Tools

acrawl’s agent has 43 tools in six groups. The MCP server exposes 40 of them: every navigation, interaction, extraction and DevTools tool, the 7 script tools and run_goal. The 4 sub-agent tools are used inside the agent loop, so MCP clients reach them through run_goal.

Each tool’s exact parameters are in its JSON schema, which MCP clients receive when they connect. The tables below say what each one is for.

Navigation (7)

Tool	Purpose
navigate	Open a URL. HTTP first, browser when needed. Returns markdown, fit_markdown, text or html plus a page_map.
go_back	Browser back.
get_page_info	Cheap read of URL, title and ready state; optionally lists all tabs.
scroll	Scroll by pixels to trigger lazy loading.
switch_tab	Switch tabs by index.
wait	Wait for a selector state or a fixed time.
refresh	Reload, for example after adding intercept rules.

Interaction (8)

Tool	Purpose
click	Click by CSS selector, @eN ref or visible label.
click_at	Click viewport coordinates (canvas, maps, SVG).
fill_form	Fill fields by selector, name, ref or label; optional submit.
select_option	Pick from native or custom dropdowns, or list their options.
hover	Reveal tooltips and menus.
press_key	Send keys such as Enter, Escape or Tab.
set_device	Emulate a phone, tablet or desktop.
execute_js	Run JavaScript in the page and return the result.

Extraction (5)

Tool	Purpose
page_map	YAML accessibility tree with @eN refs, the main structural view.
read_content	Text by heading or selector, with pagination.
list_resources	Links, images and forms on the page.
screenshot	Full-page PNG.
save_file	Download a URL to the output folder.

DevTools and observation (12)

Tool	Purpose
list_network_activity / inspect_request	Requests with timing, state, initiator.
list_page_logs / inspect_log	Deduplicated console logs with stack traces.
list_websocket_activity / inspect_websocket	WebSocket connections and frames.
get_page_performance	TTFB, DOM timings, largest resources.
inspect_cookies	Cookies with security analysis.
inspect_storage	localStorage and sessionStorage.
measure_coverage	Used vs. loaded JS and CSS bytes.
audit_accessibility	axe-core WCAG audit.
intercept_network	Block or mock requests by URL pattern.

Sub-agents (4)

Tool	Purpose
fork	Start a child agent on a new tab with its own goal and step budget.
wait_for_subagents	Collect results from children.
subagent_status	Check children without blocking.
cancel_subagent	Stop a child.

Scripts (7)

Tool	Purpose
run_script	Run a deterministic script with no per-step LLM calls.
save_script / list_scripts / read_script	Store and reuse scripts.
wait_for_scripts / script_status / cancel_script	Track and control runs.

See Repeatable crawls with zero LLM calls.

Page formats

navigate takes a format that controls how much of the page comes back:

Format	What you get
fit_markdown	Recommended. Markdown with navigation, footers, ads, sidebars and other low-content blocks removed first. Typically 30 to 60% fewer tokens.
markdown	The whole page as Markdown.
text	Plain text.
html	The raw HTML.

fit_markdown drops elements whose class or id names them as navigation, footer, sidebar, ads, comments or sharing widgets, then scores what is left by text density, link density and tag, and keeps the content-heavy parts. Use markdown when the data you want lives in a sidebar or similar block. If pruning would leave nothing, the tool returns plain text instead.

What interaction tools return

Tools that change the page (click, click_at, fill_form, select_option, hover, press_key, scroll, go_back, switch_tab, set_device, refresh) return a page_state, so the agent sees the effect of its action without a separate call.

The first action on a URL returns the full accessibility tree, with a ref on every element the agent can use:

url: https://example.com/page
title: Page Title
page_map: |
  - main "" [ref=e1]:
    - navigation "Primary" [ref=e2]:
      - link "Docs" [ref=e3]:
    - heading "Platform" [level=1] [ref=e4]:
    - button "Get Started" [ref=e5]:

Later actions on the same page return only what changed, which keeps long sessions cheap:

url: https://example.com/page
title: Page Title
changed: true
changes: |
  + [ref=e5] added:
    - dialog "Confirm" [ref=e5]:
      - button "OK" [ref=e6]:
      - button "Cancel" [ref=e7]:
  ~ button "Submit" [ref=e2]: [] → [disabled]

If nothing changed, the result is just changed: false. When the changes are too large to diff usefully, the full tree comes back instead.