From a90580c6d138056fecb380e47e1f42a8d22c233d Mon Sep 17 00:00:00 2001
From: Chris Huber <chubes@extrachill.com>
Date: Sun, 7 Jun 2026 22:23:29 -0400
Subject: [PATCH] Parse function_call-wrapped and bare JSON tool calls

The text tool-call fallback in WP_Agent_Provider_Turn_Result dropped tool
calls emitted as a bare JSON object (no <tool_call> tag or ```json fence)
and did not recognize the `{"type":"function_call","function_call":{...}}`
wrapper that some providers emit. Both shapes resulted in zero extracted
tool calls, so the model's tool call never executed.

Treat a trimmed message that is a single JSON object as a payload
candidate, and unwrap an inner `function_call` object before reading the
tool name and arguments. Adds smoke coverage for the wrapper shape.
---
 .../class-wp-agent-provider-turn-result.php     | 17 +++++++++++++++++
 tests/provider-turn-adapter-smoke.php           |  8 ++++++++
 2 files changed, 25 insertions(+)

diff --git a/src/Runtime/class-wp-agent-provider-turn-result.php b/src/Runtime/class-wp-agent-provider-turn-result.php
index 6674013..79aeea4 100644
--- a/src/Runtime/class-wp-agent-provider-turn-result.php
+++ b/src/Runtime/class-wp-agent-provider-turn-result.php
@@ -274,6 +274,16 @@ private static function extract_json_tool_calls( string $text ): array {
 			}
 		}
 
+		// Some providers emit a bare JSON tool-call object as the entire message
+		// with no fence or tag wrapper. Treat a trimmed text that is a single JSON
+		// object as a payload candidate so those calls are not dropped.
+		if ( empty( $payloads ) ) {
+			$trimmed = trim( $text );
+			if ( '' !== $trimmed && '{' === $trimmed[0] && '}' === substr( $trimmed, -1 ) ) {
+				$payloads[] = $trimmed;
+			}
+		}
+
 		return self::tool_calls_from_json_payloads( $payloads, 'json-tool-call' );
 	}
 
@@ -363,6 +373,13 @@ private static function tool_calls_from_json_payloads( array $payloads, string $
 					continue;
 				}
 
+				// Some providers wrap the call in a `function_call` object, often
+				// tagged with `{"type":"function_call", ...}`. Use that inner object
+				// as the call source so its name/arguments are read correctly.
+				if ( isset( $call['function_call'] ) && is_array( $call['function_call'] ) ) {
+					$call = $call['function_call'];
+				}
+
 				$function   = isset( $call['function'] ) && is_array( $call['function'] ) ? $call['function'] : array();
 				$raw_name   = $function['name'] ?? ( $call['name'] ?? '' );
 				$name       = is_string( $raw_name ) ? self::clean_tool_name( $raw_name ) : '';
diff --git a/tests/provider-turn-adapter-smoke.php b/tests/provider-turn-adapter-smoke.php
index de3a3d8..7597775 100644
--- a/tests/provider-turn-adapter-smoke.php
+++ b/tests/provider-turn-adapter-smoke.php
@@ -160,6 +160,14 @@ public function getText(): string {
 agents_api_smoke_assert_equals( 'json-1', $json_turn['tool_calls'][0]['id'] ?? '', 'fenced JSON fallback preserves id', $failures, $passes );
 agents_api_smoke_assert_equals( 'json', $json_turn['tool_calls'][0]['parameters']['query'] ?? '', 'fenced JSON fallback decodes function arguments', $failures, $passes );
 
+$function_call_turn = AgentsAPI\AI\WP_Agent_Provider_Turn_Result::normalize(
+	array(
+		'content' => '{"type":"function_call","function_call":{"name":"client/lookup","arguments":{"query":"wrapped"}}}',
+	)
+);
+agents_api_smoke_assert_equals( 'client/lookup', $function_call_turn['tool_calls'][0]['name'] ?? '', 'function_call wrapper extracts tool name', $failures, $passes );
+agents_api_smoke_assert_equals( 'wrapped', $function_call_turn['tool_calls'][0]['parameters']['query'] ?? '', 'function_call wrapper decodes object arguments', $failures, $passes );
+
 $tag_turn = AgentsAPI\AI\WP_Agent_Provider_Turn_Result::normalize(
 	array(
 		'content' => '<tool_call name="client/lookup">{"query":"tag"}</tool_call>',