diff --git a/src/inject.rs b/src/inject.rs
index 9a7281f..b132c61 100644
--- a/src/inject.rs
+++ b/src/inject.rs
@@ -1,7 +1,7 @@
 use crate::report::format_tokens;
 use crate::types::Report;
 use std::fs;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 
 struct Rule {
     category: &'static str,
@@ -107,12 +107,15 @@ pub fn generate_rules(report: &Report) -> String {
     lines.join("\n")
 }
 
-pub fn inject_rules(report: &Report) {
+pub fn inject_rules(report: &Report, claude_base: Option<&Path>) {
     let rules_content = generate_rules(report);
 
-    let claude_dir = dirs::home_dir()
-        .unwrap_or_else(|| PathBuf::from("."))
-        .join(".claude");
+    let claude_dir = match claude_base {
+        Some(base) => base.to_path_buf(),
+        None => dirs::home_dir()
+            .unwrap_or_else(|| PathBuf::from("."))
+            .join(".claude"),
+    };
 
     let rules_path = claude_dir.join("ccwasted-rules.md");
     let claude_md_path = claude_dir.join("CLAUDE.md");
diff --git a/src/main.rs b/src/main.rs
index d0691d7..6b3bd50 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -8,6 +8,7 @@ mod types;
 
 use chrono::Local;
 use clap::Parser;
+use std::path::PathBuf;
 use types::{Report, SessionInfo, SessionReport};
 
 #[derive(Parser)]
@@ -44,13 +45,18 @@ struct Cli {
     /// Filter by project directory (matches against JSONL project paths)
     #[arg(long)]
     project_dir: Option<String>,
+
+    /// Path to Claude instance directory (default: ~/.claude). Use to target ~/.claude-work, ~/.claude-personal, etc.
+    #[arg(long, short = 'C', value_hint = clap::ValueHint::DirPath)]
+    claude_dir: Option<PathBuf>,
 }
 
 fn main() {
     let cli = Cli::parse();
     let today = Local::now().date_naive();
 
-    let found = scanner::find_sessions(cli.days, cli.project_dir.as_deref());
+    let claude_dir = cli.claude_dir.as_deref();
+    let found = scanner::find_sessions(cli.days, cli.project_dir.as_deref(), claude_dir);
     if found.is_empty() {
         if cli.json {
             let empty = Report {
@@ -149,7 +155,7 @@ fn main() {
         let rules = inject::generate_rules(&report);
         println!("{}", rules);
     } else if cli.inject {
-        inject::inject_rules(&report);
+        inject::inject_rules(&report, claude_dir);
     } else if cli.json {
         json_report::print_json(&report);
     } else {
diff --git a/src/scanner.rs b/src/scanner.rs
index 1904c5c..69ce99e 100644
--- a/src/scanner.rs
+++ b/src/scanner.rs
@@ -11,12 +11,16 @@ pub struct FoundSession {
     pub project_name: String,
 }
 
-pub fn find_sessions(days: u32, project_dir: Option<&str>) -> Vec<FoundSession> {
+pub fn find_sessions(days: u32, project_dir: Option<&str>, claude_base: Option<&Path>) -> Vec<FoundSession> {
     let today = Local::now().date_naive();
     let since = today - chrono::Duration::days(days as i64 - 1);
-    let claude_dir = dirs::home_dir()
-        .unwrap_or_else(|| PathBuf::from("."))
-        .join(".claude/projects");
+    let claude_dir = match claude_base {
+        Some(base) => base.join("projects"),
+        None => dirs::home_dir()
+            .unwrap_or_else(|| PathBuf::from("."))
+            .join(".claude")
+            .join("projects"),
+    };
     if !claude_dir.exists() {
         return vec![];
     }
@@ -189,4 +193,25 @@ mod tests {
         assert!(!files.is_empty());
         assert!(files.iter().any(|f| f.path.ends_with("minimal.jsonl")));
     }
+
+    #[test]
+    fn test_find_sessions_with_custom_claude_base() {
+        let tmp = std::env::temp_dir().join("ccwasted_test_claude_base");
+        let project_dir = tmp.join("projects").join("-test-project");
+        std::fs::create_dir_all(&project_dir).unwrap();
+
+        // Copy a fixture jsonl into the fake project dir with a recent mtime
+        let src = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("tests/fixtures/minimal.jsonl");
+        let dst = project_dir.join("session-abc123.jsonl");
+        std::fs::copy(&src, &dst).unwrap();
+
+        let sessions = find_sessions(30, None, Some(&tmp));
+        std::fs::remove_dir_all(&tmp).unwrap();
+
+        assert!(!sessions.is_empty(), "should find sessions in custom claude_base");
+        assert!(
+            sessions[0].main_jsonl.starts_with(&project_dir),
+            "session path should be under the custom base, not ~/.claude"
+        );
+    }
 }