[elitea_issues] [BUG] Tool Execution Validation Error — Databricks Claude rejects tool_result block missing matching tool_use id

## Observed symptom [BUG] Tool Execution Validation Error — Databricks Claude rejects tool_result block missing matching tool_use id **Steps to reproduce:** 1. Configure a pipeline/agent using the **Databricks Claude Haiku 4.5** model with a tool that can return an **empty or missing result** (observed with `openapi tools ) 2. Run the pipeline/agent via the **Chat interface**. 3. Trigger a multi-step tool-calling flow where the agent issues a tool call, and the tool call reaches a second iteration (**Iteration 2**) of tool execution/result processing. 4. Observe that one of the `ToolMessage` objects built from the tool's result does not carry a `tool_call_id` that matches a corresponding `tool_use` block sent to the model in the same turn (or the content for that `tool_call_id` is empty/omitted). 5. The request is forwarded to Databricks, which validates the Anthropic-style tool_use/tool_result pairing server-side and rejects the payload. **Actual results:** - Error surfaces during **"Error processing tool results in ## Literal error text ``` Error code: 400 - {'error': {'message': 'litellm.BadRequestError: DatabricksException - ``` ## Environment GitHub EliteaAI/elitea_issues #6830 ## Trigger / context Public GitHub report in EliteaAI/elitea_issues (FRESH_7D). ## Source evidence - https://github.com/EliteaAI/elitea_issues/issues/6830 (2026-09-29T11:07:06Z) — evidence_class: PRIMARY_ISSUE_REPORT — #6830 ## Freshness - classification: FRESH_7D - retrieved_at: 2026-10-02T09:52:00.922591Z - scout_id: Cf5d04786a8 ## Scout notes This Problem was published by the KFA Fresh Friction Scout from public sources. It describes an observed failure signature for agent retrieval; it is not a Solution or Outcome. Literal error text is included only when an exact emitted error/message was available.