Lore Email Archive Search Guide

February 6, 2026 · View on GitHub

This guide explains how to use semcode's lore.kernel.org email archive search features in both the query tool and the MCP server.

Overview

Semcode can index and search lore.kernel.org email archives, providing Full Text Search (FTS) with regex post-filtering and semantic search capabilities across mailing list archives. This is particularly useful for finding discussions about specific commits, patches, or topics in kernel development.

How It Works: FTS + Regex Hybrid Approach

All lore searches use a two-phase approach for fast, precise results:

  1. Phase 1: FTS (Full Text Search) - Fast keyword-based search using inverted indices

    • Patterns are normalized by extracting keywords (special chars stripped)
    • Example: "[PATCH v2]" → "PATCH v2" for FTS
    • Returns a superset of candidates very quickly

  2. Phase 2: Regex Post-Filter - Precise filtering in memory

    • Original regex pattern applied to FTS results
    • Ensures exact matching (e.g., "clm@meta.com" matches exactly)
    • Fast because operating on small FTS result set

Date Filtering

All lore search commands (lore, dig, vlore) support date filtering with --since and --until flags to restrict results to specific time ranges.

Supported Date Formats

The date filters accept flexible formats for user convenience:

Absolute Dates:

  • YYYY-MM-DD format (e.g., "2024-01-15")
  • Times are assumed to be midnight (00:00:00) UTC

Relative Dates:

  • "today" - Start of current day (00:00:00 UTC)
  • "yesterday" - Start of previous day (00:00:00 UTC)
  • "N days ago" - N days before current time (e.g., "7 days ago", "30 days ago")
  • "N weeks ago" - N weeks before current time (e.g., "2 weeks ago")
  • "N months ago" - N months before current time (e.g., "3 months ago")

How Date Filtering Works

  1. RFC 2822 Format: Email dates are stored in RFC 2822 format (e.g., "Thu, 21 Nov 2019 14:22:24 -0800")
  2. Temporal Comparison: Dates are parsed and compared as datetime objects (not string comparison)
  3. Inclusive Ranges:
    • --since includes emails from that date onwards (≥)
    • --until includes emails up to and including that date (≤)
  4. Combine Both: Use both flags to define a specific date range

Date Filter Examples

# Recent activity
lore -s "PATCH" --since "7 days ago"          # Patches from last week
vlore --since "today" "memory leak"           # Today's emails about memory leaks

# Specific time periods
lore -f torvalds --since "2024-01-01" --until "2024-03-31"  # Q1 2024
dig --since "2023-01-01" --until "2023-12-31" HEAD          # All of 2023

# Open-ended ranges
lore -b btrfs --since "2024-01-01"            # From 2024 onwards
lore -g malloc --until "2023-12-31"           # Before 2024

# Relative dates for recent searches
vlore --since "yesterday" "kernel bug"        # Yesterday and today
dig --since "30 days ago" abc123              # Last month of discussion

Use Cases for Date Filtering

  • Recent activity: Find current discussions with --since "7 days ago"
  • Historical research: Study specific time periods with --since YYYY-MM-DD --until YYYY-MM-DD
  • Version tracking: Filter by release dates to see discussion before/after a release
  • Performance: Reduce result sets by limiting to relevant time periods

Setup: Indexing a Lore Archive

Before searching, you need to clone and index a lore archive:

# Index a lore archive (e.g., linux kernel mailing list)
semcode-index --lore lkml

# Index multiple lists at once
semcode-index --lore lkml,bpf

# The archive will be cloned to <db_dir>/lore/<repo_name>
# In this example: .semcode.db/lore/linux-kernel

Refreshing Existing Archives

To fetch new emails and index them without re-specifying archive names:

# Refresh all previously cloned lore archives
semcode-index --lore

When called without arguments, --lore discovers all git repositories under <db_dir>/lore/, fetches new commits from each remote, and indexes any emails not yet in the database. Use this for a simple one-command workflow to keep lore archives up to date.

