agentic-sx Phase 1: schema — typed agentic objects over sx-git store (TDD)

Type registry (briefing / console-trace / behaviour TAG / agent-commit +
spawn/finding/refactor/test/session-merge/decision subtypes) with reflexive
transitive is-a? and create-only register-type!. Agent commits ARE git
commits (:agent-type rides as an open field, participates in the CID, DAG
machinery applies unchanged). 65/65.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

lib/agentic/schema.sx

@@ -0,0 +1,160 @@
+; lib/agentic/schema.sx — agentic-sx Phase 1: the object types.
+; An agentic structure IS the open-branch set of a repo: one branch = one
+; agent, seeded by a briefing. All objects are plain SX dicts, typed by
+; :type, content-addressed via sx-git's native CID (git/cid, git/write) —
+; same store, same identity rules as blob/tree/commit/tag.
+;
+; Two families:
+;   object types  — standalone: briefing, console-trace, behaviour (TAG only,
+;                   library HELD Phase 8). :type carries the type name.
+;   commit kinds  — agent-commit (extensible base) + subtypes spawn/finding/
+;                   refactor/test/session-merge/decision. These ARE git
+;                   commits (:type "commit") so the whole DAG/branch/merge
+;                   machinery applies; the kind rides in :agent-type and
+;                   participates in the CID like any extra commit field.
+;
+; Full fed-sx DefineType/SubtypeOf + federation is HELD (Phase 7) — this
+; registry declares the tags and the subtype relation locally.
+; Requires: lib/git/object.sx (and its persist/artdag deps).
+
+; ---- type registry ----
+(define agentic/types {:refactor {:parent "agent-commit" :kind "commit" :doc "behaviour-preserving restructure"} :console-trace {:parent nil :kind "object" :doc "console/tool output attached to a commit by cid"} :test {:parent "agent-commit" :kind "commit" :doc "adds or repairs tests"} :spawn {:parent "agent-commit" :kind "commit" :doc "genesis commit seeding an agent branch from a briefing"} :finding {:parent "agent-commit" :kind "commit" :doc "a discovered fact worth recording"} :briefing {:parent nil :kind "object" :doc "branch genesis — why an agent exists"} :decision {:parent "agent-commit" :kind "commit" :doc "records a choice and its rationale"} :session-merge {:parent "agent-commit" :kind "commit" :doc "merges another agent session's branch"} :agent-commit {:parent nil :kind "commit" :doc "extensible base for typed agent commits"} :behaviour {:parent nil :kind "object" :doc "behaviour TAG only — library HELD (Phase 8)"}})
+
+(define
+  agentic/type?
+  (fn (name) (and (string? name) (has-key? agentic/types name))))
+
+(define
+  agentic/type-info
+  (fn (name) (if (agentic/type? name) (get agentic/types name) nil)))
+
+(define
+  agentic/type-parent
+  (fn
+    (name)
+    (let
+      ((info (agentic/type-info name)))
+      (if (dict? info) (get info :parent) nil))))
+
+(define
+  agentic/type-kind
+  (fn
+    (name)
+    (let
+      ((info (agentic/type-info name)))
+      (if (dict? info) (get info :kind) nil))))
+
+; reflexive + transitive subtype walk, bounded against registry cycles
+(define
+  agentic/is-a-n?
+  (fn
+    (name ancestor depth)
+    (cond
+      ((<= depth 0) false)
+      ((not (agentic/type? name)) false)
+      ((= name ancestor) true)
+      (else
+        (let
+          ((p (agentic/type-parent name)))
+          (if
+            (nil? p)
+            false
+            (agentic/is-a-n? p ancestor (- depth 1))))))))
+
+(define
+  agentic/is-a?
+  (fn (name ancestor) (agentic/is-a-n? name ancestor 10)))
+
+; extend the registry (downstream: sx-gitea review kinds, behaviour library).
+; create-only; parent must exist when given. => name | nil
+(define
+  agentic/register-type!
+  (fn
+    (name parent kind doc)
+    (if
+      (and
+        (string? name)
+        (not (agentic/type? name))
+        (or (nil? parent) (agentic/type? parent)))
+      (begin (set! agentic/types (assoc agentic/types name {:parent parent :kind kind :doc doc})) name)
+      nil)))
+
+(define
+  agentic/commit-kind?
+  (fn
+    (kind)
+    (and
+      (agentic/type? kind)
+      (= (agentic/type-kind kind) "commit")
+      (agentic/is-a? kind "agent-commit"))))
+
+; all registered commit kinds (incl. the base), sorted
+(define
+  agentic/commit-kinds
+  (fn
+    ()
+    (sort (filter (fn (n) (agentic/commit-kind? n)) (keys agentic/types)))))
+
+; ---- briefing — branch genesis / "why" ----
+(define agentic/briefing (fn (title goal meta) (merge meta {:type "briefing" :title title :goal goal})))
+
+(define
+  agentic/briefing?
+  (fn (obj) (and (dict? obj) (= (get obj :type) "briefing"))))
+
+(define agentic/briefing-title (fn (obj) (get obj :title)))
+(define agentic/briefing-goal (fn (obj) (get obj :goal)))
+
+; ---- agent-commit — a git commit carrying an agentic kind ----
+; kind must be a registered commit kind; :agent-type is protected, all other
+; meta is open (:briefing :agent :message :behaviour-cid ... round-trip and
+; participate in the CID). => commit dict | nil on unknown kind
+(define
+  agentic/agent-commit
+  (fn
+    (tree-cid parents kind meta)
+    (if
+      (agentic/commit-kind? kind)
+      (git/commit tree-cid parents (merge meta {:agent-type kind}))
+      nil)))
+
+(define
+  agentic/commit-kind
+  (fn (obj) (if (dict? obj) (get obj :agent-type) nil)))
+
+(define
+  agentic/agent-commit?
+  (fn
+    (obj)
+    (and (git/commit? obj) (agentic/commit-kind? (agentic/commit-kind obj)))))
+
+; is obj an agent-commit of (a subtype of) kind?
+(define
+  agentic/kind-of?
+  (fn
+    (obj kind)
+    (and
+      (agentic/agent-commit? obj)
+      (agentic/is-a? (agentic/commit-kind obj) kind))))
+
+(define agentic/commit-briefing (fn (obj) (get obj :briefing)))
+(define agentic/commit-agent (fn (obj) (get obj :agent)))
+(define agentic/commit-behaviour (fn (obj) (get obj :behaviour-cid)))
+
+; ---- console-trace — attached to a commit by cid (binding is Phase 3) ----
+(define agentic/trace-entry (fn (kind text) {:text text :kind kind}))
+
+(define agentic/console-trace (fn (entries meta) (merge meta {:type "console-trace" :entries entries})))
+
+(define
+  agentic/console-trace?
+  (fn (obj) (and (dict? obj) (= (get obj :type) "console-trace"))))
+
+(define agentic/trace-entries (fn (obj) (get obj :entries)))
+
+; ---- behaviour — TAG declared, library HELD (Phase 8) ----
+(define agentic/behaviour (fn (name body meta) (merge meta {:name name :type "behaviour" :body body})))
+
+(define
+  agentic/behaviour?
+  (fn (obj) (and (dict? obj) (= (get obj :type) "behaviour"))))