Callimachus

Local index & search for your AI coding-agent threads across 12 tools (Claude Code, Codex, Cursor, Gemini CLI, Qwen Code, Goose, OpenCode, Continue, Cline, Roo Code, Kilo Code, Copilot Chat), plus a provider-agnostic chat, an MCP server, a CLI, and a VS Code / Cursor extension. Your history stays on your machine.

Named for Callimachus, who built the first catalogue of the Library of Alexandria.

Download

Grab the latest signed build from [Releases](../../releases/latest): macOS (.dmg, Apple Silicon), Windows (.msi or -setup.exe), or Linux (.AppImage, .deb or .rpm). The app auto-updates from there on. Prefer to build it yourself? See Develop.

macOS: drag Callimachus into Applications and open it from there before enabling the agent integration. While it runs from the disk image or a quarantined download, Settings won't register it, because that path disappears when the app quits.

Windows uninstall: the -setup.exe uninstaller removes what the app added (the /recall skill, the Claude Code, Codex and Gemini CLI hooks, the MCP entries for Claude Code, Codex, Cursor and Gemini CLI, and cal.exe), but the .msi uninstaller doesn't. Before removing an MSI install, click Remove for Claude Code and under Other agents in Settings → Agents (the Other agents Remove also takes out the Codex and Gemini CLI memory hooks), or run callimachus.exe --uninstall-integration; otherwise the hooks keep pointing at the deleted app and each agent reports a hook error at every session start.

The same release also carries standalone cal- and callimachus-mcp- binaries for CLI/MCP-only use, with their SHA-256 sums in SHA256SUMS. Linux builds and binaries need glibc 2.38 or newer (Ubuntu 24.04+, Debian 13+, Fedora 39+); Ubuntu 22.04, Debian 12 and RHEL 9 are too old for the bundled ONNX Runtime.

Updates: the first launch after an update upgrades the index in the background; the splash keeps animating, and on a large index this can take tens of seconds. An older build can't open an upgraded index: an older app shows "This index is from a newer Callimachus", and an older cal, callimachus-mcp or pinned npx callimachus-mcp@ stops with an error. Whichever of them opens the index first does the upgrade, so keep the app, the npx launcher and any standalone binaries on the same release.

