[deep-report] Fix claude engine "Fast mode unavailable" crash in 4+ workflows #30170

Description

Four Claude-engine workflows are consistently failing with Fast mode unavailable: Fast mode is not available in the Agent SDK. This causes immediate termination before any agent output is produced. Affected workflows (all failing as of 2026-05-04):

• GitHub MCP Structural Analysis (§25318705928) — never produced successful output; Q:20/100, E:10/100 per Agent Performance Report
• Multi-Device Docs Tester (§25304397726)
• Schema Consistency Checker (§25304247413)
• Design Decision Gate (§25322480841)

The error likely stems from fast_mode: true or --fast flags in affected workflow configs where the Agent SDK does not support that mode.

Expected Impact

Restores 4 Claude-engine workflows to operation and eliminates daily failure-issue spam. GitHub MCP Structural Analysis has zero successful runs in the recent window — fixing it unblocks an important analysis workflow.

Suggested Agent

Any coding agent with workflow YAML access. Search for fast_mode or --fast flags in affected .github/workflows/*.lock.yml or harness startup configs.

Estimated Effort

Quick (< 1 hour) — likely a one-line config change per affected workflow.

Data Source

DeepReport Intelligence Briefing — 2026-05-04 (run §25327289278)

Generated by DeepReport - Intelligence Gathering Agent · ● 301.8K · ◷

• expires on May 6, 2026, 3:29 PM UTC