fix(web): correct the preset-layer contracts review found stale

None of these change behavior; each said something that was not true.

`SessionCwdConflict`'s doc block had been left stranded above the
`AgentPresetConflict` inserted under it, so one class carried a comment
about the other and the second carried none.

The roster comment named a `.system` directory that does not exist; the
shipped root is `config/agent-presets/`, and `system` is the trust its
entries carry.

The real-composition test attributed the disabled `api-gateway` row to
"side effects outside this process" alongside the port and the exporter.
It is disabled for a different reason — the api-proxy cannot mount in
this layer at all — and hiding that behind the same phrase would leave a
later layer unable to tell whether the line can come out.

One test claimed to refuse an adoption while asserting only that the
header records the preset; it now says what it checks.

`PERSONA_SECTION`/`PERSONA_ORDER` existed twice, once in the registry
that declares the slot and once restated in the row that replaces it —
a drift that would land a preset's persona beside the deployment's
instead of shadowing it. The registry exports them now.

The preset conflict message read "already runs agent preset undefined"
for a session that records none, which is the shape a deployment with no
roster produces; it names that case instead, with the regression that
reaches it through the gateway.

Finally, `PresetTree.write()` drops the `loader/config-update` the
inherited method emits — recorded on the override, since a future
edit-while-running flow needs its own persistence path.

apps/cli/tests/web-agent-presets.spec.ts

@@ -22,11 +22,17 @@ const WEB_OVERLAY = join(CONFIG_DIR, 'web.cordis.yml')
 async function bootWeb(): Promise<Context> {
   const patches: PatchOptions[] = [
     ...loadOverlayPatches('dsh-test', WEB_OVERLAY),
-    // Host rows with side effects outside this process.
+    // Host rows with side effects outside this process: a bound port, a
+    // served asset tree, a telemetry exporter.
     { id: 'webserver', disabled: true },
     { id: 'telemetry-otel', disabled: true },
     { id: 'modules', disabled: true },
     { id: 'connection', disabled: true },
+    // NOT a side-effect row: the api-proxy cannot mount in THIS layer at all,
+    // because it injects `subagents` and the subagent registry moved into the
+    // presets here. That is the breakage a later layer returns to the host
+    // plane; when it does, this line comes out and the boot audit covers the
+    // whole host-plane injection graph again.
     { id: 'api-gateway', disabled: true },
     { id: 'directory-picker', disabled: true },
     // The roster AppCLIEntry would patch in; only the shipped root, so a
@@ -134,6 +140,11 @@ describe('the shipped Web composition', () => {
       setup: agentCtx => ctx.agentPresets.mount(agentCtx, 'standard').then(() => undefined),
     })
     await handle.dispose()
+    // Slack, not a race the number has to win. The write is driven by the
+    // Loader's fiber-unload listener, which fires as the subtree's fibers
+    // settle rather than when `dispose()` resolves, and the Loader exposes no
+    // flush to await. A regression writes synchronously inside that listener,
+    // so any wait past settlement fails; a longer one only slows the test.
     await new Promise(resolve => setTimeout(resolve, 50))
 
     expect(await readFile(path, 'utf8')).toBe(before)
@@ -185,7 +196,7 @@ describe('a forked session', () => {
 })
 
 describe('a session keeps the preset it was created with', () => {
-  it('refuses to adopt a live session under a different preset', async () => {
+  it('records the preset the gateway guard reads', async () => {
     const handle = await ctx.agents.create({
       sessionId: SessionId('preset-locked'),
       meta: { agentPreset: 'core-web' },

docs/config-catalog.md

@@ -1038,7 +1038,7 @@ export interface Config {
 }
 ```
 
-Source: [`packages/preset/persona/src/index.ts:33`](../packages/preset/persona/src/index.ts)
+Source: [`packages/preset/persona/src/index.ts:34`](../packages/preset/persona/src/index.ts)
 
 ## `@deepseek-ai/dsh-plan-mode`
 
@@ -1790,7 +1790,7 @@ export interface Config {
 }
 ```
 
