luca

LUCA

Stateless query and analysis frontend over Claude session data. Canonical surface is an MCP server (luca.query_digest, luca.query_repos, luca.ask); a Claude Code plugin wraps the same tools. Reads repo-recall directly. No local store, no docker, no hooks.

Three-layer substrate: repo-recall is the authoritative store over Claude session JSONL, git log, GitHub. session-lattice (pending) maintains materialized views in embedded DuckDB, rebuilt on a refresh tick. LUCA queries those layers and turns the results into insights. Canonical framing: agentic-os-kai/docs/substrate.md.

LUCA: Last Universal Common Ancestor. luca#38.

Install

Prerequisites: macOS or Linux, Python 3.10+, uv on PATH, repo-recall running (brew install coilysiren/tap/repo-recall && brew services start coilysiren/tap/repo-recall).

As a Claude Code plugin:

claude plugin marketplace add coilysiren/luca
claude plugin install luca@coilysiren-luca
coily exec preflight

The plugin auto-registers the MCP server via .claude-plugin/plugin.json.

As a standalone MCP server (any client):

{ "mcpServers": { "luca": { "command": "uv", "args": ["run", "/path/to/luca/luca/server.py"] } } }

Use

mcporter call luca.query_digest window=7d
mcporter call luca.query_repos limit=5
mcporter call luca.ask question="what did session abc1234 do"

query_* returns one specific data type each. ask routes a natural-language question to a small dispatch table over the same data. Unrecognized questions return a message naming the patterns LUCA supports.

LUCA makes no LLM calls. The host Claude session does the open-ended reasoning over the targeted data LUCA returns.

Inside a Claude Code session, slash commands wrap the tools: /luca-inspect (Q1 digest), /luca-ask (one question), /luca-history (sweep), /tooling-luca-meta-loop (Q2 lens). From the shell, coily exec query-digest, coily exec ask -- "...", coily exec mcp-server.

Why this exists

Path count is multiplicative once fan-out is real (The Harness Is the Backend: 4 agents × 5 backends = 80 stochastic paths). LUCA turns N × M paths into something readable.

Progressive improvement across runs: the substrate accumulates value the longer it runs, where a UI session resets each time. No UI navigation required: queries deliver observations directly into the agent session. See luca#48. The two abstract questions live in docs/questions.md.

See also

• AGENTS.md - agent-facing operating rules.
• docs/FEATURES.md - inventory of what ships today.
• docs/externals.md - full external dependency list.
• .coily/coily.yaml - allowlisted commands.

Cross-reference convention from coilysiren/agentic-os#59.