Module webhook 

The webhook side of push delivery: which headers carry the notification token, how a receiver reads it, and how a webhook URL is named in logs.

Why two token headers

The specification does not name the header. §4.3.3’s request example shows only Authorization and Content-Type, and a2a.proto describes TaskPushNotificationConfig.token as “a token unique for this task or session” without saying how it travels. The two reference SDKs chose differently:

• a2a-sdk (Python) 1.1.5, server/tasks/base_push_notification_sender.py: headers = {'X-A2A-Notification-Token': push_info.token}
• a2a-go v2.5.0, a2asrv/push/sender.go: var tokenHeader = http.CanonicalHeaderKey("A2A-Notification-Token")

A webhook written against one never sees the other’s token, so HttpPushSender sends both — the same value twice, which costs one header line and cannot confuse a receiver that reads either — and notification_token accepts both.

Constants

NOTIFICATION_TOKEN_HEADER

The X-A2A-Notification-Token spelling, which a2a-sdk (Python) sends and reads.

NOTIFICATION_TOKEN_HEADER_UNPREFIXED

The A2A-Notification-Token spelling, which a2a-go sends and reads.

Functions

notification_token

Reads the push notification token from a webhook request’s headers, under either spelling.