refactor agent pre-step inbox lifecycle

packages/hooks/hooks-codex/src/index.ts

@@ -15,7 +15,7 @@
 import { readFileSync } from 'node:fs'
 import type { Context } from 'cordis'
 import z from 'schemastery'
-import type { Agent, PromptDecision } from '@deepseek-ai/dsh-agent'
+import type { Agent, PreStepDecision } from '@deepseek-ai/dsh-agent'
 import { createUserMessage } from '@deepseek-ai/dsh-llm'
 import type { ContentBlock, MessageSource } from '@deepseek-ai/dsh-llm'
 import type { UserMessage } from '@deepseek-ai/dsh-session'
@@ -182,11 +182,6 @@ export function apply(ctx: Context, config: Config): void {
     return [ours, ...theirs ?? []]
   }
 
-  /** Append hook context to an admitted inbox batch. */
-  function appendPromptContext(theirs: UserMessage[], ours: UserMessage): UserMessage[] {
-    return [...theirs, ours]
-  }
-
   // SessionStart injects plain stdout when its detached hook resolves; a slow
   // hook may miss the first request.
   // TODO(session-start-gating): add a startup gate before promising first-turn delivery.
@@ -200,30 +195,27 @@ export function apply(ctx: Context, config: Config): void {
     /* jscpd:ignore-end */
   })
 
-  // UserPromptSubmit → PromptDecision. Codex supports block, not allow or ask.
-  ctx.on('agent/prompt-submit', async (agent, messages, signal, next): Promise<PromptDecision> => {
+  // UserPromptSubmit → PreStepDecision. Codex supports reject, not rewrite or ask.
+  ctx.on('agent/pre-step', async (agent, messages, { turn, signal }, next): Promise<PreStepDecision> => {
+    if (messages.length === 0) return next()
     const payload = {
       ...base(ctx, agent, 'UserPromptSubmit', model),
-      turn_id: String(lastTurn(agent) + 1),
+      turn_id: String(turn),
       prompt: blocksToText(messages.flatMap(message => message.content)),
     }
     const merged = await runPoint('UserPromptSubmit', '', payload, { agent, plainStdoutAsContext: true, signal })
     /* jscpd:ignore-start */
     if (merged.decision === 'deny') {
-      return {
-        kind: 'block',
-        reason: merged.reason ?? 'blocked by UserPromptSubmit hook',
-        discardClaimed: true,
-      }
+      return { kind: 'reject' }
     }
-    // Context alone is not a veto: DELEGATE so a later prompt-submit listener can
-    // still block/rewrite, then fold our context onto its decision.
+    // Context alone is not a veto: DELEGATE so a later pre-step listener can
+    // still reject/rewrite, then fold our context onto its decision.
     const downstream = await next()
     const ours = contextFrom(merged)
-    if (!ours || downstream.kind !== 'allow') return downstream
+    if (!ours || downstream.kind !== 'enter') return downstream
     return {
-      kind: 'allow',
-      messages: appendPromptContext(downstream.messages, ours),
+      kind: 'enter',
+      messages: [...downstream.messages, ours],
     }
   })