diff --git a/poc-memory/src/cli/agent.rs b/poc-memory/src/cli/agent.rs
index d5f1d5f..0350830 100644
--- a/poc-memory/src/cli/agent.rs
+++ b/poc-memory/src/cli/agent.rs
@@ -4,8 +4,12 @@ use crate::store;
 use crate::agents::llm;
 
 pub fn cmd_run_agent(agent: &str, count: usize, target: &[String], query: Option<&str>, dry_run: bool, local: bool) -> Result<(), String> {
+    // Mark as agent so tool calls (e.g. poc-memory render) don't
+    // pollute the user's seen set as a side effect
+    // SAFETY: single-threaded at this point (CLI startup, before any agent work)
+    unsafe { std::env::set_var("POC_AGENT", "1"); }
+
     if dry_run {
-        // SAFETY: single-threaded at this point (CLI startup, before any agent work)
         unsafe { std::env::set_var("POC_MEMORY_DRY_RUN", "1"); }
     }
 
diff --git a/poc-memory/src/cli/node.rs b/poc-memory/src/cli/node.rs
index bb5173a..9a762cf 100644
--- a/poc-memory/src/cli/node.rs
+++ b/poc-memory/src/cli/node.rs
@@ -249,18 +249,21 @@ pub fn cmd_render(key: &[String]) -> Result<(), String> {
         .ok_or_else(|| format!("Node not found: {}", bare))?;
     print!("{}", rendered);
 
-    // Mark as seen if we're inside a Claude session
-    if let Ok(session_id) = std::env::var("POC_SESSION_ID") {
-        if !session_id.is_empty() {
-            let state_dir = std::path::PathBuf::from("/tmp/claude-memory-search");
-            let seen_path = state_dir.join(format!("seen-{}", session_id));
-            if let Ok(mut f) = std::fs::OpenOptions::new()
-                .create(true).append(true).open(seen_path)
-            {
-                use std::io::Write;
-                let ts = chrono::Local::now().format("%Y-%m-%dT%H:%M:%S");
-                let _ = writeln!(f, "{}\t{}", ts, bare);
-            }
+    // Mark as seen if we're inside a Claude session (not an agent subprocess —
+    // agents read the seen set but shouldn't write to it as a side effect of
+    // tool calls; only surface_agent_cycle should mark keys seen)
+    if std::env::var("POC_AGENT").is_err()
+        && let Ok(session_id) = std::env::var("POC_SESSION_ID")
+        && !session_id.is_empty()
+    {
+        let state_dir = std::path::PathBuf::from("/tmp/claude-memory-search");
+        let seen_path = state_dir.join(format!("seen-{}", session_id));
+        if let Ok(mut f) = std::fs::OpenOptions::new()
+            .create(true).append(true).open(seen_path)
+        {
+            use std::io::Write;
+            let ts = chrono::Local::now().format("%Y-%m-%dT%H:%M:%S");
+            let _ = writeln!(f, "{}\t{}", ts, bare);
         }
     }