test(todo): pin configurable policy boundaries

packages/todo/tool-todo/package.json

@@ -44,6 +44,8 @@
     "cordis": "^4.0.0-rc.7"
   },
   "devDependencies": {
+    "@cordisjs/plugin-include": "workspace:^",
+    "@cordisjs/plugin-loader": "workspace:^",
     "@deepseek-ai/dsh-agent": "workspace:^",
     "@deepseek-ai/dsh-agent-loop": "workspace:^",
     "@deepseek-ai/dsh-agent-loop-testkit": "workspace:^",

packages/todo/tool-todo/tests/invariant.spec.ts

@@ -1,6 +1,8 @@
 import { describe, expect, it } from 'vitest'
 import { Context } from 'cordis'
 import SessionStore, { type Session, type SessionEvent } from '@deepseek-ai/dsh-session'
+import ToolRegistry from '@deepseek-ai/dsh-tools'
+import * as ToolTodo from '@deepseek-ai/dsh-tool-todo'
 import * as TodoInvariant from '@deepseek-ai/dsh-tool-todo/invariant'
 import InvariantService from '@deepseek-ai/dsh-invariants'
 
@@ -17,14 +19,22 @@ function event(todos: unknown): SessionEvent {
 }
 
 describe('todo snapshot invariants', () => {
-  it('accepts a unique whole-list snapshot, including several active items', async () => {
-    const ctx = await setup()
-    expect(() => { ctx.emit('session/event', {} as Session, event([
+  it('accepts historical and live parallel snapshots under the single-active tool policy', async () => {
+    const todos = [
       { content: 'Inspect state', status: 'completed' },
       { content: 'Apply fix', status: 'in_progress' },
       { content: 'Watch background build', status: 'in_progress' },
       { content: 'Run checks', status: 'pending' },
-    ])) }).not.toThrow()
+    ] as const
+    const ctx = new Context()
+    await ctx.plugin(SessionStore)
+    await ctx.plugin(ToolRegistry)
+    await ctx.plugin(ToolTodo, { allowParallelInProgress: false })
+    ctx.sessions.create().append('todo/write', { todos: [...todos] })
+    await ctx.plugin(InvariantService, { enabled: true })
+
+    await expect(ctx.plugin(TodoInvariant).then(() => undefined)).resolves.toBeUndefined()
+    expect(() => { ctx.emit('session/event', {} as Session, event(todos)) }).not.toThrow()
   })
 
   it.each([

packages/todo/tool-todo/tests/loader-composition.spec.ts

@@ -124,20 +124,23 @@ describe('tool-todo real Loader composition through cordis.yml', () => {
     expect(owner.session.events.findLast(e => e.type === 'todo/write')?.data.todos).toEqual(PARALLEL_TODOS)
   }, 30_000)
 
-  it('fails loading when allowParallelInProgress is omitted', async () => {
+  it.each([
+    { label: 'is omitted', configLines: [], failure: '$.allowParallelInProgress missing required value' },
+    { label: 'is not boolean', configLines: ['    allowParallelInProgress: "no"'], failure: '$.allowParallelInProgress' },
+  ])('fails loading when allowParallelInProgress $label', async ({ configLines, failure }) => {
     // loader.await() is all-settled; configuration failure leaves a FAILED
     // entry and escapes as a late rejection for the host boot to report.
     const rejections: unknown[] = []
     const onUnhandled = (err: unknown): void => { rejections.push(err) }
     process.on('unhandledRejection', onUnhandled)
     try {
-      const ctx = await boot([])
+      const ctx = await boot(configLines)
       const entry = [...ctx.loader.entries()].find(e => e.options.name === '@deepseek-ai/dsh-tool-todo')
       expect(entry?.fiber?.state).toBe(FiberState.FAILED)
       for (let i = 0; i < 100 && rejections.length === 0; i++) {
         await new Promise(resolve => setTimeout(resolve, 10))
       }
-      expect(rejections.map(String).join('\n')).toContain('$.allowParallelInProgress missing required value')
+      expect(rejections.map(String).join('\n')).toContain(failure)
     } finally {
       process.off('unhandledRejection', onUnhandled)
     }