From 8daead622078e2dd3d96e7a802db6bd07e635bd8 Mon Sep 17 00:00:00 2001 From: Steve Smtih Date: Mon, 5 Oct 2026 05:08:51 -0700 Subject: [PATCH] docs: clarify timeout-vs-retry behavior and retry headers for API Request Tool --- fern/tools/api-request/reliability.mdx | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/fern/tools/api-request/reliability.mdx b/fern/tools/api-request/reliability.mdx index b4dd5b1ed..c12acd3d8 100644 --- a/fern/tools/api-request/reliability.mdx +++ b/fern/tools/api-request/reliability.mdx @@ -168,7 +168,21 @@ curl --request POST \ }' ``` -Keep the retry limit small for voice calls. Every additional attempt can extend the silence or filler time before the assistant receives a final result. +Keep the retry limit small for voice calls. Every additional attempt can extend the silence or filler time before the assistant returns a final result. + +## Timeouts versus retries + +`excludedStatusCodes` and the "non-2xx responses are retryable" rule above both describe a request that reaches your endpoint and gets an HTTP response back. A request that never gets a response before `timeoutSeconds` elapses is a different failure mode, and whether that counts as a retryable attempt under `backoffPlan` is not yet documented here. + + +If your tool depends on exactly when a timed-out request retries, verify the behavior for your `backoffPlan` configuration against a non-production endpoint before relying on it, or confirm with [Vapi support](https://help.vapi.ai). + + + + +To see what Vapi actually sent and received on an attempt, including the non-sensitive request headers, open the delivery in [Webhook logs](/observability/logs/webhook-logs). Webhook logs record each delivery's request and response, but do not currently document whether a retry attempt carries different headers than the original request. + + ## Keep the caller informed