diff --git a/api/services/pipecat/pre_call_fetch.py b/api/services/pipecat/pre_call_fetch.py
index 7776111..8a2025b 100644
--- a/api/services/pipecat/pre_call_fetch.py
+++ b/api/services/pipecat/pre_call_fetch.py
@@ -15,6 +15,29 @@ from api.utils.credential_auth import build_auth_header
PRE_CALL_FETCH_TIMEOUT_SECONDS = 10
+def _extract_initial_context(response_data: Dict[str, Any]) -> Dict[str, Any]:
+ """Pull the context variables out of a pre-call fetch response.
+
+ The canonical key is ``initial_context``. The legacy ``dynamic_variables``
+ key is still accepted for backward compatibility, so existing endpoints
+ keep working; ``initial_context`` takes precedence when both are present.
+
+ Either key may appear at the top level or nested under ``call_inbound``:
+ {"call_inbound": {"initial_context": {...}}} | {"initial_context": {...}}
+ {"call_inbound": {"dynamic_variables": {...}}} | {"dynamic_variables": {...}}
+ """
+ container = response_data.get("call_inbound")
+ if not isinstance(container, dict):
+ container = response_data
+
+ for key in ("initial_context", "dynamic_variables"):
+ value = container.get(key)
+ if isinstance(value, dict):
+ return value
+
+ return {}
+
+
async def execute_pre_call_fetch(
*,
url: str,
@@ -77,24 +100,16 @@ async def execute_pre_call_fetch(
)
return {}
- # Extract dynamic_variables from Retell-compatible response
- # Supports: {call_inbound: {dynamic_variables: {...}}}
- # or: {dynamic_variables: {...}}
- dynamic_vars = {}
- call_inbound = response_data.get("call_inbound")
- if isinstance(call_inbound, dict):
- dynamic_vars = call_inbound.get("dynamic_variables", {})
- elif "dynamic_variables" in response_data:
- dynamic_vars = response_data["dynamic_variables"]
-
- if not isinstance(dynamic_vars, dict):
- dynamic_vars = {}
+ # Extract the variables to merge into initial_context. Prefers
+ # the canonical `initial_context` key, falling back to the
+ # legacy `dynamic_variables` key for backward compatibility.
+ initial_context_vars = _extract_initial_context(response_data)
logger.info(
f"Pre-call fetch: success ({response.status_code}), "
- f"dynamic_variables keys: {list(dynamic_vars.keys())}"
+ f"initial_context keys: {list(initial_context_vars.keys())}"
)
- return dynamic_vars
+ return initial_context_vars
else:
logger.warning(
f"Pre-call fetch: HTTP {response.status_code} - "
diff --git a/api/tests/test_pre_call_fetch.py b/api/tests/test_pre_call_fetch.py
new file mode 100644
index 0000000..8016da2
--- /dev/null
+++ b/api/tests/test_pre_call_fetch.py
@@ -0,0 +1,66 @@
+from api.services.pipecat.pre_call_fetch import _extract_initial_context
+
+
+class TestExtractInitialContext:
+ """Tests for _extract_initial_context, the pre-call fetch response parser."""
+
+ def test_initial_context_nested_under_call_inbound(self):
+ """The canonical `initial_context` key nested under `call_inbound`."""
+ response = {"call_inbound": {"initial_context": {"customer_name": "Jane"}}}
+ assert _extract_initial_context(response) == {"customer_name": "Jane"}
+
+ def test_initial_context_at_top_level(self):
+ """The canonical `initial_context` key at the top level."""
+ response = {"initial_context": {"customer_name": "Jane"}}
+ assert _extract_initial_context(response) == {"customer_name": "Jane"}
+
+ def test_legacy_dynamic_variables_nested(self):
+ """The legacy `dynamic_variables` key still works nested under `call_inbound`."""
+ response = {"call_inbound": {"dynamic_variables": {"customer_name": "Jane"}}}
+ assert _extract_initial_context(response) == {"customer_name": "Jane"}
+
+ def test_legacy_dynamic_variables_at_top_level(self):
+ """The legacy `dynamic_variables` key still works at the top level."""
+ response = {"dynamic_variables": {"customer_name": "Jane"}}
+ assert _extract_initial_context(response) == {"customer_name": "Jane"}
+
+ def test_initial_context_takes_precedence_over_legacy(self):
+ """When both keys are present, `initial_context` wins."""
+ response = {
+ "call_inbound": {
+ "initial_context": {"source": "new"},
+ "dynamic_variables": {"source": "legacy"},
+ }
+ }
+ assert _extract_initial_context(response) == {"source": "new"}
+
+ def test_falls_back_to_legacy_when_initial_context_not_a_dict(self):
+ """A non-dict `initial_context` falls back to `dynamic_variables`."""
