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name: claude-historian description: Use before WebSearch to check if you already have the answer, when stuck on an error to find past fixes, or when entering a familiar project to recall past sessions and file changes.

Claude Historian

Search conversation history before starting fresh. You may already have the answer.

When to Use

Before WebSearch → search(query: "...", scope: "similar") or search(query: "...", scope: "conversations"). Past solutions beat web results.

Stuck on an error → search(query: "<error message>", scope: "errors"). Finds past fixes with code.

Entering a familiar project → search(scope: "sessions") for recent work. search(query: "...", scope: "plans") for past decisions.

Working on a familiar file → search(scope: "files", filepath: "src/index.ts"). Shows past changes with context.

Quick Reference

Situation	Tool Call
Error with no obvious cause	search(query: "<error>", scope: "errors")
"Have I done this before?"	search(query: "...", scope: "similar")
Working on familiar file	search(scope: "files", filepath: "...")
Need past design reasoning	search(query: "...", scope: "plans")
What did I do last session?	search(scope: "sessions")
Successful tool workflows	search(scope: "tools")
General search	search(query: "...", scope: "conversations")
Deep-dive into session	inspect(session_id: "...")
Rules, skills, CLAUDE.md	search(query: "...", scope: "config")
Task management history	search(query: "...", scope: "tasks")
Memories across sessions	search(query: "...", scope: "memories")

Key Parameters

• scope: Target your search — conversations, errors, files, plans, config, tasks, similar, sessions, tools, memories, or all (default)
• limit: Number of results (default 10)
• project: Filter by project name substring (works with conversations, sessions)
• timeframe: today, yesterday, week, month

Common Mistakes

Mistake	Fix
Going straight to WebSearch	Check historian first — past solutions are more relevant
Vague queries	Use specific terms: error messages, file paths, tool names
Using scope: "all" for errors	Use scope: "errors" — it has dedicated fix extraction
Long keyword-dump queries	Keep to 3-5 specific terms, not 10+ generic ones