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+# Proposal: Authored History Write (non-generating ledger seed)
+
+**From:** ratatoskr-dev (reference Tier-3 consumer)
+**To:** worldtree-dev (Conversation API / engine owner)
+**Status:** Draft for scoping — pre-contract (heid-panel-reviewed 2026-07-05)
+**Date:** 2026-07-05
+
+## Motivation
+
+Consumer apps need to write a turn into a session's history **as the agent**
+(or another author) *without triggering a model generation* — e.g. an authored
+opening/greeting, imported history, scripted narration. Ratatoskr's immediate
+driver is a SillyTavern-style **first-message**: a fixed authored opening that
+replaces the model-generated greeting and sets tone/tense/style by example.
+
+This **cannot** be done client-side. Worldtree assembles context server-side,
+and the current API exposes no author-role write path: `POST
+/sessions/{id}/messages`'s `role` is a *model-role* override (`role:
+"assistant"` → `404 "Unknown model role"`), and `assistant` as an *author*-role
+exists only as a read-side `/search` filter. So a model-visible authored turn
+needs engine support.
+
+## The primitive (recentered)
+
+The fundamental operation is **write a turn into the session ledger WITHOUT
+generation**. "Author" (who wrote it) is an *attribute* of that write, not the
+defining axis — so we name the operation, not the attribute:
+
+> **Authored history write** — persist a model-visible turn into a session's
+> ledger: no generation, no lived-turn side-effects by default, provenance
+> always set.
+
+The design space is two independent axes; this primitive is one cell:
+
+|                       | side-effects ON              | side-effects OFF            |
+|-----------------------|------------------------------|-----------------------------|
+| **generation ON**     | `POST /messages` (today)     | —                           |
+| **generation OFF**    | *(future: affect replay)*    | **authored history write**  |
+
+First-message = one caller: `author=assistant`, at session-create, `effects=none`.
+
+## v1 use cases (narrowed)
+
+1. **First-message / greeting** (the driver).
+2. **Append-only narrator / scripted / scene turns.**
+3. **Debug / test state injection** (ratatoskr instrumentation).
+
+## Explicitly OUT of v1 — separate future primitives (share infra, not shape)
+
+- **History import (batch)** — atomic multi-turn seed with memory/trust policy +
+  idempotency. A batch API, not a single POST.
+- **Edit / regenerate** — history *mutation* (replace / supersede / tombstone /
+  audit), not injection.
+- **Few-shot priming** — likely context-assembly config (exemplar block), not
+  fake ledger history.
+- **Arbitrary mid-history insertion** — a "rewrite-history" capability with
+  explicit invalidation semantics.
+- **Prefill / assistant-continuation** (`author` + generate) and **authored
+  tool-result turns** — noted; outside the seed-only contract.
+
+## Design decisions
+
+### 1. Side-effects — DEFAULT OFF; bounded opt-in  `[operator-locked default; opt-in surface tightened by review]`
+
+Authored writes are inert by default: no affect appraisal (no PAD update), no
+memory write, no Bifrost/tool emission. Opt-in is a **bounded enum**, not loose
+booleans:
+
+```
+effects: "none" (default) | "memory_import"
+```
+
+Synthetic affect and Bifrost emission are deliberately **not** opt-in-able here —
+replaying affect for authored content is a separate primitive (the
+generation-OFF / side-effects-ON cell). Rationale: keep this one write-API from
+becoming a cross-subsystem mutation backdoor. Load-bearing for affect/memory
+consumers — ratatoskr instruments exactly these signals.
+
+### 2. Author-role — distinct field, restricted set  `[rec]`
+
+- New field **`author`**, distinct from the model-role `role` (the collision
+  that 404s).
+- v1 roles: **`assistant`** (agent) + **`system`** (OOC / narrator). **`user` is
+  NOT injectable** on this endpoint — model-visible spoofed user input is a
+  consent / audit / abuse surface; deferred to the future import API under
+  owner/service scope.