+ response = {
+ "initial_context": None,
+ "dynamic_variables": {"customer_name": "Jane"},
+ }
+ assert _extract_initial_context(response) == {"customer_name": "Jane"}
+
+ def test_nested_values_preserved(self):
+ """Nested objects pass through untouched for dot-notation access."""
+ response = {
+ "call_inbound": {
+ "initial_context": {"customer": {"address": {"city": "LA"}}}
+ }
+ }
+ assert _extract_initial_context(response) == {
+ "customer": {"address": {"city": "LA"}}
+ }
+
+ def test_empty_when_no_known_keys(self):
+ """A response with neither key yields an empty dict."""
+ assert _extract_initial_context({"call_inbound": {"agent_id": 1}}) == {}
+
+ def test_empty_when_call_inbound_missing(self):
+ """No `call_inbound` and no top-level keys yields an empty dict."""
+ assert _extract_initial_context({}) == {}
+
+ def test_non_dict_vars_yield_empty(self):
+ """A non-dict value under a known key yields an empty dict."""
+ assert _extract_initial_context({"initial_context": "nope"}) == {}
diff --git a/docs/core-concepts/context-and-variables.mdx b/docs/core-concepts/context-and-variables.mdx
index bfd81b0..274689c 100644
--- a/docs/core-concepts/context-and-variables.mdx
+++ b/docs/core-concepts/context-and-variables.mdx
@@ -18,20 +18,10 @@ initial_context ──► Agent ──► gathered_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
-- **Dashboard** — set default template context variables on the agent, used when no external context is provided
-
-```json
-{
- "phone_number": "+14155550100",
- "initial_context": {
- "customer_name": "Jane Smith",
- "plan": "premium",
- "renewal_date": "April 1"
- }
-}
-```
+- **[API trigger](/voice-agent/api-trigger)** — pass it in the request body when calling `POST /public/agent/{uuid}` or `POST /telephony/initiate-call`
+- **[Campaign CSV](/core-concepts/campaigns)** — columns beyond `phone_number` automatically become `initial_context` fields for each contact's call
+- **[Pre-call data fetch](/voice-agent/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](/voice-agent/template-variables#using-template-variables-for-testing)** — 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
@@ -103,7 +93,7 @@ Data the agent collects *during* the call. You configure what to extract in the
-`gathered_context` is returned in the run record after the call completes and is available in [webhook payloads](/developer/webhooks) for downstream processing.
+`gathered_context` is returned in the run record after the call completes and is available in [webhook payloads](/developer/webhooks) for downstream processing. It is **not** available as a template variable in Agent prompts — prompts can only reference `initial_context` fields.
## Data flow example
diff --git a/docs/images/template-variables.png b/docs/images/template-variables.png
new file mode 100644
index 0000000..3594f9d
Binary files /dev/null and b/docs/images/template-variables.png differ
diff --git a/docs/voice-agent/api-trigger.mdx b/docs/voice-agent/api-trigger.mdx
index 1a464b6..e5168c7 100644
--- a/docs/voice-agent/api-trigger.mdx
+++ b/docs/voice-agent/api-trigger.mdx
@@ -118,7 +118,7 @@ For example, if your request includes:
}
```
-You can reference the user's name in your prompt as `{{initial_context.user.name}}`.
+You can reference the user's name in your agent prompt as `{{user.name}}` — in Agent prompts, `initial_context` fields are referenced directly by name (not prefixed with `initial_context.`). See [template variables](/voice-agent/template-variables) for the exact syntax in prompts versus webhook payloads.
See [Context & Variables](/core-concepts/context-and-variables) for more on how data flows through a call.
diff --git a/docs/voice-agent/pre-call-data-fetch.mdx b/docs/voice-agent/pre-call-data-fetch.mdx
index 53d1d9a..a793930 100644
--- a/docs/voice-agent/pre-call-data-fetch.mdx
+++ b/docs/voice-agent/pre-call-data-fetch.mdx
@@ -11,7 +11,7 @@ Pre-Call Data Fetch allows you to enrich the call context with external data bef
1. A call arrives (inbound) or is initiated (outbound).
2. Dograh sends a **POST** request to your configured endpoint with a standardized payload.
3. The caller hears a ring-back tone while waiting for the response.
-4. Your API responds with a JSON object containing `dynamic_variables`.
+4. Your API responds with a JSON object containing an `initial_context` object.
5. The variables are merged into the call's initial context.
6. The voice agent starts with full access to the fetched data via `{{variable_name}}` syntax.
@@ -50,12 +50,12 @@ The `Content-Type` header is set to `application/json`. If you configured a cred
## Expected Response Format
-Your API should return a **JSON object** with a `2xx` status code. The variables to inject into the call context should be placed inside the `dynamic_variables` key:
+Your API should return a **JSON object** with a `2xx` status code. The variables to inject into the call context should be placed inside the `initial_context` key:
```json
{
"call_inbound": {
- "dynamic_variables": {
+ "initial_context": {
"customer_name": "Jane Doe",
"account_status": "active",
"loyalty_tier": "gold",
@@ -65,34 +65,38 @@ Your API should return a **JSON object** with a `2xx` status code. The variables
}
```
-You can also place `dynamic_variables` at the top level:
+You can also place `initial_context` at the top level:
```json
{
- "dynamic_variables": {
+ "initial_context": {
"customer_name": "Jane Doe",
"account_status": "active"
}
}
```
+
+The legacy `dynamic_variables` key is still accepted as a drop-in alias for `initial_context`, so existing integrations keep working without any changes. Use `initial_context` for new integrations. If a response contains both keys, `initial_context` takes precedence.
