Account for the relationship as it is now
Use a tone that fits the present relationship, not the closeness, authority, or access that existed in the past. For a message about how to reconnect with a former coworker about work, use this factual base: remind the person where you worked together, when, and what current topic makes the contact relevant.
Ask without assigning an obligation
Explain what you hope for while making decline, delay, or a different format genuinely acceptable. Make one modest request and give enough information for them to decline or redirect it. Make the immediate next step clear enough that the recipient can answer without reconstructing the entire history.
Keep the ending honest
Do not imply endorsement, exploit a former hierarchy, or send confidential material from the old relationship. Use official business, privacy, conflict, and procurement rules when commercial or regulated information is involved. Avoid future promises, guilt, flattery, or nostalgia that imply the recipient owes you access.