Grafana-assembled rich reports (PNG export + narrative stitching)

[tallpsmith]

The Why

When Grafana is available and pmmcp has created a triage dashboard (#10), we have access to high-quality rendered chart images via mcp-grafana's get_panel_image and get_dashboard_image tools (requires Grafana Image Renderer plugin). These could be assembled into a portable, self-contained HTML/PDF report that combines real Grafana charts with Claude's narrative analysis — the best of both worlds.

Depends on: #10 (Grafana integration must be working first)

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Context from #10 Design

The #10 design established a visualisation fallback cascade:

1. Grafana dashboard (primary)
2. Claude-generated HTML file (fallback when no Grafana)
3. Text/table output (existing behaviour)

This issue adds a hybrid tier between 1 and 2: when Grafana IS available, pull rendered PNGs from the dashboard we just created and assemble them into a rich report file.

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Proposed Feature

After creating a triage dashboard in Grafana:

1. Use mcp-grafana.get_panel_image to export each panel as PNG
2. Claude assembles an HTML (or PDF) report combining:
   • Rendered chart images (base64-embedded in HTML)
   • Investigation narrative and interpretation
   • Statistical summaries (anomalies, correlations, comparisons)
   • Timeline of findings
3. Save to PMMCP_REPORT_DIR (same config as External Integration Contracts (Grafana MCP, reporting strategy) #10's HTML fallback)

Use Cases

• Post-incident reports for distribution (email to stakeholders, attach to Jira tickets)
• Offline analysis — the report is self-contained, no Grafana access needed to view
• Compliance/audit trail — portable artifact of what was investigated and found

Open Questions

• HTML with embedded base64 PNGs vs actual PDF generation? HTML is simpler; PDF is more "official"
• Should this be automatic ("here's your report") or on-demand ("generate a report from this investigation")?
• Does Grafana Enterprise's built-in PDF reporting make this redundant for Enterprise users?
• Image quality/resolution settings?
• How large do these files get with multiple panels? Any size concerns?

Prerequisites

• Grafana Image Renderer plugin must be installed on the user's Grafana instance
• mcp-grafana must expose get_panel_image / get_dashboard_image (confirmed available as of 2026-03)