You name the pages to watch. Each morning they are read, and you get an email when one moves.
For a shop owner or marketer who watches rival prices or pages.
Firecrawl
ResendStart the page and price watch blueprint on Typestate
Asked you for the address your emails come from.
Started Page and price watch: 2 record types, 4 web endpoints.
5 actions are compiling.
Deployed to Sandbox. Try it at your Sandbox address.
Each step has 3 parts: who starts it, how it reaches your backend, and the action that answers.
The rule you will want to change first
A page counts as changed when its text differs from the last reading. Name a part, such as .price, to watch only the price.
It lives in the action Check a Page. Tell your agent how you want it instead: one sentence changes, and you read the change before it goes Live.
The map shows the records it keeps, the actions it runs and the services it calls.
What it keeps
What it does
What it reaches
One page you watch, with its last reading.
Each person sees and changes only the pages they watch.
Each time a page moved, with the text before and after.
Each person sees only the changes of their own pages.
Open an action to read its steps: each sentence, with the calls that do it under it.
From the webPOST /pages
Nametext, needed
URLtext, needed
Parttext, optional
When the given address does not start with https://, refuse with "The address must start with https://".
When not (input.url starts with "https://")
Refuse "The address must start with https://"
Count the Pages of the signed-in person.When there are 50 or more, refuse with "You watch 50 pages already".
Each page is one Firecrawl call a day, so the count keeps the bill small.
pages is
Count Pages where
person_id is caller.id
When pages is at least 50
Refuse "You watch 50 pages already"
Create a Page with person_id set to the signed-in person, email set to the address they signed in with, the given name, address and part, and active set to yes.
Add a Page
set active to true
set email to caller.email
set name to input.name
set part to input.part
set person_id to caller.id
set url to input.url
Answer with that Page's id.
Answer
id is page.id
From the webPOST /pages/check
Page IDtext, needed
Find the Page whose id is the given page id.When none matches, refuse with "No such page".
page is
Find the first Page where
id is input.page_id
when none refuse "No such page"
Ask Firecrawl to read that Page's address now as Markdown, never from a saved copy, only its main content, and only the part the Page names when it names one.If that fails, refuse with "The page could not be read".
read is
Ask Firecrawl to Scrape Page
formats is a list of 1:
"markdown"
includeTags is
when
page.part holds a value
then the list of the page's part
otherwise an empty list
maxAge is 0
onlyMainContent is true
url is page.url
when it fails
Refuse "The page could not be read"
new_text is
take read.data.markdown
or, when that gives nothing, take ""
then cut the spaces at its ends
The page changed when that Page has a last text and the new text is not the same.
changed is
page.last_text holds a value
and page.last_text is not new_text
When the page changed, create a Change with person_id set to that Page's person, page_id and page_name set to that Page's id and name, before set to its last text, and after set to the new text.
When changed
Add a Change
set after to new_text
set before to page.last_text
set page_id to page.id
set page_name to page.name
set person_id to page.person_id
When the page changed, email that Page's address with the subject "A page you watch changed", naming the page and its address.
When changed
Send an email
to page.email
template "Check a Page Email"
name page.name
url page.url
Change that Page's last text to the new text and its last reading to now.
Change the Page where
id is page.id
set last_read_at to now
set last_text to new_text
Answer whether the page changed.
Answer
changed is changed
A timer, every day at 07:00, Berlin time
Nothing. It needs no input.
Find up to 50 Pages of the signed-in person whose active is yes.
pages is
Find Pages where
active is true
person_id is caller.id
For each of them, run Check a Page in the background with its id, as the person who made this request.
For each page in pages, at most 50
Run Check a Page in the background
page_id is page.id
as the person who asked
From the webGET /changes
Nothing. It needs no input.
Find up to 50 Changes of the signed-in person, newest first.
found is
Find Changes where
person_id is caller.id
sorted by created_at, highest first
Answer with each Change's page id, page name, text before, text after and the time it was seen.
Answer
changes is
each change of found as
after is change.after
before is change.before
page_id is change.page_id
page_name is change.page_name
seen_at is change.created_at
From the webPOST /pages/stop
Page IDtext, needed
Find the Page whose id is the given page id.When none matches, refuse with "No such page".
page is
Find the first Page where
id is input.page_id
when none refuse "No such page"
Change that Page's active to no.
Change the Page where
id is page.id
set active to false
Answer with that Page's id.
Answer
id is page.id
People sign up and sign in with an email address and a password, or with a provider you add, such as Google.
| What it does | Who may call | Address |
|---|---|---|
| You name a page to watch. | a signed-in person | POST /pages |
| You read a page now, without waiting for the morning. | a signed-in person | POST /pages/check |
| You read what moved. | a signed-in person | GET /changes |
| You stop watching a page. | a signed-in person | POST /pages/stop |
Typestate is the backend. Paste this brief into Lovable, v0, Claude Code or the tool that builds your pages.
Starting from this blueprint does not count against the action changes of your plan. The Free plan runs it on Sandbox. Live needs a paid plan.
Start the page and price watch blueprint on TypestateChoose a planReaders subscribe for free or pay monthly. Paid issues go to paying readers first, and open to everyone after 30 days.
7 actionsEach sale and delivery moves the stock, and the owner gets one email when a product runs low.
5 actionsPeople join a waiting list from your page, and each friend they bring moves them up.
4 actions