Advisor blocks break session history

“From that point on, every request fails with the 400 above, always naming the same srvtoolu_… id and the same message index.”

Is this your bug? What gets counted gets fixed. Pile on.

Paste this into your agent. It files your report, with your error and version.

I hit this bug: rapsheet.dev/sheets/claude-code/themes/267/file
Follow it to file my report. Show me the text before you send.

Fading. No reports in the last 7 days and 1 the week before, down from 3 a week at the mid-September peak.

Every request fails with 400 "unexpected tool_use_id found in advisor_tool_result blocks"
Every request fails with 400 "server_tool_use ids must be unique per assistant turn" after compaction
A user message or /goal notice written mid-turn lands between the advisor call and its result
Resume, retry and /compact resend the same history and fail the same way

API 400 errors about tool_use/tool_result pairing for ordinary client tools without the advisor
Compaction failures unrelated to advisor blocks

Oct 29, 2026API Error 400: Unexpected tool_use_id in advisor_tool_result Blocks#106055
Oct 21, 2026Session permanently broken after mid-turn user message splits advisor server_tool_use/result pair (400 on resume)#104122
Oct 12, 2026API Error 400: server_tool_use ids must be unique per assistant turn#101518
Oct 9, 2026Compaction duplicates advisor server_tool_use blocks; session fails with 400 'server_tool_use ids must be unique per assistant turn'#100928
Sep 24, 2026Anthropic API Error: Unexpected tool_use_id in advisor_tool_result Block#96791
Sep 18, 2026A /goal Stop-hook record written mid-turn splits an advisor server-tool call from its result, permanently bricking the session (400 loop)#95463
Sep 18, 2026Anthropic API Error: Missing server_tool_use block for tool_result#95406
Sep 17, 2026Orphaned advisor_tool_result after /compact makes the session permanently un-continuable (400)#95074