feat(mcp): add reference_time parameter to add_memory tool

[daniel-rudaev]

Summary

The add_memory MCP tool currently hardcodes reference_time to datetime.now(UTC) in the queue service, even though the underlying Graphiti.add_episode() fully supports it. This means all ingested episodes get the current timestamp regardless of when the content actually occurred, breaking temporal reasoning for historical data.

Use case: When ingesting conversation exports (e.g., ChatGPT, Gmail) spanning years, each episode should carry its original date so Graphiti can correctly:

• Set valid_at on extracted facts to reflect when events actually happened
• Use the previous-episode context window with correct temporal ordering
• Invalidate edges based on actual chronology, not ingestion order

Changes

• Add optional reference_time (ISO 8601 string) parameter to add_memory tool
• Parse and pass through to QueueService.add_episode()
• QueueService passes to Graphiti.add_episode() instead of hardcoding datetime.now()
• Falls back to datetime.now(UTC) when not provided (preserving existing behavior)

Files changed

• mcp_server/src/graphiti_mcp_server.py — add param to tool signature + docstring, parse ISO 8601, forward to queue service
• mcp_server/src/services/queue_service.py — accept + forward reference_time, log it

Test plan

• Verify add_memory without reference_time still works (defaults to now)
• Verify add_memory with reference_time="2023-06-15T12:00:00Z" sets valid_at on extracted facts to ~2023-06-15
• Verify invalid reference_time string logs a warning and falls back to now
• Verify relative temporal expressions in content (e.g. "last week") are resolved against the provided reference_time

🤖 Generated with Claude Code

[danielchalef]

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[daniel-rudaev]

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