diff --git a/packages/experimental/claude-code-mods/src/host-ops.ts b/packages/experimental/claude-code-mods/src/host-ops.ts
index 894f9a9312..e4e7da0b61 100644
--- a/packages/experimental/claude-code-mods/src/host-ops.ts
+++ b/packages/experimental/claude-code-mods/src/host-ops.ts
@@ -293,9 +293,9 @@ export function createHostOps(options: HostOpsOptions): OpTable<AgentBinding> {
         description,
         parameters: inputSchema,
         output: {
-          // The answering hook's text, already rendered as content blocks.
-          schema: { type: 'array' },
-          render: (_args, value) => value as unknown as ContentBlock[],
+          // The answering hook's result text.
+          schema: { type: 'string' },
+          render: (_args, value) => [{ type: 'text', text: String(value) }],
         },
         execute() {
           return Promise.reject(new Error(`${mod.name} registered ${fullName} but no tool.call hook answered it; add on('tool.call', { tool: '${fullName}' }, hook)`))
diff --git a/packages/experimental/claude-code-mods/src/index.ts b/packages/experimental/claude-code-mods/src/index.ts
index abbf5d8931..52b0b99466 100644
--- a/packages/experimental/claude-code-mods/src/index.ts
+++ b/packages/experimental/claude-code-mods/src/index.ts
@@ -17,7 +17,6 @@ import { createUserMessage } from '@deepseek-ai/dsh-llm'
 import type { AssistantMessage, ContentBlock, ContextFormed, TokenUsage } from '@deepseek-ai/dsh-llm'
 import type { UserMessage } from '@deepseek-ai/dsh-session'
 import type { PostToolDecision, ToolExecutionResult, ToolExecutionToken } from '@deepseek-ai/dsh-tools'
-import type { JsonValue } from '@deepseek-ai/dsh-util-values'
 import { ModsEngine } from './engine.ts'
 import { createHostOps, toolCallResultOf } from './host-ops.ts'
 import type { AgentBinding } from './host-ops.ts'
@@ -307,8 +306,7 @@ export async function apply(ctx: Context, config: Config): Promise<void> {
       return beneath
     }
     if (modTools.has(exec.name) && answer.isError !== true) {
-      const content: ContentBlock[] = [{ type: 'text', text }]
-      return { isError: false, value: content as unknown as JsonValue, content }
+      return { isError: false, value: text, content: [{ type: 'text', text }] }
     }
     // A built-in tool's success value must satisfy its own output schema, so a
     // mod's answer in its place is reported as an error-shaped result.
diff --git a/packages/experimental/claude-code-mods/src/manifest.ts b/packages/experimental/claude-code-mods/src/manifest.ts
index 46e5a4a2be..472cba3aee 100644
--- a/packages/experimental/claude-code-mods/src/manifest.ts
+++ b/packages/experimental/claude-code-mods/src/manifest.ts
@@ -124,7 +124,8 @@ function readJson(path: string): unknown {
     throw new Error(`${path}: cannot read: ${messageOf(error)}`)
   }
   try {
-    return JSON.parse(text) as unknown
+    const parsed: unknown = JSON.parse(text)
+    return parsed
   } catch (error: unknown) {
     throw new Error(`${path}: invalid JSON: ${messageOf(error)}`)
   }
diff --git a/packages/experimental/claude-code-mods/tests/chain.spec.ts b/packages/experimental/claude-code-mods/tests/chain.spec.ts
index 8b37603988..25387aab18 100644
--- a/packages/experimental/claude-code-mods/tests/chain.spec.ts
+++ b/packages/experimental/claude-code-mods/tests/chain.spec.ts
@@ -1,6 +1,7 @@
 import { describe, expect, it, vi } from 'vitest'
 import { BudgetClock, dispatch, ENGINE_ORIGIN, HookTimeoutError } from '../src/chain.ts'
 import type { DispatchRequest, LoadedMod, RegisteredHook } from '../src/chain.ts'
+import { createModsApi } from '../src/api.ts'
 import type { AnyHook, HookMatcher, ModsApi } from '../src/types.ts'
 