What it does

• Indexes every conversation from 12 coding agents into one local SQLite store: Claude Code, Codex, Cursor, Gemini CLI, Qwen Code, Goose, OpenCode, Continue, Cline, Roo Code, Kilo Code, and Copilot Chat (the built-in chat panel of VS Code, Cursor, VSCodium and Windsurf). Adding another source is a small, documented contract.
• Searches them with hybrid ranking: keyword (SQLite FTS5 / BM25) fused with on-device semantic similarity (sqlite-vec KNN, no cloud) via Reciprocal Rank Fusion. Filter by source, project, subagents, starred, and tags.
• Finds code-aware: type file:embed/mod.rs in the search bar (or cal files ) to find every thread that touched a path; backed by a file-mention index built at index time.
• Distills knowledge: free heuristic TODO extraction (always on, no LLM), plus LLM distillation of decisions, gotchas, and summaries behind one consent click that names the engine and where transcripts go (the Turn on memory card in Projects or Chat's Ask mode preselects a detected Claude Code or Codex CLI, then local Ollama, then a saved key; Settings > AI engine has the same switch), with cross-thread semantic recall of past decisions/gotchas. Optional auto-distillation works through threads active in the last 30 days in the background, up to a daily limit you set next to its toggle (50 threads by default, 0 pauses it; Settings shows what's left today), so memory self-populates without an open-ended bill. Runs on local Ollama (keyless), your logged-in Claude Code or Codex CLI (keyless, billed to whatever that CLI is signed in with), or a cloud API key.
• Imports what agents already write: Claude Code's own auto memory (the topic files under ~/.claude/projects/ /memory/) joins each repo's project memory with no LLM: feedback memories become gotchas and project memories decisions, tagged "Claude Code memory", refreshed when a file changes and removed when it goes (Settings > Agents turns it off and removes them). The managed AGENTS.md / CLAUDE.md block and .callimachus/memory.md leave them out, since Claude Code already loads them and those files get committed. When auto-distillation is on, a SessionEnd hook moves the session that just ended to the front of the queue, so its memory lands minutes after it ends.
• Curates the facts: pin, edit, or hide distilled facts so your edits survive re-distilling, record a decision or gotcha yourself with Remember in the Projects tab (saved pinned), plus an LLM "Review conflicts" pass that flags decisions that contradict each other.
• Remembers per project: a Projects tab gives each repo one page: its recent sessions, its decisions, gotchas, and open TODOs aggregated into durable memory (grouped by a canonical project key, so worktrees / symlinks / ~ don't split one repo), its snapshots, and exactly what its agents are given (the SessionStart hook's text and the managed AGENTS.md block, with their sizes), plus an LLM brief and a managed .callimachus/memory.md. That memory is prepended when you "Open in CLI", and you can inject it into any agent automatically: Update AGENTS.md (or cal agents) writes a managed block into the repo's AGENTS.md / CLAUDE.md, and cal hook feeds a size-budgeted version to a Claude Code SessionStart hook, labeled as notes from past sessions rather than instructions. A repo with no memory yet still gets something on day one, with no LLM: a digest of its last few sessions (title, agent, branch, age, the latest summary or prompt, touched files, open TODOs, and the latest snapshot to resume), also appended under the facts when they leave room. The hook runs on startup, /clear and compaction (a shorter, facts-only refresher), stays quiet on a resumed session, and skips a repo where Claude Code already loads the managed block (a CLAUDE.md, CLAUDE.local.md or a file one @-imports, or AGENTS.md when no CLAUDE.md exists), so the memory is injected once. cal hook --explain shows what a new session would get, cal hook --mute turns the digest off for one repo, and Settings > Agents turns it off everywhere. Codex and Gemini CLI get the same memory through their own hooks (Settings > Agents > Other agents > Memory hooks): cal hook --for codex / --for gemini on session start and /clear (Codex also after compaction), wrapped in each agent's hook output format, plus their imported Claude Code memories, marked as such, since neither loads Claude's auto memory. The hook stays quiet in a repo whose AGENTS.md (Codex) or GEMINI.md (Gemini CLI) already holds the managed block. Their SessionEnd hooks queue the ended session for auto-distillation like Claude Code's, and a Codex PreCompact hook snapshots the session. Codex asks you to trust new hooks once (/hooks in Codex). The /recall skill is also copied to ~/.agents/skills/, the shared skills folder other agents read. Cursor gets no hook: its session-start payload has no working directory. Gemini CLI loads every context file it is configured with plus their @ imports, and Codex its fallback filenames too, so the hook stays silent wherever the managed block already lives.
• Asks your history (RAG): the Ask mode in Chat gives a synthesized, cited answer over your own threads, with [thread N] citations that open the sources it used; it is saved with your chats and follow-ups continue as a normal chat. Needs an LLM engine (memory turned on in Settings > AI engine).
• Organizes into collections: star threads and attach free-form tags, then filter the list by starred or by tag.
• Chats with an in-app agent (Anthropic / OpenAI / Gemini / OpenRouter / Ollama, local or Cloud, or your logged-in Claude Code / Codex CLI with no key) that can search your own history and run shell commands with your approval; streaming, cancellable, with live model lists. Chats are saved and become searchable too.
• Carries context across tools: open any thread in any agent CLI ("Open in Claude / Codex / Gemini …", seeded with the packed transcript), resume a Claude Code / Codex thread in its native CLI, copy context, or export a thread to Obsidian (optionally AI-summarized with decisions / gotchas / TODOs).
• Links threads to commits: infers on-device which git commits a thread produced, by overlapping the files a thread discussed with git log's changed files inside the thread's time window (shared-file count = confidence). See it as a thread→commit timeline (cal commits), per-thread in the desktop UI ("Produced commits"), or via the linked_commits MCP tool.
• Snapshots agent sessions: durable, resumable checkpoints of a thread (packed transcript + carry-forward project memory) for handoff across a context-window compaction or across tools; auto-captured by a Claude Code PreCompact hook right before a context compaction, which also keeps Claude Code's compaction summary as the thread's summary. Take, list, and resume them (cal snapshot / cal snapshots / cal resume, or the snapshot_session / list_snapshots / load_snapshot MCP tools), or in the app, where a project's page lists its snapshots to read, delete, or resume in any agent CLI.
• Guards decisions: decisions can carry a rationale ("why"), and an active guard surfaces settled decisions on a topic before an agent re-litigates one (cal check " " / the check_decision MCP tool).
• Recalls before you redo: an opt-in Claude Code hook quietly injects "you may have solved this before" into the agent's context on each prompt when it strongly matches prior work (Settings → Agents → Proactive recall, off by default, signal-floored and per-session deduped).
• Mines recurring issues: surfaces the errors you keep hitting across all your tools (normalized signatures, last 180 days) so you fix the pattern, not the instance (on the Project page, or cal issues).
• Shows what it did for you: a Stats card counts, per week, the sessions that started with injected memory or a recent-sessions digest, the prompts where recall surfaced prior work, and the MCP tool calls answered (cal stats prints the same as one line). The counts are appended to ledger.jsonl next to the index ( .ledger.jsonl for any other index file, such as the dev build's index.dev.db), and once a day is over the app moves that day's counts into the index itself; neither leaves the machine. The same card shows how many indexed Claude Code sessions are still searchable after Claude Code deleted their transcripts (its cleanupPeriodDays, 30 days by default), with a reversible "Keep transcripts for a year" that sets it