+
+
After the response is received, you can reference these values anywhere template variables are supported:
- **Greeting**: `Hello {{customer_name}}, thank you for calling!`
- **Prompt**: `The customer is a {{loyalty_tier}} member with {{open_tickets}} open support tickets.`
-If the response is not a valid JSON object, does not contain `dynamic_variables`, or the request fails or times out, the call proceeds normally without the additional context. The pre-call fetch never blocks or fails a call.
+If the response is not a valid JSON object, does not contain `initial_context` (or the legacy `dynamic_variables`), or the request fails or times out, the call proceeds normally without the additional context. The pre-call fetch never blocks or fails a call.
## Nested Variables
-If your `dynamic_variables` contain nested objects, you can access them using dot notation:
+If your `initial_context` contains nested objects, you can access them using dot notation:
```json
{
"call_inbound": {
- "dynamic_variables": {
+ "initial_context": {
"customer": {
"name": "Jane Doe",
"address": {
@@ -153,7 +157,7 @@ app.post("/dograh/pre-call", async (req, res) => {
res.json({
call_inbound: {
- dynamic_variables: {
+ initial_context: {
customer_name: customer.name,
account_status: customer.status,
loyalty_tier: customer.tier,
diff --git a/docs/voice-agent/template-variables.mdx b/docs/voice-agent/template-variables.mdx
index 3db4a56..325317f 100644
--- a/docs/voice-agent/template-variables.mdx
+++ b/docs/voice-agent/template-variables.mdx
@@ -4,13 +4,23 @@ description: "You can use Template Variables in your prompts for your Agent node
---
### Template Rendering
-You can reference template variables which is passed as [`initial_context`](/core-concepts/context-and-variables#initial_context) either using the [API Trigger](/voice-agent/api-trigger) or when uploading a Sheet for a [campaign](/core-concepts/campaigns). You can also use any extracted variable as [`gathered_context`](/core-concepts/context-and-variables#gathered_context)
-The template rendering can take nested values.
+You reference template variables with `{{double_brace}}` syntax. The data comes from [`initial_context`](/core-concepts/context-and-variables#initial_context) — set via the [API Trigger](/voice-agent/api-trigger), a [campaign](/core-concepts/campaigns) sheet, or a [Pre-Call Data Fetch](/voice-agent/pre-call-data-fetch) that enriches the context when the call starts — and, in Webhook payloads only, from [`gathered_context`](/core-concepts/context-and-variables#gathered_context) (variables extracted during the call).
-Example: If the initial context is
+**The syntax depends on where you use it:**
-```
+| Where | `initial_context` | `gathered_context` |
+| --- | --- | --- |
+| Agent node prompts | `{{field_name}}` (referenced directly) | Not available |
+| Webhook Node payloads | `{{initial_context.field_name}}` | `{{gathered_context.field_name}}` |
+
+#### Agent node prompts
+
+In an Agent node prompt, reference each `initial_context` field **directly by name**. Nested values are supported with dot notation.
+
+Example: if the initial context is
+
+```json
{
"initial_context": {
"user": {
@@ -20,14 +30,26 @@ Example: If the initial context is
}
```
-You can write your prompt to access the user's name as below
+write your prompt to access the user's name as below:
-Prompt: `You are Alice, who is talking to {{initial_context.user.name}}.`
+Prompt: `You are Alice, who is talking to {{user.name}}.`
+
+
+Variables extracted during the call (`gathered_context`) are **not** available in Agent prompts — a prompt can only reference `initial_context` fields. To act on extracted data, send it to a [Webhook Node](/voice-agent/webhook).
+
+
+#### Webhook Node payloads
+
+When constructing a [Webhook Node](/voice-agent/webhook) payload, the context objects are nested under their names, so reference them with the `initial_context.` and `gathered_context.` prefixes:
+
+Payload value: `{{initial_context.user.name}}` or `{{gathered_context.call_disposition}}`
### Using Template Variables for Testing
Template variables defined in your workflow **Settings > Context Variables** are included in test calls (both web and phone) made from the workflow editor. This is useful for simulating data that would normally come from telephony or an API trigger.
+
+
For example, you can set `caller_number` and `called_number` as context variables to test [Pre-Call Data Fetch](/voice-agent/pre-call-data-fetch#testing-with-test-calls) without needing a real inbound call.