Merge master into codex/simp-session-log-representation

packages/core/session/src/index.ts

@@ -24,7 +24,6 @@ export type { JsonValue } from './json.ts'
 export { interruptedTurnClosers } from './repair.ts'
 export type { SurfaceFoldReplacement, SurfaceFoldResult } from './surface.ts'
 export { foldSurface, isSurfaceEvent, isSurfaceEligibleType } from './surface.ts'
-export { isToolPairingBalanced } from './tool-pairing.ts'
 export { canonicalHeader, foldRequestHeader, headerEquals } from './request-header.ts'
 
 declare module 'cordis' {

packages/core/session/src/tool-pairing.ts

@@ -1,56 +0,0 @@
-/**
- * Tool-pairing balance over a session surface. Compaction changes surface
- * positions, so safe cuts are derived from tool-call/result content on the
- * surface rather than step markers in the append-only log.
- * @module @deepseek-ai/dsh-session/tool-pairing
- */
-
-import type { SessionEvent } from './types.ts'
-
-/**
- * The tool-pairing delta of a surface node: how it shifts the count of
- * unanswered tool calls. An `assistant/message` opens one bracket per
- * `tool-call` block; a `tool/result` closes one; every other surface node
- * (`user/message`, `context/message`, `steering/message`, a usage-only
- * `assistant/message` with no tool-call blocks) is pairing-neutral.
- */
-function nodeDelta(event: SessionEvent): number {
-  switch (event.type) {
-    case 'assistant/message':
-      return event.data.content.filter(block => block.type === 'tool-call').length
-    case 'tool/result':
-      return -1
-    // Non-pairing surface nodes and every non-surface event contribute nothing.
-    default:
-      return 0
-  }
-}
-
-/**
- * Check that a surface cut does not split a tool call from its result. A region
- * is safe to collapse only when both edge cuts return true.
- *
- * @param nodes - surface event sequence numbers in head-to-tail order.
- * @param events - the session log indexed by those sequence numbers.
- * @param beforeSeq - event immediately after the cut; null or an absent seq means after-tail.
- * @returns whether every call before the cut is answered before it.
- * @throws if a result appears without a preceding open call.
- */
-export function isToolPairingBalanced(
-  nodes: readonly number[],
-  events: readonly SessionEvent[],
-  beforeSeq: number | null,
-): boolean {
-  let depth = 0
-  for (const seq of nodes) {
-    if (seq === beforeSeq) return depth === 0
-    // seq is a surface event sequence, always a valid log index by construction.
-    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-    depth += nodeDelta(events[seq]!)
-    if (depth < 0) {
-      throw new Error(`tool-pairing balance: tool/result at surface seq ${seq} has no matching tool-call (corrupt surface)`)
-    }
-  }
-  // A missing cut sequence means the after-tail boundary.
-  return depth === 0
-}