> ## Documentation Index
> Fetch the complete documentation index at: https://docs.expectedparrot.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Survey messages

> Use SurveyMessage to add display-only, routable pages such as introductions, consent text, transitions, eligibility notices, and completion messages to an EDSL Survey.

`SurveyMessage` adds a page of information to a survey without asking the respondent—or a language model—to provide an answer. It behaves like a question in the survey flow: it has a `question_name`, occupies a normal survey position, and can be the source or destination of a routing rule.

Use it for introductions, consent or privacy information, section transitions, eligibility notices, and thank-you pages.

## Basic usage

```python theme={null}
from edsl import QuestionFreeText, Survey, SurveyMessage

welcome = SurveyMessage(
    question_name="welcome",
    question_text="Welcome. This survey takes about two minutes.",
)

feedback = QuestionFreeText(
    question_name="feedback",
    question_text="What could we improve?",
)

thanks = SurveyMessage(
    question_name="thanks",
    question_text="Thank you for your feedback.",
)

survey = Survey([welcome, feedback, thanks])
```

An interactive survey client should display the message and offer a **Continue** action (or **Finish** when it is the last node). `SurveyMessage` does not render an input control.

## Routing to a message

Because a message is a normal survey node, rules can route respondents to it by name. This example sends ineligible respondents to a terminal message while eligible respondents continue to a follow-up question:

```python theme={null}
from edsl import EndOfSurvey, QuestionFreeText, QuestionYesNo, Survey, SurveyMessage

eligible = QuestionYesNo(
    question_name="eligible",
    question_text="Are you at least 18 years old?",
)

follow_up = QuestionFreeText(
    question_name="experience",
    question_text="Tell us about your experience.",
)

ineligible = SurveyMessage(
    question_name="ineligible",
    question_text="You are not eligible for this survey. Thank you for your time.",
)

survey = Survey([eligible, follow_up, ineligible])
survey.add_rule(
    "eligible",
    "{{ eligible.answer }} == 'No'",
    next_question="ineligible",
)
survey.add_rule("experience", "True", next_question=EndOfSurvey)
```

The message participates in ordinary navigation, including back navigation and resume behavior in clients that support those features.

## Running with language models

When an EDSL job reaches a `SurveyMessage`, EDSL records a deterministic response and continues without calling the language model:

```python theme={null}
results = survey.run()
results.select("answer.ineligible")
```

If the message was visited, its recorded answer is `"continued"`. If routing skipped it, it has no response. The deterministic value makes the visited path observable in `Results` without spending inference tokens on display-only content.

## `SurveyMessage` versus `Instruction`

| Use                                        | `SurveyMessage`       | `Instruction` |
| ------------------------------------------ | --------------------- | ------------- |
| Show a standalone page to a respondent     | Yes                   | No            |
| Route to or from the item by question name | Yes                   | No            |
| Record that the item was visited           | Yes, as `"continued"` | No            |
| Supply context to later model questions    | No                    | Yes           |

Use `Instruction` when text should become model context for later questions. Use `SurveyMessage` when the text is itself a visible step in the survey experience.

## Human survey clients

`SurveyMessage` serializes with `question_type="survey_message"` and has an empty Humanize schema because it accepts no respondent input. A survey builder or Humanize client must explicitly support this question type by rendering the message and submitting the deterministic continuation action. Check client compatibility before deploying a human survey that contains messages.