Inline session fork parameters

docs/architecture.md

@@ -143,6 +143,6 @@ New behavior should attach to a documented seam; changing the shipped loop requi
 | Intercept prompts, requests, tool use, or continuation | listen on the relevant `agent/*` or `tools/*` waterfall |
 | Add UI or editor integration | drive `ctx.agents` and render from `session/event` |
 | Add durable session state | add a `SessionEventMap` member and render/replay from the log |
-| Fork a live session | use `ctx.sessions.fork({ source, boundary?, childSessionId? })` |
+| Fork a live session | use `ctx.sessions.fork(source, boundary?, childSessionId?)` |
 
 The [extension cookbook](cookbook/extension-cookbook.md) carries plugin skeletons and the feature-to-seam map; step-by-step guides cover [packages](cookbook/adding-a-package.md), [tools](cookbook/adding-a-tool.md), [LLM adapters](cookbook/adding-an-llm-adapter.md), and [vendored packages](cookbook/adding-a-vendored-package.md).

docs/cordis-catalog/services.md

@@ -161,10 +161,10 @@ enter(session: Session): () => void
 announce(session: Session): void
 get(id: SessionId): Session | undefined
 list(): Session[]
-fork(options: ForkSessionOptions): Session
+fork(source: SessionForkSource, boundary?: number, childSessionId?: SessionId): Session
 ```
 
-Source: [`packages/core/session/src/index.ts:402`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:389`](../../packages/core/session/src/index.ts)
 
 ## `ctx.subagents` — `SubagentService`
 

docs/core-data-structures/session.md

@@ -204,7 +204,7 @@ Everything else (`turn/*`, `step/*`) is structural and does not project into a m
 
 `ctx.sessions.create(id, { seed, meta })` is the low-level replay/fork primitive. For ordinary live-session forks, `SessionStore` exposes one policy API:
 
-- `fork({ source, boundary?, childSessionId? })` accepts a live `Session` object or live `SessionId`, selects source events through the inclusive `boundary` seq (default: current last event), requires the boundary event to be `turn/end`, then creates a live child session with deep-cloned seed events plus child metadata (`parentSession`, `seedLength`, and inherited `cwd`).
+- `fork(source, boundary?, childSessionId?)` accepts a live `Session` object or live `SessionId`, selects source events through the inclusive `boundary` seq (default: current last event), requires the boundary event to be `turn/end`, then creates a live child session with deep-cloned seed events plus child metadata (`parentSession`, `seedLength`, and inherited `cwd`).
 
 An explicit `boundary` lets callers fork from a previous completed turn even if the source has newer events or an open current turn. The API rejects non-`turn/end` boundaries instead of clipping silently. Broader turn-enclosure sanity stays in the existing `dsh-invariants` plugin and persistence repair path rather than being duplicated in `fork()`. `dsh-subagent-fork` keeps its completed-prefix clipping because tool-time delegation usually starts while the parent turn is open; ordinary session branching should make the requested boundary explicit.
 

docs/rfc/implemented/feature/2026-06-30-session-store-fork-api.md

@@ -17,14 +17,8 @@ The store exposes one operation:
 ```ts ignore-check
 type SessionForkSource = Session | SessionId
 
-interface ForkSessionOptions {
-  source: SessionForkSource
-  boundary?: number
-  childSessionId?: SessionId
-}
-
 class SessionStore extends Service {
-  fork(options: ForkSessionOptions): Session
+  fork(source: SessionForkSource, boundary?: number, childSessionId?: SessionId): Session
 }
 ```