-Source: [`packages/core/system-prompt/src/index.ts:166`](../packages/core/system-prompt/src/index.ts)
+Source: [`packages/core/system-prompt/src/index.ts:177`](../packages/core/system-prompt/src/index.ts)
 
 ## `@deepseek-ai/dsh-time-context`
 

docs/cordis-catalog/services.md

@@ -79,9 +79,26 @@ async resolve(id?: string): Promise<AgentPreset>
  * @throws when the preset is unknown or its composition is unusable.
  */
 async mount(agentCtx: Context, id?: string): Promise<AgentPreset>
+
+/**
+ * One agent's instance of a service its preset mounted.
+ *
+ * A preset publishes services behind `isolate` realms, which are invisible
+ * outside the group that declares them — including to the host. This is how a
+ * caller holding the agent reads one anyway: a request that is ABOUT a
+ * session but arrives from outside it, which is every browser RPC.
+ *
+ * Read addressing only. A host row that `inject`s a service cannot use this,
+ * because injection resolves before any session exists and has no agent to
+ * key by; such a service belongs on the host plane instead.
+ * @param agent - the agent whose composition to look inside.
+ * @param name - the service name as the preset's rows resolve it.
+ * @returns the agent's instance, or undefined when its preset mounts none.
+ */
+serviceFor<K extends string & keyof Context>(agent: { ctx: Context }, name: K): Context[K] | undefined
 ```
 
-Source: [`packages/preset/agent-presets/src/index.ts:37`](../../packages/preset/agent-presets/src/index.ts)
+Source: [`packages/preset/agent-presets/src/index.ts:39`](../../packages/preset/agent-presets/src/index.ts)
 
 ## `ctx.agents` — `AgentRegistry`
 
@@ -1390,7 +1407,7 @@ Source: [`packages/session-projection/session-projection-cache/src/index.ts:71`]
 
 ## `ctx.sessionProjections` — `SessionProjectionRegistry`
 
-`ctx.sessionProjections`: the projection unit table and its drive. The service subscribes to `session/event` once; every committed event passes every registered unit's `apply` (eager drive), and a changed state reference notifies the change feed with the schema-validated view. Cells build lazily — a unit registered after events flowed, or a session older than the registry, folds `init` over the in-memory log on first touch (event or read). Registration is an effect (disposer rides the calling fiber): an unloaded domain plugin's key disappears from snapshots and clients read it as capability absence. Duplicate keys throw. Domain plugins register under `ctx.inject(['sessionProjections'], …)` so headless assemblies without the registry stay unaffected.
+`ctx.sessionProjections`: the projection unit table and its drive. The service subscribes to `session/event` once; every committed event passes every registered unit's `apply` (eager drive), and a changed state reference notifies the change feed with the schema-validated view. Cells build lazily — a unit registered after events flowed, or a session older than the registry, folds `init` over the in-memory log on first touch (event or read). Registration is an effect (disposer rides the calling fiber): an unloaded domain plugin's key disappears from snapshots and clients read it as capability absence. Domain plugins register under `ctx.inject(['sessionProjections'], …)` so headless assemblies without the registry stay unaffected. Registrants sharing a key share one unit and are counted: the same tool package mounted in N agent presets registers N times, and the key survives until the last one unloads.
 
 ```ts cordis-catalog
 /**
@@ -1494,7 +1511,7 @@ restore(checkpoint: ProjectionCheckpoint, events: readonly SessionEvent[], baseS
 
 Types: [Session](../core-data-structures/session.md) · [SessionEvent](../core-data-structures/core.md)
 
-Source: [`packages/session-projection/session-projection/src/index.ts:156`](../../packages/session-projection/session-projection/src/index.ts)
+Source: [`packages/session-projection/session-projection/src/index.ts:171`](../../packages/session-projection/session-projection/src/index.ts)
 
 ## `ctx.sessionQuery` — `SessionQueryService` (abstract seam)
 
@@ -2273,7 +2290,7 @@ async assemble(context: AssembleContext = {}): Promise<PromptAssembly>
 
