# Glossary of web automation

What the terms mean, how they work, and the code that uses them.

- [API discovery](/glossary/api-discovery): Finding the JSON requests a website makes behind its pages, so data can be read from them instead of from the screen.
- [Await input](/glossary/await-input): A step that pauses a job until you, a teammate or your own system supplies a value the program cannot know in advance, such as a one-time code.
- [Browser session](/glossary/browser-session): A saved, named login state (cookies and storage) that jobs reuse so they do not log in every time.
- [Canary run](/glossary/canary-run): A scheduled test run of a program that checks it still works on the live site before your real jobs find out it does not.
- [Captcha policy](/glossary/captcha-policy): What a program does when a site asks it to prove it is human: pause and wait for you, solve it, or fail.
- [Change detection](/glossary/change-detection): Running a program on a schedule and being told only when the fields you care about change.
- [Checkpoint](/glossary/checkpoint): A named point in a program that a job can restart from, so work already done is not done again.
- [Drift](/glossary/drift): The slow change of a website away from what a program was written against, until a step or a field stops matching.
- [Dry run](/glossary/dry-run): Running a program without carrying out its side effects, to see that it reaches them and would do the right thing.
- [Extract schema](/glossary/extract-schema): The description of the data a program returns: each field, where it is on the page, its type and the rules it must meet.
- [Headless browser](/glossary/headless-browser): A web browser that runs without a window, driven by a program instead of a person.
- [Hosted resolve page](/glossary/hosted-resolve-page): A page Kaabist hosts where you, a teammate or your customer can answer what a paused job is waiting for, with no Kaabist account or integration.
- [Idempotency key](/glossary/idempotency-key): A value sent with a request so that sending it again does not do the work again.
- [Landmark](/glossary/landmark): A named condition that says where a program is, such as being on the login page or being logged in.
- [Locator candidates](/glossary/locator-candidates): An ordered list of ways to find the same element, tried in turn until one matches exactly one element.
- [MCP (Model Context Protocol)](/glossary/mcp): An open protocol that lets AI applications such as coding agents call tools provided by other services.
- [Needs attention](/glossary/needs-attention): The state of a job that stopped because something got in the way that you need to decide on, kept so it can continue rather than fail.
- [Network capture](/glossary/network-capture): Reading the JSON a page receives from its own server while it loads, instead of reading what it draws.
- [Obstacle](/glossary/obstacle): Anything that covers the page a program wants to use: a cookie banner, a newsletter dialog, a product tour, a chat bubble.
- [Pagination](/glossary/pagination): Reading a list that is split across pages, by following the next link until there is none or a limit is reached.
- [Pick sample](/glossary/pick-sample): The value a field had when it was picked on the page, kept with the field as a permanent test.
- [Program](/glossary/program): A versioned JSON definition of a web automation: its inputs, steps, extraction and policies.
- [Program alias](/glossary/program-alias): A name such as production that points at one version of a program and can be moved without changing the code that runs it.
- [Proposal](/glossary/proposal): A suggested change to a program, such as a repaired locator, that waits for you to approve it before it becomes a new version.
- [Self-healing locator](/glossary/self-healing-locator): A way of finding an element on a page that survives when the page changes, by trying several candidates and repairing itself when all of them miss.
- [Session probe](/glossary/session-probe): A quick check, before a job starts, that a saved login is still valid.
- [Side-effect fence](/glossary/side-effect-fence): A guard around a step that changes something in the world, such as submitting a form or paying, so it is never done twice.
- [Takeover](/glossary/takeover): You or a teammate stepping into a paused job's live browser to do the one thing the program could not, then handing it back.
- [Tier ladder](/glossary/tier-ladder): The order in which Kaabist tries ways of loading a page: plain HTTP first, then a browser, then a stealth browser, stopping at the cap you set.
- [Webhook signature](/glossary/webhook-signature): A header that proves a webhook came from the service that claims to have sent it and was not changed on the way.