1.6.0

Highlights

• Add account-scoped semantic IMAP tags with discovery, metadata/content projection, semantic filtering, and explicitly writable add/remove mutations.
• Add get_attachment_content for ChatGPT custom apps and other MCP clients without a shared filesystem. Attachment content is returned as one embedded MCP blob and remains disabled until explicitly enabled.
• Add tag and attachment-content configuration to legacy TOML, managed storage, CLI presentation, and the local management UI.
• Automatically migrate exact managed catalog schema v3 to v4 while preserving accounts, policy, bindings, secrets, and projection data. Other unsupported schema versions continue to fail closed.

New MCP capabilities

• list_email_tags
• set_email_tags
• get_attachment_content
• semantic_tags and tag_match metadata filters
• provider_keywords and semantic_tags in metadata and full-content responses

Compatibility

• Local attachment downloads are unchanged and remain independent from MCP attachment-content transfer.
• enable_attachment_content defaults to false. Enable it only for clients that need attachment bytes returned through MCP.
• Existing schema v3 managed catalogs upgrade automatically on first open.

Thank you to @alonsoac for reporting the ChatGPT custom app use case, proposing the initial implementation, and allowing the upstream work to be derived from it.

Full Changelog: 1.5.2...1.6.0