 Types: [AssembleContext](../core-data-structures/system-prompt.md) · [PromptContext](../core-data-structures/system-prompt.md) · [PromptSection](../core-data-structures/system-prompt.md) · [ToolProviderResult](../core-data-structures/system-prompt.md)
 
-Source: [`packages/core/system-prompt/src/index.ts:314`](../../packages/core/system-prompt/src/index.ts)
+Source: [`packages/core/system-prompt/src/index.ts:325`](../../packages/core/system-prompt/src/index.ts)
 
 ## `ctx.tasks` — `TaskService` (abstract seam)
 

docs/core-data-structures/persistence.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write docs/core-data-structures/persistence.md
-persistence.md: 65b000516894c6dfb4c661f0b9112197317197e6
-persistence.zh.md: 214b631063ae5368b95e2fa9603941eb7b3bbe64
+persistence.md: 1b8f124661399b610534ff787b11a4d4a743ad4d
+persistence.zh.md: 6099ceac46242a384098162cc6746de8e7d8dd7c

docs/module-graph.md

@@ -222,6 +222,7 @@ flowchart TD
   end
   subgraph group_preset["packages/preset"]
     pkg_agent_presets["agent-presets"]
+    pkg_persona["persona"]
   end
   subgraph group_pty["packages/pty"]
     pkg_pty["pty"]
@@ -303,7 +304,6 @@ flowchart TD
   pkg_client_web_react --> pkg_invariants
   pkg_code_runtime --> pkg_invariants
   pkg_jsonrpc_demo --> pkg_invariants
-  pkg_host_apiproxy --> pkg_invariants
   pkg_host_directory_picker --> pkg_invariants
   pkg_host_webserver --> pkg_invariants
   pkg_storage --> pkg_invariants
@@ -322,11 +322,6 @@ flowchart TD
   pkg_client_locale --> pkg_client_ui_primitives
   pkg_client_locale --> pkg_client_ui_slots
   pkg_client_locale --> pkg_invariants
-  pkg_client_test_runtime --> pkg_client_runtime
-  pkg_client_test_runtime --> pkg_client_ui_slots
-  pkg_client_test_runtime --> pkg_client_web_react
-  pkg_client_test_runtime --> pkg_host_apiproxy
-  pkg_client_test_runtime --> pkg_invariants
   pkg_client_ui_settings --> pkg_client_runtime
   pkg_client_ui_settings --> pkg_client_ui_primitives
   pkg_client_ui_settings --> pkg_client_ui_slots
@@ -419,6 +414,8 @@ flowchart TD
   pkg_credentials_local --> pkg_credentials
   pkg_credentials_local --> pkg_invariants
   pkg_credentials_local --> pkg_paths
+  pkg_host_apiproxy --> pkg_agent_presets
+  pkg_host_apiproxy --> pkg_invariants
   pkg_lsp --> pkg_brand
   pkg_lsp --> pkg_invariants
   pkg_lsp --> pkg_llm
@@ -463,6 +460,11 @@ flowchart TD
   pkg_app_boot --> pkg_invariants
   pkg_app_boot --> pkg_paths
   pkg_app_boot --> pkg_system_prompt
+  pkg_client_test_runtime --> pkg_client_runtime
+  pkg_client_test_runtime --> pkg_client_ui_slots
+  pkg_client_test_runtime --> pkg_client_web_react
+  pkg_client_test_runtime --> pkg_host_apiproxy
+  pkg_client_test_runtime --> pkg_invariants
   pkg_client_ui_layout --> pkg_client_runtime
   pkg_client_ui_layout --> pkg_client_ui_slots
   pkg_client_ui_layout --> pkg_client_ui_theme
@@ -492,6 +494,8 @@ flowchart TD
   pkg_lsp_local --> pkg_lsp
   pkg_lsp_local --> pkg_subprocess
   pkg_lsp_local --> pkg_timeout
+  pkg_persona --> pkg_invariants
+  pkg_persona --> pkg_system_prompt
   pkg_sandbox_local --> pkg_invariants
   pkg_sandbox_local --> pkg_llm
   pkg_sandbox_local --> pkg_sandbox
@@ -1122,7 +1126,6 @@ flowchart TD
 | [`client-web-react`](../packages/client/web-react) | `client` | [`invariants`](../packages/support/invariants) |
 | [`code-runtime`](../packages/code-runtime/code-runtime) | `code-runtime` | [`invariants`](../packages/support/invariants) |
