Merge pull request #3 from warpdotdev/harry/app-3556-add-two-way-handshake-for-plugin-warp-versions

Add two way handshake for claude code plugin and Warp version

Author: harryalbert

plugins/warp/scripts/build-payload.sh

@@ -13,11 +13,28 @@
 # The function extracts common fields (session_id, cwd, project) from the
 # hook's stdin JSON (passed as $1), then merges any extra jq args you pass.
 
+# The current protocol version this plugin knows how to produce.
+PLUGIN_CURRENT_PROTOCOL_VERSION=1
+
+# Negotiate the protocol version with Warp.
+# Uses min(plugin_current, warp_declared), falling back to 1 if Warp doesn't advertise a version.
+negotiate_protocol_version() {
+    local warp_version="${WARP_CLI_AGENT_PROTOCOL_VERSION:-1}"
+    if [ "$warp_version" -lt "$PLUGIN_CURRENT_PROTOCOL_VERSION" ] 2>/dev/null; then
+        echo "$warp_version"
+    else
+        echo "$PLUGIN_CURRENT_PROTOCOL_VERSION"
+    fi
+}
+
 build_payload() {
     local input="$1"
     local event="$2"
     shift 2
 
+    local protocol_version
+    protocol_version=$(negotiate_protocol_version)
+
     # Extract common fields from the hook input
     local session_id cwd project
     session_id=$(echo "$input" | jq -r '.session_id // empty' 2>/dev/null)
@@ -30,11 +47,12 @@ build_payload() {
     # Build the payload: common fields + any extra args passed by the caller.
     # Extra args should be jq flag pairs like: --arg key "value" or --argjson key '{"a":1}'
     jq -nc \
+        --argjson v "$protocol_version" \
         --arg agent "claude" \
         --arg event "$event" \
         --arg session_id "$session_id" \
         --arg cwd "$cwd" \
         --arg project "$project" \
         "$@" \
-        '{v:1, agent:$agent, event:$event, session_id:$session_id, cwd:$cwd, project:$project} + $ARGS.named'
+        '{v:$v, agent:$agent, event:$event, session_id:$session_id, cwd:$cwd, project:$project} + $ARGS.named'
 }

plugins/warp/tests/test-hooks.sh

@@ -112,6 +112,36 @@ PAYLOAD=$(build_payload '{"session_id":"s1","cwd":"/tmp/proj"}' "stop" \
 assert_json_field "quotes in query preserved" "$PAYLOAD" ".query" 'what does "hello world" mean?'
 assert_json_field "parens in response preserved" "$PAYLOAD" ".response" 'It means greeting. Use: printf("hello")'
 
+echo ""
+echo "--- Protocol version negotiation ---"
+
+# Default: no env var set → falls back to plugin max (1)
+unset WARP_CLI_AGENT_PROTOCOL_VERSION
+PAYLOAD=$(build_payload '{"session_id":"s1","cwd":"/tmp"}' "stop")
+assert_json_field "defaults to v1 when env var absent" "$PAYLOAD" ".v" "1"
+
+# Warp declares v1 → use 1
+export WARP_CLI_AGENT_PROTOCOL_VERSION=1
+PAYLOAD=$(build_payload '{"session_id":"s1","cwd":"/tmp"}' "stop")
+assert_json_field "v1 when warp declares 1" "$PAYLOAD" ".v" "1"
+
+# Warp declares a higher version than the plugin knows → capped to plugin current
+export WARP_CLI_AGENT_PROTOCOL_VERSION=99
+PAYLOAD=$(build_payload '{"session_id":"s1","cwd":"/tmp"}' "stop")
+assert_json_field "capped to plugin current when warp is ahead" "$PAYLOAD" ".v" "1"
+
+# Warp declares a lower version than the plugin knows → use warp's version
+# (not testable with PLUGIN_MAX=1 since there's no v0, but we verify the min logic
+# by temporarily overriding the variable)
+PLUGIN_CURRENT_PROTOCOL_VERSION=5
+export WARP_CLI_AGENT_PROTOCOL_VERSION=3
+PAYLOAD=$(build_payload '{"session_id":"s1","cwd":"/tmp"}' "stop")
+assert_json_field "uses warp version when plugin is ahead" "$PAYLOAD" ".v" "3"
+PLUGIN_CURRENT_PROTOCOL_VERSION=1
+
+# Clean up
+unset WARP_CLI_AGENT_PROTOCOL_VERSION
+
 # --- Summary ---
 
 echo ""