 const mod = (name: string, order = 0): LoadedMod => ({ name, version: undefined, root: '/mods/' + name, modulePath: '', options: {}, order })
@@ -212,17 +213,16 @@ describe('dispatch: failures', () => {
       core: () => new Promise((resolve) => { setTimeout(() => { resolve({ result: 'slow core' }) }, 60) }),
       report,
       budgetMs: 25,
-      api: (_hook, clock) => ({
-        clock: {
-          async sleepOutside(ms: number) {
-            clock.pause()
-            await new Promise(resolve => setTimeout(resolve, ms))
-            clock.resume()
-          },
-        },
-      }) as unknown as ModsApi,
+      // A real `$` whose every call takes 60 ms to answer: the clock pauses for the call.
+      api: (hooked, clock) => createModsApi({
+        mod: hooked.mod,
+        clock,
+        invoke: () => new Promise((resolve) => { setTimeout(() => { resolve('contents') }, 60) }),
+        timers: { after: () => ({ cancel() {} }), every: () => ({ cancel() {} }) },
+        report: () => {},
+      }),
       hooks: [hook(a, 'tool.call', async ($, e, next) => {
-        await ($ as unknown as { clock: { sleepOutside(ms: number): Promise<void> } }).clock.sleepOutside(60)
+        expect(await $.fs.read('notes.md')).toBe('contents')
         return next(e)
       })],
     }))
diff --git a/packages/experimental/claude-code-mods/tests/host-ops.spec.ts b/packages/experimental/claude-code-mods/tests/host-ops.spec.ts
index ec7d4a13e1..845a12d4ca 100644
--- a/packages/experimental/claude-code-mods/tests/host-ops.spec.ts
+++ b/packages/experimental/claude-code-mods/tests/host-ops.spec.ts
@@ -4,6 +4,7 @@ import { join } from 'node:path'
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import { Context } from '@deepseek-ai/cordis'
 import type { Agent } from '@deepseek-ai/dsh-agent'
+import type { Message } from '@deepseek-ai/dsh-llm'
 import { mountAgentLoopTestDependencies } from '@deepseek-ai/dsh-agent-loop-testkit'
 import CommandRuntime from '@deepseek-ai/dsh-commands'
 import LocalFileSystem from '@deepseek-ai/dsh-fs-local'
@@ -44,9 +45,22 @@ function setup(ctx = new Context()) {
   return { ctx, ops, engine, context, call, registrations }
 }
 
+/** The members of an Agent the host ops read; a real Agent is assignable to it, which is what the assertion below relies on. */
+interface AgentFacts {
+  readonly id: string
+  readonly ctx: Context
+  readonly options: { readonly model?: string }
+  readonly session: {
+    readonly id: string
+    readonly header: { readonly id: string; readonly createdAt: number; readonly cwd?: string }
+    requestHeader(): { readonly config: { readonly provider: string; readonly model: string } } | undefined
+    deriveMessages(): Message[]
+  }
+}
+
 /** A fake agent with the session facts the ops read; its scoped ctx is the root ctx. */
 function fakeAgent(ctx: Context, overrides: { cwd?: string; model?: string; requestModel?: string } = {}): Agent {
-  return {
+  const facts: AgentFacts = {
     id: 'fake',
     ctx,
     options: overrides.model === undefined ? {} : { model: overrides.model },
@@ -54,9 +68,10 @@ function fakeAgent(ctx: Context, overrides: { cwd?: string; model?: string; requ
       id: 'fake',
       header: { id: 'fake', createdAt: 1, ...overrides.cwd === undefined ? {} : { cwd: overrides.cwd } },
       requestHeader: () => overrides.requestModel === undefined ? undefined : { config: { provider: 'p', model: overrides.requestModel } },
-      deriveMessages: () => [],
+      deriveMessages: (): Message[] => [],
     },
-  } as unknown as Agent
+  }
+  return facts as Agent
 }
 
