Merge #21: repair dangling tool_use on every request, not just load

Run repairToolUseResultPairs on outbound messages in oneTurn so an
in-process aborted turn (cancel, connection drop, ECONNREFUSED) no
longer leaves a dangling tool_use that gets rejected by Anthropic/OpenAI
on the next request. Pure and idempotent, no-op on valid transcripts.

commit: 3d031dde263236f77cdd2cb6a7ac69fbce71d278
author: patriceckhart · 4mo ago · 2026-06-09 10:58 UTC
merge of: f7bf4a9 + b25b860 · diff against the first parent
signature: unsigned
refs: tag: v0.2.22

1 file · +11 -3

M packages/core/agent.go +11 -3


@@ -502,9 +502,17 @@ func (a *Agent) dropLastAssistantMessage() {
502	502		// and the assembled assistant message (already appended to the transcript).
503	503		func (a *Agent) oneTurn(ctx context.Context, sink func(AgentEvent)) (provider.StopReason, provider.Message, error) {
504	504		req := provider.Request{
505		-	Model: a.Model,
506		-	System: a.System,
507		-	Messages: a.Messages(),
	505	+	Model: a.Model,
	506	+	System: a.System,
	507	+	// Repair any dangling tool_use blocks before sending. A turn
	508	+	// aborted mid-flight (cancel, connection drop, ECONNREFUSED to a
	509	+	// dev server, etc.) can leave an assistant tool_use with no
	510	+	// matching tool_result in the live transcript. The load-time
	511	+	// repair in OpenSession only runs on restart, so without this the
	512	+	// next in-process request is rejected by providers like Anthropic
	513	+	// with "tool_use ids were found without tool_result blocks". The
	514	+	// repair is pure and a no-op on already-valid transcripts.
	515	+	Messages: repairToolUseResultPairs(a.Messages()),
508	516		Tools: a.Tools.Specs(),
509	517		Reasoning: a.Reasoning,
510	518		}

 // and the assembled assistant message (already appended to the transcript).
 func (a *Agent) oneTurn(ctx context.Context, sink func(AgentEvent)) (provider.StopReason, provider.Message, error) {
 	req := provider.Request{
-		Model:     a.Model,
+		Model:  a.Model,
-		System:    a.System,
+		System: a.System,
-		Messages:  a.Messages(),
+		// Repair any dangling tool_use blocks before sending. A turn
+		// aborted mid-flight (cancel, connection drop, ECONNREFUSED to a
+		// dev server, etc.) can leave an assistant tool_use with no
+		// matching tool_result in the live transcript. The load-time
+		// repair in OpenSession only runs on restart, so without this the
+		// next in-process request is rejected by providers like Anthropic
+		// with "tool_use ids were found without tool_result blocks". The
+		// repair is pure and a no-op on already-valid transcripts.
+		Messages:  repairToolUseResultPairs(a.Messages()),
 		Tools:     a.Tools.Specs(),
 		Reasoning: a.Reasoning,
 	}