To enable semantic search with the vlore command:

# Generate vector embeddings for indexed emails
semcode-index --lore lkml --vectors

Note: Vector generation is optional but required for the vlore command.

Query Tool Commands

1. lore - Search Emails by Field

Search lore emails using regex patterns on different fields (from, subject, body, recipients, symbols).

Syntax:

lore [-v] [-m <message_id>] [-f <regex>] [-s <regex>] [-b <regex>] [-t <regex>] [-g <regex>] [--limit <N>] [--since <date>] [--until <date>] [--thread] [--replies] [-o <output_file>]

Options:

  • -v - Verbose mode: show full message bodies
  • -m <message_id> - Look up a specific email by Message-ID
  • -f <regex> - Filter by From address (can be specified multiple times)
  • -s <regex> - Filter by Subject line (can be specified multiple times)
  • -b <regex> - Filter by message Body (can be specified multiple times)
  • -t <regex> - Filter by recipients (To/Cc) (can be specified multiple times)
  • -g <regex> - Filter by symbols mentioned in any patches (can be specified multiple times)
  • --limit <N> - Maximum number of results (default: 100)
  • --since <date> - Only show emails from this date onwards (see Date Filtering section below)
  • --until <date> - Only show emails up to this date (see Date Filtering section below)
  • --thread - Show full email threads for each match (walks up to root, then shows all descendants)
  • --replies - Show all replies/subthreads under each match (shows descendants only, not ancestors)
  • -o <output_file> - Write output to file instead of stdout

Note: --thread and --replies are mutually exclusive.

Filter Logic:

  • Multiple filters for the same field are combined with OR logic
    • Example: -f torvalds -f gregkh matches emails from torvalds OR gregkh
  • Filters for different fields are combined with AND logic
    • Example: -f torvalds -b btrfs matches emails from torvalds AND body contains btrfs

Regex Tips:

  • Case-insensitive by default: All regex patterns are automatically case-insensitive
    • Example: -s 'patch' matches "patch", "PATCH", "Patch", etc.
    • No need to use the (?i) flag
  • For multiline matching (e.g., matching start of line within email body), use the (?m) flag
    • Example: -b '(?m)^Signed-off-by' matches "Signed-off-by" at the start of any line
    • Without (?m), ^ and $ only match the start/end of the entire field

Examples:

# Search by subject
lore -s "memory leak"

# Search with verbose output and limit
lore -v -s "performance" --limit 50

# Search by sender
lore -f "torvalds@linux-foundation.org"

# Search by recipient
lore -t "netdev@vger.kernel.org"

# Search message body
lore -b "Signed-off-by.*Linus"

# Search by symbols mentioned in patches
lore -g "malloc"
lore -g "struct.*page"

# Look up specific email by Message-ID
lore -m "<20241201120000.12345@kernel.org>"

# Show threads (full thread including ancestors)
lore -v -f "torvalds" --thread
lore -v -s "memory leak" --thread --limit 5

# Show replies only (descendants, not ancestors)
lore -v -s "RFC" --replies
lore -m "<message.id@example.com>" --replies

# Combine filters (AND across fields)
lore -b btrfs -f clm@meta.com              # Body contains btrfs AND from clm@meta.com
lore -f torvalds -f gregkh -b "memory leak" # From torvalds OR gregkh AND body contains memory leak
lore -g "schedule.*" -f "torvalds"         # Symbols match schedule.* AND from torvalds

# Write output to file
lore -v -s "memory leak" -o results.txt    # Save verbose results to file
lore -f torvalds --thread -o threads.txt   # Save thread view to file

# Date filtering
lore -s "memory leak" --since "2024-01-01"        # Emails from Jan 1, 2024 onwards
lore -f torvalds --until "2023-12-31"              # Emails up to Dec 31, 2023
lore -b btrfs --since "7 days ago"                 # Emails from last week
lore -s "PATCH" --since "yesterday"                # Emails from yesterday onwards
lore -g malloc --since "2024-01-01" --until "2024-06-30"  # First half of 2024

Output Format:

  • Summary view (default): Date, subject, from, Message-ID, and threading info
  • Verbose view (-v): Includes full message body
  • Thread view (--thread): Shows complete email threads in chronological order (walks up to root, then shows entire thread)
  • Replies view (--replies): Shows all replies/subthreads under each match (descendants only, useful for seeing discussion that followed)

Search for lore emails related to a specific git commit by matching the commit's subject line. Results are ordered by date (newest first).