+- Nuance for the engine owner: `author` risks doing double duty — *provenance*
+  ("who wrote it") vs *rendering-role* ("how it appears in assembled context";
+  an `assistant` turn renders as model output, a `system` turn as instruction).
+  These likely want to be separable (a rendering/turn-class vs an `authored_by`
+  provenance). Final shape is engine-owned (context assembly is yours) — but the
+  concern is ours to raise, not punt.
+
+### 3. Generation contract — seed-only, DISTINCT SUB-RESOURCE  `[position taken]`
+
+Authored writes never trigger generation. We take a position (not defer): a
+**distinct sub-resource**, e.g. `POST /sessions/{id}/history`, **not** a
+`generate:false` flag on `POST /messages`. Reasons: explicit-over-implicit
+(don't make "did generation happen?" a parameter — the same implicit-mode
+coupling that bit us with `role`); different response contract (no generation
+id, no SSE stream, no token usage); different error surface. Exact path is yours.
+
+### 4. Provenance — structured, always present  `[rec, expanded]`
+
+Not a boolean. Every authored turn carries: the **write actor** (which
+consumer/caller injected it), the **claimed author**, **injected-at vs
+claimed-original** timestamps, **trust/origin**, and **visibility** flags
+(model-visible? user-visible? memory-eligible?). Available to admin/audit APIs
+even when not rendered to the model.
+
+### 5. Positioning — append-only + create-time (v1)  `[revised: was arbitrary insertion]`
+
+v1 supports **create-time seed and append-to-tail only**. Arbitrary mid-history
+insertion is deferred: it breaks turn-numbering, stales existing embeddings,
+desyncs the affect timeline, and races in-flight generation — a separate future
+"rewrite-history" capability with explicit invalidation semantics.
+
+## Event / lifecycle contract — positions we take (consumer contracts we validate)
+
+- **Default-off authored seed emits NO `turn.started` / `done` and NO Bifrost
+  appraisal wire.** Stated explicitly so instrumented consumers (us) don't read
+  silence as failure.
+- **Authored turns get a distinct lifecycle phase** — propose **`seeded`** (or
+  `authored`), NOT `completed` (which implies generation ran). Consumers
+  filter/display by phase.
+- **Idempotency keys required** on authored writes (retries must not duplicate
+  turns).
+- **In-progress generation** — authored writes are rejected or serialized while
+  a session has an active generation (ordering safety).
+
+## Inherent property (documented, not a bug)
+
+**Indirect affect contamination.** Even with `effects:none`, the *next generated
+turn is appraised in the context of* the authored turn — so an emotionally
+charged authored beat perturbs affect regardless of any flag. No flag prevents
+it; it is inherent. Consumers (ratatoskr especially, as the affect instrument)
+must not misattribute the resulting drift.
+
+## Genuinely engine-owned open questions
+
+- Exact endpoint path + field / enum names.
+- **Model-visible provenance in assembled context** — an engine-consistency call
+  *and a security one*: an authored `system` / `user` turn indistinguishable
+  from real input is a spoofing vector. Framed as security, not just rendering.
+- `memory_import` semantics when the future import API opts in (embedding,
+  origin/trust tagging, retrieval ranking vs lived memory).
+- Auth/scope: we assume **owner-only for v1**; per-author-role restrictions
+  (esp. `system`) TBD — confirm or correct.
+
+## Ratatoskr as reference consumer
+
+First consumer: first-message (`author=assistant`, create-time, `effects:none`)
+in the web surface + debug seed in the CLI. We commit to validating the
+primitive — including the event-silence contract and the `seeded` phase —
+end-to-end against the reference planes.
+
+---
+
+*This brief was cold-read-pressure-tested by a cross-frontier panel (Grok /
+Codex / GLM) before handoff; the v1 narrowing (append-only, bounded `effects`
+enum, edit/regenerate + import split out) and the positions-taken (sub-resource,
+event-silence, `seeded` phase, structured provenance, `user`-author restriction)
+are the triaged result.*