System Variables

System variables are predefined, read-only variables that are automatically managed by the indigo.ai platform. Unlike custom variables, they cannot be edited using blocks like Set Value or Capture. Instead, they provide real-time context about the user, session, platform environment, and conversation history, allowing you to create more intelligent and personalized experiences.

They are always identified by the prefix $, e.g. $project_id.

System variables help your AI Agents:

• Identify users, channels, and environments

• React based on the time and date

• Track conversation flow and user behavior

• Dynamically adapt logic based on platform state

• Access content retrieved via document search (RAG) or current workflow status

Use them to build smarter flows, trigger conditional logic, and create more relevant, responsive interactions.

Categories and Variables

🌐 Platform & Session Context

• $install_url – The URL where the widget is installed (useful for multi-site setups).

• $project_id – Your workspace's unique identifier.

• $env – Returns TEST or PRODUCTION, depending on where the assistant is running.

• $lang – Language code set for the workspace (e.g., en, it).

• $detected_language – Language detected from the user's latest message.

👤 User Identification

• $user_id – Session-based ID for the current user.

• $user_ref – Persistent user identifier that remains consistent across sessions (ideal for CRM matching).

🕒 Time & Date

• $timestamp – Current time in seconds (Unix timestamp).

• $date – Full timestamp in your workspace’s timezone (YYYY-MM-DD hh:mm:ss).

• $date_year, $date_month, $date_weekday, $date_hour – Individual date components useful for business logic (e.g., trigger actions only during working hours).

🧠 Conversation & Context

• $last_user_message – Content of the user's most recent message or button click.

• $intent – Last recognized intent label.

• $message_id – ID of the most recent inbound message (for tracking or referencing externally).

• $conversation – Full list of the last 100 messages in the current chat (in JSON format).

  jsonCopiaModifica[
    {"sender": "bot", "text": "..."},
    {"sender": "user", "text": "..."}
  ]

A “chat” refers to messages from the latest session, while a “conversation” spans all user interactions over time.

• $context_1 to $context_5 – Store the last 1 to 5 pairs of user and assistant messages in plain text. Ideal for use in prompts or as input for LLMs.

Behavior of the $last_user_message variable

The last_user_message variable has a specific behavior:

• It is aligned with other system variables by adding the $ prefix → $last_user_message.

• It updates automatically:

  • after each user message,

  • even after a capture block.

• It can be used in agents and prompts always with the latest consistent value.

Exception in the capture block

If a capture block collects exactly the value of $last_user_message:

• a dummy variable is used,

• its only purpose is to allow the capture block to work,

• the captured value is not used later in the flow.

📚 Content & Workflow State

• $documents – A list of documents retrieved from your knowledge base. Use this to:

  • Display matched sources

  • Trigger logic based on content relevance

  • Chain actions across workflows using retrieved data

• $current_workflow – Label of the currently executing workflow.

• $previous_workflow – Label of the workflow executed immediately prior to the current one.

✅ Utility

• $true – A constant that always returns true. Handy for testing or creating unconditional branches in Condition Blocks.

It is possible to create custom variables with the same name as a system variable, but:

• modifying them does not update the system variable

• using them is not linked to the corresponding system variable