Syntax:

dig [-v] [-a] [--since <date>] [--until <date>] [--thread] [--replies] <commit>

Options:

  • -v - Verbose mode: show full message bodies
  • -a - Show all matching emails (default: only most recent)
  • --since <date> - Only show emails from this date onwards (see Date Filtering section below)
  • --until <date> - Only show emails up to this date (see Date Filtering section below)
  • --thread - Show full email threads for each match
  • --replies - Show all replies/subthreads under each match
  • <commit> - Any git reference (SHA, short SHA, branch name, HEAD, etc.)

Note: --thread and --replies are mutually exclusive.

Examples:

# Show most recent match thread for HEAD commit
dig HEAD

# Show most recent match with message body
dig -v abc123

# Show all matches (summary)
dig -a v6.5

# Show all matches with full threads
dig -a --thread HEAD

# Show all matches with threads and bodies
dig -v -a --thread abc123

# Show all matches with just replies (no ancestors)
dig -a --replies HEAD

# Show replies to most recent match
dig --replies abc123

# Date filtering
dig --since "2024-01-01" HEAD                  # Only emails from 2024 onwards
dig --until "2023-12-31" abc123                # Only emails from before 2024
dig -a --since "30 days ago" HEAD              # All matches from last 30 days
dig --since "2024-01-01" --until "2024-06-30" v6.5  # First half of 2024

How It Works:

  1. Resolves the git reference to a commit SHA
  2. Extracts the commit's subject line
  3. Searches lore emails for exact subject matches
  4. Shows results ordered by date (newest first)
  5. By default shows only the most recent match; use -a to see all

Use Cases:

  • Find mailing list discussion about a specific patch
  • See review feedback for a commit
  • Track the history of how a patch evolved from email to merge

Search for lore emails similar to the provided text using semantic vector embeddings. This allows you to find conceptually related discussions even when exact keywords don't match.

Syntax:

vlore [-f <from_regex>] [-s <subject_regex>] [-b <body_regex>] [-g <symbols_regex>] [-t <recipients_regex>] [--limit <N>] [--since <date>] [--until <date>] <query_text>

Options:

  • -f <from_regex> - Filter results by From address (can be specified multiple times)
  • -s <subject_regex> - Filter results by Subject (can be specified multiple times)
  • -b <body_regex> - Filter results by message Body (can be specified multiple times)
  • -g <symbols_regex> - Filter results by symbols mentioned in patches (can be specified multiple times)
  • -t <recipients_regex> - Filter results by Recipients/To/Cc (can be specified multiple times)
  • --limit <N> - Maximum number of results (default: 20, max: 100)
  • --since <date> - Only show emails from this date onwards (see Date Filtering section below)
  • --until <date> - Only show emails up to this date (see Date Filtering section below)
  • <query_text> - Search query (required)

Prerequisites: Vector embeddings must be generated first:

semcode-index --lore <url> --vectors

Examples:

# Basic semantic search
vlore "memory leak fix"

# With custom limit
vlore --limit 10 "performance optimization"

# Filter by sender
vlore -f "torvalds" "merge pull request"

# Multiple subject filters (OR logic)
vlore -s "RFC" -s "PATCH" "new feature"

# Body filter
vlore -b "Signed-off-by.*Linus" "kernel patch"

# Symbol filter
vlore -g "malloc" "memory management"

# Recipients filter
vlore -t "netdev@vger.kernel.org" "network patch"

# Date filtering
vlore --since "2024-01-01" "memory leak fix"             # Emails from 2024 onwards
vlore --until "2023-12-31" "performance optimization"    # Emails from before 2024
vlore --since "30 days ago" "kernel bug"                 # Recent emails from last month
vlore --since "2024-01-01" --until "2024-06-30" "btrfs"  # First half of 2024

