Context & Variables

Menace Voice has a simple data model for passing information through a call. Understanding it is key to building agents that feel personalised and to extracting useful results after a call.

The three context objects#

initial_context ──► Agent ──► gathered_context                       │                 [template variables](/voice-agent/template-variables)                 (used in prompts)

initial_context#

Data available to the agent before the call starts — the contact's name, account details, appointment information, anything the agent should know upfront. It can be set from several places:

• API trigger — pass it in the request body when calling POST /public/agent/{uuid} or POST /telephony/initiate-call
• Campaign CSV — columns beyond phone_number automatically become initial_context fields for each contact's call
• Pre-call data fetch — enrich the context with data from your CRM or ERP via an HTTP call as the call starts, before the agent speaks
• Agent Settings — set template context variables on the agent for testing; they're included in test calls from the workflow editor and ignored on production calls

Template variables#

Values from initial_context are available in your agent's prompt using {{double_brace}} syntax.

You are calling {{customer_name}} about their {{plan}} plan,which renews on {{renewal_date}}. Be friendly and confirmwhether they'd like to continue.

When the call starts, Menace Voice substitutes the values before sending the prompt to the LLM — so the agent speaks naturally as if it already knows the contact.

Fallback values#

If a variable might be missing or empty, use a pipe (|) to provide a default value:

Hello {{customer_name | there}}, we're calling about your {{plan | current}} plan.

When customer_name is not set, the agent will say "Hello there" instead of leaving a blank. The syntax is:

{{variable_name | fallback_value}}

If the variable is present and non-empty, the fallback is ignored and the actual value is used.

Default variables#

Built-in variables for current time and weekday, available in any prompt without setting up initial_context.

Replace <TIMEZONE> with an IANA timezone name such as Asia/Kolkata, America/New_York, or Europe/London.

Today is {{current_weekday}} and the current time is {{current_time_America/New_York}}.

Telephony variables#

For telephony calls (inbound and outbound), Menace Voice automatically adds these variables to initial_context:

For inbound calls, caller_number is the customer's number and called_number is your Menace Voice number. For outbound calls, it's the reverse — caller_number is your Menace Voice number and called_number is the customer's number.

You are speaking with the caller at {{caller_number}}.

gathered_context#

Data the agent extracts during the call — the opposite direction of initial_context. Use it to turn a conversation into structured data: what the customer wants, whether they confirmed something, a value they gave you out loud.

How it gets populated#

Turn on extraction on an Agent or End Call node and define one or more variables to extract. Each variable has:

When the conversation reaches that node, the LLM reads the transcript so far and fills in each variable based on its prompt. If a value can't be determined from the conversation, the variable is left empty rather than guessed — leave the prompt specific enough that the LLM knows exactly what counts as a match.

You can add extraction to more than one node. Each node's extracted variables are merged into the same gathered_context object as the call progresses, keyed by name — reuse a name at a later node if you want to overwrite an earlier value.

How to reference it downstream#

gathered_context is not available in Agent prompts — a prompt can only reference initial_context fields, because extraction typically happens after the conversation that would use it. To act on extracted data, send it out via a node instead:

{  "customer": "{{initial_context.customer_name}}",  "resolution": "{{gathered_context.resolution}}",  "callback_requested": "{{gathered_context.wants_callback}}"}

See Webhook Payloads for the full list of variables available alongside gathered_context in a payload template.

Data flow example#

Where variables are available#