limit: 10

Control flow

Action	Purpose
if	Run a branch when a condition matches
each	Run a child pipeline for each item
parallel	Run independent branches concurrently
rate_limit	Pace work for one domain or resource
wait	Wait for time or a target condition

- each:
    parallel: 4
    pipeline:
      - fetch:
          url: https://api.example.com/items/${{ item.id }}

Browser

Action	Purpose
navigate	Open a URL
evaluate	Run page JavaScript
click	Click a selected element
type	Enter text
press	Send a key
scroll	Scroll the page
snapshot	Read a page snapshot and refs
tap	Activate a ref
intercept	Capture matching browser requests

- navigate:
    url: https://example.com
- snapshot:
    interactive: true
- click:
    selector: "#sign-in"

Local and desktop orchestration

Action	Purpose
exec	Start an executable with an argv array
write_temp	Create a temporary file for a later action
compute_*	Route snapshot, input, screenshot, assertion, and session actions through compute

Common compute actions include compute_snapshot, compute_find, compute_click, compute_type, compute_press, compute_scroll, compute_screenshot, compute_assert, compute_session_start, compute_session_state, and compute_session_end.

- exec:
    command: ffprobe
    args: ["-v", "quiet", "-print_format", "json", ${{ args.file }}]
    parse: json
    timeout: 30000

Registered actions

The following names are registered actions.

append, assert, click, compute_apps, compute_assert, compute_cdp_attach,
compute_click, compute_drag, compute_evaluate, compute_find, compute_launch,
compute_observe, compute_point_click, compute_point_scroll, compute_press,
compute_screenshot, compute_scroll, compute_session_end,
compute_session_escalate, compute_session_start, compute_session_state,
compute_snapshot, compute_text, compute_type, compute_wait, compute_windows,
download, each, evaluate, exec, extract, fetch, fetch_text, filter,
html_to_md, if, intercept, limit, map, navigate, oauth2-token, parallel,
parse_rss, press, rate_limit, scroll, select, select-xml, set, snapshot,
sort, split_text, tap, to_entries, type, wait, websocket, write_temp

Transport-native actions

Transport adapters also expose macOS AX, Windows UIA, Linux AT-SPI, clipboard, application, and visual actions. The following names identify these actions.

applescript, ax_*, uia_*, atspi_*, clipboard_read, clipboard_write,
focus_window, launch_app, visual_*

These actions execute through the selected transport provider and its capability row. src/engine/step-surface.ts derives the complete live list from the registered step registry and transport handler tables.

Templates

The following expressions access common values.

Expression	Value
${{ args.name }}	Command argument
${{ item.field }}	Field on the current item
${{ index }}	Current list index
${{ env.NAME }}	Environment value

Step schemas live with their implementations under src/engine/steps/. Run npm run lint:adapters after editing a pipeline.