When to Use Semantic vs Regex Search:

  • Use vlore for: Finding conceptually similar discussions, broad topic searches, when you're not sure of exact keywords
  • Use lore for: Exact pattern matching, specific authors or subjects, precise filtering

4. dump-lore (alias: dlore) - Export All Emails

Export all indexed lore emails to a JSON file for external processing.

Syntax:

dump-lore <output_file>

Example:

dump-lore emails.json

Output Format: JSON array of email objects with fields: message_id, subject, from, date, body, recipients, in_reply_to, references.

MCP Server Tools

The semcode MCP server exposes the same lore search functionality for use with Claude Desktop and other MCP clients.

Search lore emails with regex filters. Same functionality as the query tool's lore command.

Parameters:

  • message_id (string, optional) - Specific Message-ID to look up
  • from_patterns (array of strings, optional) - From address regex patterns (OR logic)
  • subject_patterns (array of strings, optional) - Subject regex patterns (OR logic)
  • body_patterns (array of strings, optional) - Body regex patterns (OR logic)
  • recipient_patterns (array of strings, optional) - Recipient regex patterns (OR logic)
  • symbols_patterns (array of strings, optional) - Symbols regex patterns (OR logic)
  • limit (number, optional) - Maximum results (default: 100)
  • since_date (string, optional) - Only show emails from this date onwards (see Date Filtering section below)
  • until_date (string, optional) - Only show emails up to this date (see Date Filtering section below)
  • verbose (boolean, optional) - Show full message bodies (default: false)
  • show_thread (boolean, optional) - Show full threads (default: false)
  • show_replies (boolean, optional) - Show all replies/subthreads (default: false, mutually exclusive with show_thread)

Example Usage in Claude Desktop:

When you ask Claude to search lore archives, it will automatically use this tool:

"Search lore for emails from Linus Torvalds about btrfs"
"Find emails with subject containing 'memory leak' and show threads"
"Look up email with message_id <20241201120000.12345@kernel.org>"

MCP Tool: dig

Search for lore emails related to a git commit. Same functionality as the query tool's dig command.

Parameters:

  • commit (string, required) - Git reference (SHA, short SHA, branch, HEAD, etc.)
  • verbose (boolean, optional) - Show full message bodies (default: false)
  • show_all (boolean, optional) - Show all matches vs most recent (default: false)
  • since_date (string, optional) - Only show emails from this date onwards (see Date Filtering section below)
  • until_date (string, optional) - Only show emails up to this date (see Date Filtering section below)
  • show_thread (boolean, optional) - Show full threads (default: false)
  • show_replies (boolean, optional) - Show all replies/subthreads (default: false, mutually exclusive with show_thread)

Example Usage in Claude Desktop:

"Find lore emails related to commit abc123"
"Show all lore discussions about HEAD commit with threads"

MCP Tool: vlore_similar_emails

Semantic vector search for similar lore emails. Same functionality as the query tool's vlore command.

Parameters:

  • query_text (string, required) - Search query
  • from_patterns (array of strings, optional) - From address filters
  • subject_patterns (array of strings, optional) - Subject filters
  • body_patterns (array of strings, optional) - Body filters
  • symbols_patterns (array of strings, optional) - Symbols filters
  • recipients_patterns (array of strings, optional) - Recipients/To/Cc filters
  • limit (number, optional) - Maximum results (default: 20, max: 100)
  • since_date (string, optional) - Only show emails from this date onwards (see Date Filtering section below)
  • until_date (string, optional) - Only show emails up to this date (see Date Filtering section below)
  • verbose (boolean, optional) - Show full message bodies (default: false)

Prerequisites: Vector embeddings must be generated with semcode-index --lore <url> --vectors.

