docs: add Contract sections + tag tests to contract items (Tier 2 — 10 files)

org/core-loop.org

@@ -33,6 +33,15 @@ The three-tier error recovery model:
 2. **Critical errors** (undefined functions, malformed data) — require memory rollback to the last snapshot
 3. **Recursive loops** (signals generating more signals indefinitely) — depth limit enforcement
 
+** Contract
+
+1. (loop-process signal): the full pipeline loop — Perceive → Reason
+   → Act. Enforces depth limit (10). Catches errors with rollback and
+   ~:loop-error~ re-injection on non-terminal errors below depth 2.
+2. (process-signal signal): thin alias for ~loop-process~.
+3. (diagnostics-startup-run): runs health check on startup, sets
+   ~*system-health*~ to ~:healthy~, ~:degraded~, or ~:unhealthy~.
+
 * Implementation
 
 ** Package Context
@@ -311,7 +320,7 @@ Verifies that the immune system (error handling) correctly catches and reports e
 (in-suite immune-suite)
 
 (test loop-error-injection
-  "Verify that a crash in think/decide triggers a :loop-error stimulus."
+  "Contract 1: a crash in think/decide triggers :loop-error stimulus."
   (clrhash passepartout::*skill-registry*)
   (passepartout:defskill :evil-skill
     :priority 100
@@ -323,7 +332,7 @@ Verifies that the immune system (error handling) correctly catches and reports e
     (is (not (null (find-if (lambda (line) (search "CRITICAL BRAIN FAILURE" line)) logs))))))
 
 (test test-process-signal-normal-path
-  "A valid signal should pass through the pipeline without error."
+  "Contract 1: a valid signal passes through the pipeline without crash."
   (clrhash passepartout::*skill-registry*)
   (handler-case
       (let ((signal (list :type :EVENT :depth 0 :payload (list :sensor :heartbeat))))
@@ -333,7 +342,7 @@ Verifies that the immune system (error handling) correctly catches and reports e
       (fail "Pipeline crashed on normal signal: ~a" c))))
 
 (test test-loop-process-returns-nil-on-deep
-  "Processing a signal at depth > 10 should return nil."
+  "Contract 1: depth > 10 returns nil from loop-process."
   (let ((result (loop-process '(:type :EVENT :depth 11 :payload (:sensor :heartbeat)))))
     (is (null result))))
 #+end_src