loopd: the memory block from memoryd, recall and memory as core tools

Implemented-By: OpenCode session (model recorded in docs/implementer-log.md)

crates/loopd/src/baseline.rs

@@ -1,5 +1,5 @@
-//! The baseline: the fixed prefix of every request in an epoch — the system prompt, core memory
-//! and core tool schemas. It is snapshotted per session so an edit to `system.md` changes nothing
+//! The baseline: the fixed prefix of every request in an epoch — the system prompt, the memory
+//! block and core tool schemas. It is snapshotted per session so an edit to `system.md` changes nothing
 //! for a running session, and `messages` turns a session log back into the request's messages.
 
 use std::path::{Path, PathBuf};
@@ -25,7 +25,6 @@ pub enum BaselineError {
     Read(PathBuf, std::io::Error),
     Parse(PathBuf, serde_json::Error),
     Hash,
-    Core(PathBuf, std::io::Error),
 }
 
 impl std::fmt::Display for BaselineError {
@@ -34,11 +33,6 @@ impl std::fmt::Display for BaselineError {
             BaselineError::Read(path, err) => write!(f, "{}: {err}", path.display()),
             BaselineError::Parse(path, err) => write!(f, "{}: {err}", path.display()),
             BaselineError::Hash => write!(f, "hashing the baseline failed"),
-            BaselineError::Core(path, err) => write!(
-                f,
-                "{}: {err}; see docs/runbook.md#core-memory-unreadable",
-                path.display()
-            ),
         }
     }
 }
@@ -46,29 +40,26 @@ impl std::fmt::Display for BaselineError {
 impl std::error::Error for BaselineError {}
 
 impl Baseline {
-    /// The system prompt trimmed, plus core memory if it has content; the core tool schemas.
+    /// The system prompt trimmed, with no memory: for tests and the self-test.
     pub fn assemble(cfg: &Config, registry: &Registry) -> Result<Baseline, BaselineError> {
+        Baseline::assemble_with(cfg, registry, "")
+    }
+
+    /// The system prompt trimmed, then a blank line and the memory block `memoryd` rendered (M5a
+    /// spec, section 4), when there is one; the core tool schemas.
+    pub fn assemble_with(
+        cfg: &Config,
+        registry: &Registry,
+        memory: &str,
+    ) -> Result<Baseline, BaselineError> {
         let system = std::fs::read_to_string(&cfg.baseline.system)
             .map_err(|e| BaselineError::Read(cfg.baseline.system.clone(), e))?;
         let mut system = system.trim_end().to_string();
-
-        let core = cfg.paths.home.join("memory/core.md");
-        match std::fs::read_to_string(&core) {
-            Ok(text) => {
-                let trimmed = text.trim();
-                if !trimmed.is_empty() {
-                    system.push_str("\n\n");
-                    system.push_str(trimmed);
-                }
-            }
-            // A missing file is fine; an unreadable one is reported so the owner is not given a
-            // session without the memory they curated and no sign of it.
-            Err(e) if e.kind() != std::io::ErrorKind::NotFound => {
-                return Err(BaselineError::Core(core.clone(), e));
-            }
-            Err(_) => {}
+        let memory = memory.trim();
+        if !memory.is_empty() {
+            system.push_str("\n\n");
+            system.push_str(memory);
         }
-
         Ok(Baseline {
             system,
             tools: registry.core_schemas(),