claude-historian
// Automatic history search — checks past sessions before web research, planning, and debugging, siblings deepen coverage
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stars:290
forks:55
updated:February 22, 2026
SKILL.mdreadonly
SKILL.md Frontmatter
nameclaude-historian
descriptionAutomatic history search — checks past sessions before web research, planning, and debugging, siblings deepen coverage
triggersPreToolUse,PostToolUse
Historian Plugin
Session memory. Checks past sessions before redundant research, planning, or debugging.
Hooks
| Hook | When | Action |
|---|---|---|
| PreToolUse(WebSearch/WebFetch) | Before web research | Checks find_similar_queries() first |
| PreToolUse(EnterPlanMode) | Before planning | Searches search_plans() for past approaches |
| PreToolUse(Task) | Before agents | Checks find_tool_patterns() for workflows |
| PostToolUse(Bash) | After errors | Suggests get_error_solutions() |
Commands
| Command | Description |
|---|---|
/search-historian <query> | Search past sessions for solutions, decisions, context |
Workflows
Search (standalone)
search_conversations("query")— full-text across all sessions- If error-related:
get_error_solutions("error pattern") - If file-related:
find_file_context("filename") - Summarize relevant findings
Search (with siblings)
search_conversations("query")— historian's own search- If praetorian active:
praetorian_restore("query")for compacted context (denser than raw history) - If oracle active:
search("query")when error patterns suggest a missing tool - Combine: historian provides breadth (all sessions), praetorian provides depth (curated insights)
Error Resolution (standalone)
get_error_solutions("error pattern")— how was this fixed before?- If found: apply the previous solution
- If not: proceed with normal debugging
Error Resolution (with siblings)
get_error_solutions("error pattern")— historian checks past fixes- If oracle active:
search("error tool")for tools that address this error class - If gladiator active: check if this error was already observed as a pattern
- Present combined findings: past fix + available tools + pattern context
Sibling Synergy
| Sibling | Value | How |
|---|---|---|
| Praetorian | Research will be compacted after | Praetorian prompts saving after web searches historian triggers |
| Oracle | Tools found for error patterns | Oracle searches for tools when historian finds recurring errors |
| Gladiator | Observations correlate with history | Past solutions enrich gladiator reflection |
| Vigil | Checkpoints complement history | File state preserved alongside session history |
MCP Tools Reference
| Tool | Purpose |
|---|---|
search_conversations | General history search |
find_similar_queries | Find related past questions |
get_error_solutions | Find how errors were fixed |
find_file_context | Track file changes |
find_tool_patterns | Discover successful workflows |
list_recent_sessions | Browse recent work |
search_plans | Find past implementation plans |
Requires
claude mcp add historian -- npx claude-historian-mcp