 describe('values', () => {
diff --git a/packages/experimental/claude-code-mods/tests/loader-composition.spec.ts b/packages/experimental/claude-code-mods/tests/loader-composition.spec.ts
index b7ec708d00..9e3705ea1b 100644
--- a/packages/experimental/claude-code-mods/tests/loader-composition.spec.ts
+++ b/packages/experimental/claude-code-mods/tests/loader-composition.spec.ts
@@ -56,13 +56,9 @@ it('loads from cordis.yml, counts the model\'s tool calls, and answers /tally th
   context.baseUrl = pathToFileURL(root).href + '/'
   await context.plugin(Loader)
   context.loader.builtins.include = Include
-  context.loader.internal = {
-    version: 'v2',
-    async import(specifier: string) {
-      if (!modules.has(specifier)) throw new Error(`Unexpected fixture module: ${specifier}`)
-      return modules.get(specifier)
-    },
-  } as unknown as NonNullable<typeof context.loader.internal>
+  // Without a Node internal loader the Loader imports bare names through this
+  // test runner's module graph, which resolves workspace packages to `src`.
+  context.loader.internal = undefined
   await context.loader.create({ name: 'cordis:include', config: { path: pathToFileURL(configPath).href } })
   await context.loader.await()
   for (const entry of context.loader.entries()) await entry.fiber?.await()
diff --git a/packages/experimental/claude-code-mods/tests/module.spec.ts b/packages/experimental/claude-code-mods/tests/module.spec.ts
index 5f2ed0d257..c66388fa6d 100644
--- a/packages/experimental/claude-code-mods/tests/module.spec.ts
+++ b/packages/experimental/claude-code-mods/tests/module.spec.ts
@@ -4,7 +4,7 @@ import type { LoadedMod } from '../src/chain.ts'
 import { ModsEngine, OpDenied } from '../src/engine.ts'
 import { readModManifest } from '../src/manifest.ts'
 import { createOn, HookRegistry, loadHooksModule } from '../src/module.ts'
-import type { AnyHook, ModsApi } from '../src/types.ts'
+import type { AnyHook, HookRegistration, ModsApi } from '../src/types.ts'
 
 const FIXTURES = resolve(import.meta.dirname, 'fixtures')
 const mod = (name: string, order = 0): LoadedMod => ({ name, version: undefined, root: '/mods/' + name, modulePath: '', options: {}, order })
@@ -25,15 +25,18 @@ describe('createOn', () => {
 
   it('refuses what claude plugin validate refuses', () => {
     const { on } = createOn(mod('a'))
+    // A JavaScript mod can pass anything, so the checks are exercised through an untyped call.
+    const loose = on as (...args: unknown[]) => HookRegistration
     expect(() => on('tool.call', noop)).not.toThrow()
-    expect(() => on(42 as unknown as string, noop)).toThrow(/not a string literal/)
+    expect(() => loose(42, noop)).toThrow(/not a string literal/)
     expect(() => on('tool.calls', noop)).toThrow(/"tool.calls" is not an event/)
     expect(() => on('session.start', noop)).not.toThrow()
     expect(() => on('session.start', noop)).toThrow(/on\("session.start"\) is registered twice without a matcher/)
     expect(() => on('session.start', { cwd: '/x' }, noop)).not.toThrow()
-    expect(() => on('turn.start', 'nope' as unknown as AnyHook)).toThrow(/needs a hook function/)
-    expect(() => on('turn.start', 'nope' as unknown as Record<string, string>, noop)).toThrow(/matcher must be an object/)
-    expect(() => { on('turn.complete', noop).catch('nope' as unknown as AnyHook) }).toThrow(/needs a handler function/)
+    expect(() => loose('turn.start', 'nope')).toThrow(/needs a hook function/)
+    expect(() => loose('turn.start', 'nope', noop)).toThrow(/matcher must be an object/)
+    const attach = on('turn.complete', noop).catch as (handler: unknown) => void
+    expect(() => { attach('nope') }).toThrow(/needs a handler function/)
   })
 })
 
@@ -103,7 +106,8 @@ describe('ModsEngine', () => {
     expect(await second.state.get(ref)).toEqual({ value: undefined })
     e.forgetState('s1')
     expect(await first.state.get(ref)).toEqual({ value: undefined })
-    await expect(first.state.get({ plugin: 1 as unknown as string, key: 'x' })).rejects.toThrow(/needs \{ plugin, key \} strings/)
+    await expect(e.invoke(owner, 'state.get', { plugin: 1, key: 'x' }, { key: 's1' }, new AbortController().signal))
+      .rejects.toThrow(/needs \{ plugin, key \} strings/)
     const before = Date.now()
     expect(await first.clock.now()).toBeGreaterThanOrEqual(before)
     await first.clock.sleep(1)