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Tutorial

Run your first study

1234Your first study

2 clips

How a study fits together

A Carrier study has four parts: chamberlines, chambers, segments and the cast. This tutorial shows them in one small study, then two participants take it.

  • Basics
4 min read Start →
3 clips

Find your way around the builder

Start a new experiment from the dashboard, learn the function of each area of the builder, and save the experiment with Deploy.

  • Basics
4 min read Start →
3 clips

Add a chamberline

Add a second path through the study, give a chamberline a name, copy a chamberline, and delete a chamberline.

  • Basics
  • Conditions & assignment
3 min read Start →
3 clips

Add a chamber

Name a chamber, add a second chamber, change the order of chambers, and remove a chamber. Also learn how a chamber sets the groups of participants.

  • Basics
3 min read Start →
3 clips

Drag a segment into a chamber

Add segments from the library, put them in order, remove a segment, and open the settings of a segment. The settings of a chat include text, audio or video.

  • Basics
  • Instruction
  • +1
3 min read Start →
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How a segment ends and the next begins

Set the maximum and minimum time of a segment, and learn the four transition modes: Auto, Manual, Sync and Host.

  • Basics
4 min read Start →
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Add a human participant to the room

Add seats for people to a chamber. Each human slot is one participant. Matching waits for the same number of participants as there are slots.

  • Basics
  • Communicator
  • +1
3 min read Start →
2 clips

Add an agent to the room

Make an agent, give it the name that participants see, and put it in a chamber with the participants.

  • Basics
  • Communicator
  • +2
3 min read Start →
6 clips

Your first study in ten minutes

Make a new experiment with a welcome page, a chat for pairs and a closing page. Check it, save it, open it and share it. Then two participants take it.

  • Basics
  • Testing & piloting
8 min read Start →
5 clips

A scripted confederate

A scripted agent says only your lines. Make a timed greeting, a keyword reply with a follow-up, and a line at a number of messages.

  • Scripted agents
  • Communicator
  • +1
6 min read Start →
4 clips

An AI partner in a chat

Make an agent reply with an AI model. Set its provider, model, prompt and reply timing. Add the experiment's API key and change the provider.

  • AI agents
  • Communicator
  • +1
6 min read Start →
4 clips

Slides: a briefing deck

Give participants information with a short deck. Make the slides, decide if participants can go back, and see the path of each participant.

  • Slide
  • Embedded layout
5 min read Start →
3 clips

Instruction pages that use answers

Write an instruction page in Markdown, set the label of its button, and show an earlier answer in the text with a variable.

  • Instruction
  • Variables
4 min read Start →
3 clips

Rank, and see the group's ranking

Each person ranks the options on their screen. The average ranking of the group shows while they rank. Then the group discusses it.

  • Rank
  • Chat
  • +1
5 min read Start →
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Watch a clip before you discuss

Show a video or audio clip: set its address, a poster frame and captions, and if participants can pause it. Know what Carrier records and what it does not record.

  • Media
4 min read Start →
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Wait together: timers and synchronised starts

A timed pause with a countdown before the discussion, then a page that waits until all persons in the group are ready.

  • Timer
4 min read Start →
3 clips

Attention checks

A question with a correct answer that the server checks. What a wrong answer does: retry, continue or end the study. Where Carrier records each attempt.

  • Attention check
  • Completion & redirects
5 min read Start →
4 clips

Standalone and embedded segments

A segment either fills the screen or runs in the chat before it. Learn how to embed a segment, and how the chat knows when to end.

  • Embedded layout
  • Chat
  • +1
7 min read Start →
3 clips

Cards in the chat: triggers and endings

When an embedded card appears, how it looks, what it does when it is complete, and how one card follows another.

  • Embedded layout
  • Chat
  • +1
7 min read Start →
2 clips

The split screen: reading beside the chat

An embedded segment in the Split layout fills the main area, and the chat moves to the side. Use it for a brief that participants read during the discussion.

  • Embedded layout
  • PDF
  • +1
5 min read Start →
4 clips

A mediated group discussion

Carrier matches three participants. One participant is the mediator, and two participants discuss a policy question.

  • Mediator
  • Group matching
  • +1
12 min read Start →
6 clips

Control group composition with a survey answer

Two conditions of discussions with six persons. One chamberline makes groups of 4:2 and the other makes groups of 3:3, from the answer to "Nuclear power is safe."

  • Group matching
  • Survey
  • +2
12 min read Start →
3 clips

A hidden processor beside a human

An LLM reviews a message before the participant sends it, and suggests a revision. The participant makes the decision.

  • Processor
  • AI agents
  • +1
9 min read Start →
4 clips

Read an open answer with AI processing

An AI-processed variable reads the free-text answer of a participant. The next page shows the result.

  • Variables
  • Process
  • +1
6 min read Start →
5 clips

Update a belief map live with AI processing

A belief map next to a chat. An AI-processed variable reads the map and the conversation every 15 seconds and updates the map.

  • Variables
  • AI agents
  • +3
12 min read Start →
2 clips

Add a feed to a chamber

Add a social media feed to a study. Drag the Social segment in, open its Feed Builder, and learn its parts.

  • Social
4 min read Start →
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Accounts: who posts

The accounts in a feed: how to add, name and remove an account, and the difference between a crowd account and an agent account.

  • Social
3 min read Start →
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Write a post

A post from one of the feed's accounts: its caption, image, time label and likes. Also how to remove a post.

  • Social
4 min read Start →
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Feed settings

The feed actions that participants can do: like, reply, share and save. Also the start state of comments, the participant's name and the post order.

