---
name: obelisk
description: >
  Search and query past Claude Code session history.
  Reactive: when the user asks "how did I fix X", "what did we do last time", "find the session where", "上次怎么修的", "之前的session", "历史记录".
  Proactive: when the user references past work you lack context for, when you're about to modify a file with complex edit history, when the user says "继续之前的" or "continue where we left off", or when understanding prior decisions would improve your current response.
allowed-tools:
  - Read
  - Bash(node:*)
  - Write
---

# obelisk

Search and query Claude Code session history stored in `~/.claude/`.
Obelisk indexes sessions, messages, tool calls, tool results, summaries,
subagents, workflows, workflow agents, parent chains, and raw JSONL lines into
SQLite + FTS5.

Obelisk is a CodeAct memory layer: write a small JS query, run it locally, read
the JSON, then answer. Do not turn history into a flat document or browse entire
sessions by default.

## Quick Start

The skill directory is provided as `$SKILL_DIR` at invocation time.

Fast keyword search:

```bash
node $SKILL_DIR/scripts/runtime.mjs --search "keyword"
```

Custom query:

1. Write a bounded JS query to a temp file, for example `/tmp/q.mjs`.
2. Run:

   ```bash
   node $SKILL_DIR/scripts/runtime.mjs --query /tmp/q.mjs
   ```

3. Parse JSON stdout and answer with concise evidence.

The query file runs inside `(async () => { ... })()`. Use `return` to emit JSON.

## Query Routing

Before writing a query, classify the task. Progressive disclosure is useful, but
skipping the relevant reference usually costs extra query rounds.

- Read `references/schema.md` before raw `sql()` unless the needed table/column relationship is already explicit here. Do this before running the SQL, not after a missing-column error.
- Read `references/retrieval-semantics.md` before multi-step retrieval, scoped project/file/session searches, or synthesis/conclusion/history questions. It defines the query design frame.
- Read `references/query-patterns.md` when you need copyable query scripts: one-shot synthesis, learned detail passes, workflow trees, failure groups, file history, summaries, subagents, raw windows, or empty results.
- Read `references/pitfalls.md` after an error or when helper fields, FTS syntax, aliases, or row shapes are unclear.

If a helper row shape is unclear, first run a tiny scoped query and return
`Object.keys(row)` or a compact sample. Do not invent field names.

## Core API

### `search(text, opts?)`

Full-text search across main messages, subagent messages, and workflow-agent
messages.

Returns:

```js
[{ message: { uuid, text, role, timestamp, model, cwd },
   session: { id, title, project, started_at },
   rank,
   context }]
```

`context` here means temporal neighbors: nearby messages in the same session by
timestamp. It is not the parent chain. Use `context(uuid)` or `trace(uuid)` for
causal/parent-chain context.

Opts: `{ limit, sessionId, project, after, before, cwd }`.

`project` is a SQL `LIKE` filter over `sessions.project`, not an exact project
identity. Results are already ordered by FTS5 rank; lower rank sorts earlier.
Prefer returned order over manually interpreting numeric rank unless you are
deliberately using FTS5 semantics.

### `context(uuid)`

Returns the full story around one indexed message:

```js
{ message, parentChain, session, subagent, workflow }
```

Use this after `search()` finds a promising message. It is the usual way to
expand vertically from one evidence point without dumping the whole session.

### `sql(query, ...params)`

Raw SQL with `?` placeholders. Returns array rows.

Before writing non-trivial SQL, read `references/schema.md`. Common safe joins:

- `tool_calls` does not have timestamps. Join `messages m ON m.uuid = tc.message_uuid`.
- `tool_results` does not have timestamps. Join `messages m ON m.uuid = tr.message_uuid`.
- For project/session filters, join `sessions s ON s.id = <table>.session_id`.
- Prefer SQL-side `GROUP BY`, `COUNT`, `MAX`, `ORDER BY`, and `LIMIT` over hand-counting in the final answer.

Tables: `sessions`, `messages`, `tool_calls`, `tool_results`, `summaries`,
`subagents`, `workflows`, `workflow_agents`, `messages_fts`.

## Structured Helpers

These helpers are convenience accessors over the same SQLite structure. They do
not replace `sql()`; use `sql()` when you need an exact aggregation or a join
the helper does not expose.

All list helpers accept a bounded `limit`. Many also accept:
`{ project, after, before, sessionId, sessions, branch }`. Check the schema or a
tiny sample before relying on less common filters.

- `sessions(opts?)` -- session rows, newest first. `project` is a SQL `LIKE` pattern.
- `recent(n?)` -- shorthand for recent sessions.
- `summaries(opts?)` -- summary rows, newest first: `{ id, session_id, timestamp, source, content, session_title, project }`.
- `subagents(opts?)` -- subagent metadata plus `messageCount`.
- `workflows(opts?)` -- workflow runs, newest first.
- `workflowTree(runId)` -- workflow row plus parsed `result` and `agents`; may include bulky `script` and `result_json`, so project compact fields.
- `fileHistory(filePath, opts?)` -- Read/Edit/Write tool calls for a file, oldest first; includes many `Read` rows.
- `failures(opts?)` -- failed tool results with tool/session context, newest first.
- `trace(uuid)` -- parent chain from root to message.
- `thread(sessionId)` -- full session messages; last resort only.
- `raw(uuid, opts?)` -- windowed access to the original JSONL line.

## Retrieval Contract

Keep queries scoped, bounded, and structural.

- Scope First: classify the locator as scope, artifact, or semantic. Use the narrowest structural locator before FTS; empty scoped results are valid unless the user asks to broaden.
- Plan Before Probe: for conclusion, broad history, failure investigation, or file evolution, write a bounded retrieval script instead of spending turns on intermediate results.
- Structure Before Text: compute counts, joins, grouping, dedupe, and projection in SQL or JS; keep runtime JSON compact, ideally under 10k-12k chars for synthesis tasks.
- Evidence Before Conclusion: return compact evidence with stable IDs (`session_id`, `uuid`, `tool_call_id`, `run_id`, `agent_id`) and short snippets, then synthesize in the final answer.

If field, context, ordering, FTS, or helper semantics affect the query, read
`references/retrieval-semantics.md` before coding. If a query errors, read
`references/pitfalls.md` before retrying.

## Minimal Patterns

Search, then expand one promising hit:

```js
const hits = search('auth fix', { limit: 5 });
if (!hits.length) return [];
return hits.slice(0, 3).map(h => ({
  session_id: h.session.id,
  session_title: h.session.title,
  uuid: h.message.uuid,
  snippet: h.message.text?.slice(0, 240),
}));
```

Check helper fields before assuming names:

```js
const rows = summaries({ project: '%quiet-zero%', limit: 1 });
return rows.length ? Object.keys(rows[0]) : [];
```

Fetch message neighbors without a full thread:

```js
const hit = search('runtime query', { limit: 1 })[0];
return sql(
  `SELECT uuid, role, timestamp, substr(text,1,240) AS snippet
   FROM messages
   WHERE session_id=? AND timestamp>=?
   ORDER BY timestamp LIMIT 6`,
  hit.session.id,
  hit.message.timestamp
);
```

See `references/query-patterns.md` for longer recipes.

## Notes

- First run builds the index. Later runs update incrementally.
- DB location: `~/.claude/obelisk.sqlite`.
- Query scripts run in a sandboxed VM with no filesystem or network access from inside the script.
- Indexed text and stored tool inputs/results are truncated to 10k chars. Use `raw(uuid, { offset, limit })` for specific JSONL windows.