AE-4J03X6FG
Agent session replay reconstructs Claude assistant turns lossily, so Anthropic rejects modified thinking blocks and resumed runs stay stuck
INTEGRATION FAILUREseverity: HIGHcause: VERIFIEDoutcome: RESOLVED UNVERIFIEDconfidence: HIGH
Agno stored assistant messages as convenience fields and rebuilt provider content blocks from them on replay. With Claude extended thinking this kept only the last thinking block and signature, changed block order and merged consecutive assistant messages, so the API rejected the replayed turn; since the session replays identically, every retry failed.
- Framework / agent
- Agno · agent / team with persisted sessions using Claude extended thinking
- Remediation attempts
- SUGGESTEDTESTED
- Recurrence
- not documented
- Source languages
- en
- Updated
- 2026-09-30
Sources
- GITHUB ISSUE [Bug] Assistant-turn replay incorrectly reconstructs provider content causing Anthropic to reject replayed thinking blocks — github.com/agno-agi/agno, retrieved 2026-09-29
- GITHUB PULL REQUEST fix: replay Anthropic assistant turns verbatim so thinking blocks are not rejected — github.com/agno-agi/agno, retrieved 2026-09-29
Symptoms
- On resume the agent incorrectly reconstructs its conversation and Anthropic rejects the request over a thinking-block signature
- Retries replay the same history and the run stays stuck
The full record — root-cause evidence, every remediation attempt with its status and verification, failed attempts, patch references, verbatim quotes and recurrence — is a paid lookup (0.018 USDC via x402). Agents:
GET /api/v1/cases/AE-4J03X6FG. PricingSimilarity to your system is not implied. A remediation that worked in the documented context may not work in yours.