1 files changed, 20 insertions, 12 deletions

diff --git a/libpanto/src/provider_anthropic_messages.zig b/libpanto/src/provider_anthropic_messages.zig
index e77d6a5..55efb5f 100644
--- a/libpanto/src/provider_anthropic_messages.zig
+++ b/libpanto/src/provider_anthropic_messages.zig
@@ -33,6 +33,8 @@ pub const AnthropicMessagesRequest = struct {
     io: Io,
     config: *const config_mod.AnthropicMessagesConfig,
     http_client: *http.Client,
+    /// Optional diagnostic side-channel; see `OpenAIChatRequest.diag`.
+    diag: ?*provider_mod.ProviderDiagnostic = null,
 
     pub fn streamStep(
         self: *AnthropicMessagesRequest,
@@ -106,17 +108,18 @@ pub const AnthropicMessagesRequest = struct {
                 try err_buf.appendSlice(self.allocator, tmp[0..n]);
                 if (err_buf.items.len > 16 * 1024) break;
             }
-            std.log.err("anthropic_messages HTTP {d}: {s}", .{
-                @intFromEnum(response.head.status),
-                err_buf.items,
-            });
+            const status: u16 = @intFromEnum(response.head.status);
+            std.log.err("anthropic_messages HTTP {d}: {s}", .{ status, err_buf.items });
             // Anthropic rejects oversized requests with HTTP 400 and a
-            // "prompt is too long" message; surface as ContextOverflow so
-            // the caller can compact and retry.
-            if (@intFromEnum(response.head.status) == 400 and provider_mod.isContextOverflowBody(err_buf.items)) {
-                return error.ContextOverflow;
+            // "prompt is too long" message; `classifyHttpStatus` maps that to
+            // ContextOverflow so the caller can compact and retry. Other
+            // statuses map to retryable/terminal provider errors.
+            const classified = provider_mod.classifyHttpStatus(status, err_buf.items);
+            if (self.diag) |d| {
+                d.status_code = status;
+                d.retry_after_ms = provider_mod.retryAfterFromHead(response.head);
             }
-            return error.HttpError;
+            return classified;
         }
 
         var transfer_buf: [4096]u8 = undefined;
@@ -140,7 +143,8 @@ pub const AnthropicMessagesRequest = struct {
         while (true) {
             const n = body_reader.readVec(&vecs) catch |err| switch (err) {
                 error.EndOfStream => break,
-                else => return err,
+                // Transport failure before the message completed: retryable.
+                else => return error.ProviderStreamMalformed,
             };
             if (n == 0) continue;
 
@@ -473,7 +477,9 @@ fn handleEvent(
             if (!@import("builtin").is_test) {
                 std.log.err("anthropic stream error: {?s}: {?s}", .{ e.kind, e.message });
             }
-            return error.StreamError;
+            // Mid-stream error event (e.g. `overloaded_error`) before the
+            // message was committed: retryable malformed-stream failure.
+            return error.ProviderStreamMalformed;
         },
         .unknown => {
             // Forward-compatible: ignore unknown event types per Anthropic's
@@ -543,12 +549,14 @@ const RecordingReceiver = struct {
         .onBlockComplete = onBlockComplete,
         .onMessageComplete = onMessageComplete,
         .onError = onError,
+        .onProviderRetry = onProviderRetry,
     };
 
     fn onMessageStart(ptr: *anyopaque, role: conversation.MessageRole) anyerror!void {
         const self: *RecordingReceiver = @ptrCast(@alignCast(ptr));
         try self.events.append(self.allocator, .{ .message_start = role });
     }
+    fn onProviderRetry(_: *anyopaque, _: provider_mod.ProviderRetryInfo) void {}
     fn onBlockStart(
         ptr: *anyopaque,
         bt: provider_mod.ContentBlockType,
@@ -988,7 +996,7 @@ test "error event propagates as Zig error" {
         &state,
         &recv,
     );
-    try testing.expectError(error.StreamError, result);
+    try testing.expectError(error.ProviderStreamMalformed, result);
 }
 
 test "two streamed turns persist assistant replies in the conversation" {