Surface consult session ids in saved outputs

3 files changed, 10 insertions, 3 deletions

diff --git a/assets/codex-skills/phone-opus/SKILL.md b/assets/codex-skills/phone-opus/SKILL.md
index 9a0781b..6b1ae3d 100644
--- a/assets/codex-skills/phone-opus/SKILL.md
+++ b/assets/codex-skills/phone-opus/SKILL.md
@@ -37,6 +37,7 @@ should be taken as authoritative or final. It is a pure consultant.
 - Uses `--dangerously-skip-permissions`, but wraps Claude in an external `systemd-run --user` sandbox.
 - The sandbox keeps the filesystem globally read-only, gives Claude a separate persistent home under phone-opus state, leaves `/tmp` and `/var/tmp` writable, and forces the consulted `cwd` read-only when that tree would otherwise be writable.
 - Previous consult outputs can be found in `/tmp/phone_opus-consults`.
+- For related follow-ups, strongly prefer reusing `session_id`; cold-start Opus burns quota rereading files, while session reuse is much cheaper.
 - This surface is consultative only. Edit tools are unavailable.
 - The returned `session_id` is reusable: pass it back into a later `consult` call to continue that Claude conversation.
 - Background consults return a `job_id`; use `consult_job` to poll one job or `consult_jobs` to rediscover recent ones.
diff --git a/crates/phone-opus/src/mcp/service.rs b/crates/phone-opus/src/mcp/service.rs
index 2baa744..ff25433 100644
--- a/crates/phone-opus/src/mcp/service.rs
+++ b/crates/phone-opus/src/mcp/service.rs
@@ -691,14 +691,18 @@ impl ClaudeSandbox {
 struct PersistedConsultPath(PathBuf);
 
 impl PersistedConsultPath {
-    fn new(request: &ConsultRequest) -> io::Result<Self> {
+    fn new(request: &ConsultRequest, session_id: Option<&str>) -> io::Result<Self> {
         fs::create_dir_all(CONSULT_OUTPUT_ROOT)?;
         let timestamp = OffsetDateTime::now_utc()
             .format(CONSULT_TIMESTAMP_FORMAT)
             .map_err(|error| io::Error::other(error.to_string()))?;
         let slug = consult_slug(request.prompt.as_str());
+        let session_slug = session_id.map_or_else(
+            || "session-none".to_owned(),
+            |session_id| format!("session-{}", consult_slug(session_id)),
+        );
         Ok(Self(Path::new(CONSULT_OUTPUT_ROOT).join(format!(
-            "{timestamp}-{slug}-{}.json",
+            "{timestamp}-{slug}-{session_slug}-{}.json",
             Uuid::new_v4()
         ))))
     }
@@ -1270,7 +1274,7 @@ fn persist_consult_output(
     result: &str,
     envelope: &ClaudeJsonEnvelope,
 ) -> io::Result<PersistedConsultPath> {
-    let path = PersistedConsultPath::new(request)?;
+    let path = PersistedConsultPath::new(request, envelope.session_id.as_deref())?;
     let saved_at = OffsetDateTime::now_utc()
         .format(&Rfc3339)
         .map_err(|error| io::Error::other(error.to_string()))?;
diff --git a/crates/phone-opus/tests/mcp_hardening.rs b/crates/phone-opus/tests/mcp_hardening.rs
index f7ce125..f4a8a89 100644
--- a/crates/phone-opus/tests/mcp_hardening.rs
+++ b/crates/phone-opus/tests/mcp_hardening.rs
@@ -417,6 +417,7 @@ fn consult_can_resume_a_prior_session_with_read_only_toolset_and_requested_worki
         "persisted output path",
     )?;
     assert!(persisted_output_path.starts_with("/tmp/phone_opus-consults/"));
+    assert!(persisted_output_path.contains(resumed_session));
     let persisted_output = must(
         fs::read_to_string(&persisted_output_path),
         "read persisted consult output",
@@ -644,6 +645,7 @@ fn consult_can_run_in_background_and_be_polled() -> TestResult {
         "background persisted output path",
     )?;
     assert!(persisted_output_path.starts_with("/tmp/phone_opus-consults/"));
+    assert!(persisted_output_path.contains("3fc69f58-7752-4d9d-a95d-19a217814b6a"));
     let persisted_output = must(
         fs::read_to_string(&persisted_output_path),
         "read background persisted consult output",