[copilot-opt] Centralize shared workflow formatting instructions to prevent recurring prompt drift across reporting workflows #28707

Problem

Multiple workflows are missing standard formatting instructions that are present in the canonical daily-performance-summary.md workflow. This causes prompt drift — different workflows produce inconsistent report structures (header levels, collapsible sections) despite having identical output requirements. The symptom was observed across audit-workflows.md, daily-regulatory.md, and daily-safe-output-integrator.md, all of which had to be patched separately. Each patch was a separate Copilot session.

Evidence

• Analysis window: 2026-04-13 to 2026-04-27
• PRs analyzed: 1,000; sessions with formatting-related patches: ≥3
• Key metrics and examples:
  • PR body: "Three daily reporting workflows lacked the standard markdown formatting instructions already present in daily-performance-summary.md, leading to inconsistent report structure across automated discussions and PRs."
  • Fix required patching 3 separate workflow files (audit-workflows.md, daily-regulatory.md, daily-safe-output-integrator.md) — each a separate agent session
  • Root pattern: formatting instructions are copy-pasted into individual workflow prompts rather than being centrally sourced, so new workflows are created without them
  • Similarly, the MCP context canceled fix was copy-pasted into a single workflow; if bash-validation guidance were centrally sourced, no copy would be needed

Proposed Change

1. Extract shared formatting and validation instructions into a canonical shared import (e.g., shared/report-formatting.md and shared/validation-strategy.md) that workflow authors import: instead of copy-pasting.
2. Add a lint/compile check that warns when a reporting workflow's prompt does not import the shared formatting guideline (similar to the existing schema validation pattern).
3. Audit all existing daily/weekly reporting workflows for missing formatting imports and fix in a single batch PR rather than individual reactive fixes.

Expected Impact

• Eliminate recurring "format consistency fix" PRs (≥3 observed in this window) by making the correct behavior the path of least resistance
• Prevent prompt drift as new reporting workflows are added — one update to the shared import propagates everywhere
• Reduce total Copilot sessions for maintenance patches by consolidating recurring textual fixes into reusable components

Notes

• Distinct root cause category: copy-paste instruction propagation instead of shared imports
• Data quality caveats: Exact count of all affected workflows unknown; 3 confirmed from PR evidence. The sessions-list.json covers only 2026-04-27; full 14-day session logs were not accessible due to authentication constraints on the log files.

Generated by Copilot Opt · ● 955.5K · ◷