  • Social
3 min read Start →
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The Instagram-like layout

Posts that show the photo first, a double-tap like, and one level of replies. Also what the feed records when participants use them.

  • Social
3 min read Start →
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The Facebook-like layout

Posts that show the caption first, with a bar of labelled Like, Comment, Share and Save buttons. Also how to change a feed to this layout, and what the feed records.

  • Social
3 min read Start →
3 clips

The Reddit-like layout

Forum threads: post titles, communities and scores, text posts and link posts, up and down votes on posts and comments, and nested replies.

  • Social
  • Data & export
5 min read Start →
2 clips

Bind an agent to an account

Make an agent reply to participants' comments as a feed account. Bind the agent, select its posts, and give its replies a human speed.

  • Social
  • AI agents
4 min read Start →
7 clips

Build a social media study with simulated accounts

Make a feed in which simulated accounts reply to participants in persona. Add images, import a CSV of posts, bind agents to accounts, and do a test run.

  • Social
  • AI agents
15 min read Start →
3 clips

Posts that arrive over time

Schedule posts to appear during the session behind a "new posts" pill. Delay agent replies so that they look like replies from people, not from bots.

  • Social
6 min read Start →
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What the feed records

The comments, likes, follows, votes and timestamped actions of a participant on a feed. You can use them as variables in later segments, and they are in the export.

  • Social
  • Variables
  • +1
5 min read Start →
3 clips

Personalised feeds and personas

Captions that show the participant's own survey answer, and agent accounts that read the answers before they reply.

  • Social
  • Variables
  • +2
6 min read Start →
3 clips

A static feed with scripted comment threads

Write all comments before the study: who writes what, who replies to whom, and when a reply shows. No live agents are necessary.

  • Social
6 min read Start →
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Build a shopping study with a budget and reviews

Make a mock store from an empty chamber: a catalogue and reviews from the starter kit, a budget, a shuffled grid, and a test purchase. Participants must check out to continue.

  • Shop
12 min read Start →
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Add an AI shop assistant and buyers who answer questions

Connect chamber agents to a store: a buyer who answers product questions after a delay, and a shop assistant who knows the cart.

  • Shop
  • AI agents
9 min read Start →
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Change prices, stock and reviews while a shop runs

Schedule a price increase and a sell-out on the segment clock. Decide if they skip shoppers who have the product in the cart. Change a running shop for one shopper from the dashboard.

  • Shop
9 min read Start →
5 clips

Variables, from the start

What a variable is, and three variables to start with: a constant, a random pick for each participant, and a score from answers. Each one shows in a page and in the export.

  • Variables
7 min read Start →
5 clips

Two conditions, counterbalanced

A second chamberline, assignment with a counterbalance variable, and conditions that stay separate.

  • Conditions & assignment
  • Variables
  • +1
8 min read Start →
5 clips

Balance a baseline attitude across conditions

A pre-survey rating puts each participant in a band. Each band has its own line, so the conditions stay equal in each band and in total.

  • Conditions & assignment
  • Variables
  • +1
8 min read Start →
3 clips

Match participants on a survey answer

An answer from an intake survey becomes a variable that pairs a participant who agrees with a participant who disagrees.

  • Group matching
  • Survey
  • +1
6 min read Start →
3 clips

Shared surveys around per-condition feeds

One pre-survey and one post-survey that all conditions share, with a different feed between them, and where the answers are in the export.

  • Global surveys
  • Conditions & assignment
  • +2
5 min read Start →
4 clips

Use the pre-survey as a consent form

Add a consent question to the global pre-survey, and a rule that ends the study for anyone who does not agree. Carrier records these runs as Declined Consent.

  • Global surveys
  • Completion & redirects
5 min read Start →
2 clips

Drop a jsPsych task into a session

An existing reaction-time task runs without changes in a task segment. Its results come back as variables.

  • Task
  • Variables
7 min read Start →
7 clips

Test, deploy and share a study

Check a study, try it without recording data, connect it to a recruitment platform, deploy it, open it to participants and monitor it.

  • Testing & piloting
10 min read Start →
4 clips

Piloting with your lab

Try a study with colleagues before real participants take part. Learn about testing mode, many test participants at the same time, test data, the export and Go live.

  • Testing & piloting
5 min read Start →
3 clips

Your data: what the export holds

The three export formats, the contents of the main sheets (Participants, Responses, Segment Submissions, Chat History), and how to join them on participantId.

  • Data & export
6 min read Start →
9 clips

Recruit participants through Prolific

Step by step: the study link that Prolific opens and the participant ID. Then a different Prolific completion code for each exit: finish, no partner found, failed attention check and screened out.

  • Recruitment
  • Completion & redirects
  • +2
12 min read Start →
5 clips

Build a study with an AI assistant

Connect an assistant such as Claude to Carrier (preview) and let it build a draft. Then examine the draft in the builder: History, and edits by you and the assistant at the same time. "Connect Claude Code or Codex to Carrier" and "Build a simple study with an assistant" show the setup and an example.

  • Basics
5 min read Start →
3 clips

Connect Claude Code or Codex to Carrier

Add Carrier as a server in Claude Code or Codex CLI, allow the connection, and make your first five requests. The last steps list the usual problems and show how to disconnect.

  • Basics
3 min read Start →
6 clips

Build a simple study with an assistant

Build Harbour pilot, a group-chat study with two conditions, in six requests to a connected assistant. After each request, check the draft in the builder. You do the last step: the completion redirect and Deploy.

  • Basics
  • Chat
  • +2
6 min read Start →
4 clips

Keep your work when the builder is offline

What the offline banner means, how to export your work as a file, what Deploy says while offline, and what to do when the connection returns.

  • Basics
3 min read Start →