Example Usage in Claude Desktop:

"Find lore emails similar to 'memory leak fix'"
"Search for emails like 'performance optimization' from Linus"

Database Schema

Lore emails are stored in the lore table with the following structure:

FieldTypeDescription
message_idstringUnique Message-ID (primary key)
subjectstringEmail subject line
fromstringSender email address
datestringISO 8601 timestamp
bodystringFull message body (headers stripped)
recipientsstringComma-separated To/Cc recipients
symbolsJSON arrayList of symbols (functions, types, macros) extracted from patches
in_reply_tostringMessage-ID of parent email (if reply)
referencesstringSpace-separated Message-IDs of thread ancestors
git_commit_subjectstringExtracted commit subject (for patches)
commit_shastringGit SHA (for patches)

Vector embeddings (if generated) are stored in the lore_vectors table.

Common Use Cases

Finding Patch Discussion

# Find discussion about a specific commit
dig abc123

# See all versions and reviews
dig -a --thread abc123

Tracking Maintainer Communication

# All emails from a specific maintainer about a topic
lore -f "torvalds@" -b "btrfs"

# Show full threads
lore -f "torvalds@" -b "btrfs" --thread

# Show just the replies to see discussion that followed
lore -f "torvalds@" -b "btrfs" --replies

Research Topic History

# Semantic search for broad topic
vlore "memory management improvements"

# Exact pattern search
lore -s "mm:" -b "page.*allocation"

Analyzing Patch Series

# Find all patches in a series
lore -s "\[PATCH.*\]" -f "developer@example.com" --limit 50

# Show as threads to see review flow
lore -s "\[PATCH v2" --thread

# Show just the replies to see what reviewers said
lore -s "\[PATCH v2" --replies

Finding Patches by Symbol

# Find patches that modify a specific function
lore -g "malloc"

# Find patches touching memory management structures
lore -g "struct.*page"

# Combine symbol search with other filters
lore -g "schedule.*" -f "torvalds"
lore -g "mutex_lock" -s "\[PATCH" --limit 20

# Find patches modifying multiple related symbols (OR logic)
lore -g "kmalloc" -g "kfree" -g "vmalloc"

Tips and Best Practices

  1. Start broad, then narrow: Use semantic search (vlore) to find topics, then use regex search (lore) for precision

  2. Use threading wisely: The --thread flag is powerful but verbose. Use it when you need full context, not for initial exploration

  3. Choose between --thread and --replies:

    • Use --thread when you want to see the complete discussion from the beginning (includes ancestors)
    • Use --replies when you want to see only the responses to a specific email (excludes ancestors)
    • Example: For a patch email, --replies shows you what reviewers said without the full version history

  4. Leverage git integration: The dig command is the easiest way to find discussion about commits you're already looking at in git

  5. Combine filters effectively: Remember that same-field filters use OR logic, while different-field filters use AND logic

  6. Watch your limits: Large result sets can be overwhelming. Use --limit to control output size

  7. Message-ID lookups: If you see an interesting Message-ID in results, use lore -m <message_id> to view the full email

  8. Export for analysis: Use dump-lore when you need to process emails with external tools or scripts

Troubleshooting

"No lore table found"

You need to index a lore archive first:

semcode-index --lore https://lore.kernel.org/linux-kernel

"No similar emails found" with vlore

Vector embeddings need to be generated:

semcode-index --lore <url> --vectors

"No matching emails found"

  • Check your regex patterns - they may be too restrictive
  • Try broadening your search or removing some filters
  • Use semantic search (vlore) if regex isn't finding what you need

"Column has no inverted index" error

FTS indices need to be created after indexing:

# FTS indices are automatically created during --lore indexing
# If you see this error, re-run the indexing
rm -rf .semcode.db
semcode-index --lore <url>

Message-ID lookup tips

You can omit the < > brackets when using -m:

lore -m message.id@domain.com       # Works
lore -m <message.id@domain.com>     # Also works

See Also