Inbound Runtime Variables

When an inbound call is bridged to an agent, Callaro passes a set of runtime_vars to the voice runtime in addition to the usual variables. Your prompt can branch on these to greet the caller appropriately, acknowledge the campaign they’re returning to, or skip the introduction entirely. These variables are only present on inbound calls. Outbound prompts continue to use existing campaign/contact variables.

Variables

Key	Type	Description
`direction`	string	Always `"inbound"` for inbound calls.
`routing_reason`	string	Which layer of smart routing matched. One of `active_campaign`, `retry_pending`, `active_followup`, `last_outbound`, `did_fallback`, `no_active_match`.
`routing_layer`	string	Same as `routing_reason` but stable across renames; safe to switch on.
`inbound_routing_decision_id`	integer	DB id for the persisted decision trace; useful for support tickets.
`contact_id`	integer or null	Matched contact, if found.
`campaign_id`	integer or null	Matched `bulk_call_campaign_id` (when `routing_reason` is `active_campaign` or `retry_pending`).
`task_id`	integer or null	Matched `bulk_call_task_id` (when applicable). The task is closed as `contacted_inbound` before the agent picks up.
`follow_up_id`	integer or null	Matched `follow_up_id` (when `routing_reason` is `active_followup`). The follow-up is closed as `contacted_inbound` before the agent picks up.

The full list of canonical contact variables (e.g. contact.first_name, contact.metadata.*) is also resolved when a contact is matched.

Sample prompt branches

You can branch greetings and intent based on routing_reason. Pseudocode for the agent prompt’s opening lines:

{{#if routing_reason == "active_campaign"}}
Hi {{contact.first_name}}, thanks for calling back about
{{campaign.name}} — I was just trying to reach you.
{{else if routing_reason == "retry_pending"}}
Hi {{contact.first_name}}, perfect timing — I had a follow-up
scheduled for you on {{campaign.name}}.
{{else if routing_reason == "active_followup"}}
Hi {{contact.first_name}}, thanks for calling back —
I had a follow-up note for our last conversation.
{{else if routing_reason == "last_outbound"}}
Hi {{contact.first_name}}, thanks for getting back to me.
{{else}}
Hi, you've reached {{agent.name}}. How can I help?
{{/if}}

For non-conversational logic (tools, branches), prefer routing_layer since the value is stable across product renames.

Tips

The task_id and follow_up_id are already closed by the time the agent answers. Do not call task-completion tools again — instead, use the IDs to look up history when you need it.
direction == "inbound" is the easiest gate to keep inbound-only language out of outbound prompts.
For DID fallback (routing_reason == "did_fallback"), most inbound-specific variables are null. Treat it like a cold inbound call.
If you see routing_reason == "no_active_match", smart routing decided no agent was eligible; the call was bridged to the DID’s agent (or unknown agent) anyway. This is rare and usually indicates an agent went inactive between the inbound webhook and the bridge.

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Inbound runtime vars

Inbound Runtime Variables

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Sample prompt branches

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