 | [`jsonrpc-demo`](../packages/examples/jsonrpc-demo) | `examples` | [`invariants`](../packages/support/invariants) |
-| [`host-apiproxy`](../packages/host/apiproxy) | `host` | [`invariants`](../packages/support/invariants) |
 | [`host-directory-picker`](../packages/host/directory-picker) | `host` | [`invariants`](../packages/support/invariants) |
 | [`host-webserver`](../packages/host/webserver) | `host` | [`invariants`](../packages/support/invariants) |
 | [`storage`](../packages/storage/storage) | `storage` | [`invariants`](../packages/support/invariants) |
@@ -1133,7 +1136,6 @@ flowchart TD
 | [`client-connection`](../packages/client/connection) | `client` | [`host-webserver`](../packages/host/webserver), [`invariants`](../packages/support/invariants) |
 | [`client-hmr`](../packages/client/hmr) | `client` | [`client-modules`](../packages/client/modules), [`host-webserver`](../packages/host/webserver), [`invariants`](../packages/support/invariants) |
 | [`client-locale`](../packages/client/locale) | `client` | [`client-runtime`](../packages/client/runtime), [`client-ui-primitives`](../packages/client/ui-primitives), [`client-ui-slots`](../packages/client/ui-slots), [`invariants`](../packages/support/invariants) |
-| [`client-test-runtime`](../packages/client/test-runtime) | `client` | [`client-runtime`](../packages/client/runtime), [`client-ui-slots`](../packages/client/ui-slots), [`client-web-react`](../packages/client/web-react), [`host-apiproxy`](../packages/host/apiproxy), [`invariants`](../packages/support/invariants) |
 | [`client-ui-settings`](../packages/client/ui-settings) | `client` | [`client-runtime`](../packages/client/runtime), [`client-ui-primitives`](../packages/client/ui-primitives), [`client-ui-slots`](../packages/client/ui-slots), [`invariants`](../packages/support/invariants) |
 | [`client-ui-trajectory`](../packages/client/ui-trajectory) | `client` | [`client-runtime`](../packages/client/runtime), [`client-ui-primitives`](../packages/client/ui-primitives), [`invariants`](../packages/support/invariants) |
 | [`credentials`](../packages/credentials/credentials) | `credentials` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants) |
@@ -1160,6 +1162,7 @@ flowchart TD
 | [`client-ui-theme`](../packages/client/ui-theme) | `client` | [`client-locale`](../packages/client/locale), [`client-runtime`](../packages/client/runtime), [`client-ui-primitives`](../packages/client/ui-primitives), [`client-ui-slots`](../packages/client/ui-slots), [`invariants`](../packages/support/invariants) |
 | [`client-ui-workspace`](../packages/client/ui-workspace) | `client` | [`client-locale`](../packages/client/locale), [`client-runtime`](../packages/client/runtime), [`client-ui-primitives`](../packages/client/ui-primitives), [`client-ui-slots`](../packages/client/ui-slots), [`invariants`](../packages/support/invariants) |
 | [`credentials-local`](../packages/credentials/credentials-local) | `credentials` | [`atomic-write`](../packages/util/atomic-write), [`credentials`](../packages/credentials/credentials), [`invariants`](../packages/support/invariants), [`paths`](../packages/util/paths) |
+| [`host-apiproxy`](../packages/host/apiproxy) | `host` | [`agent-presets`](../packages/preset/agent-presets), [`invariants`](../packages/support/invariants) |
 | [`lsp`](../packages/lsp/lsp) | `lsp` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm) |
 | [`sandbox`](../packages/sandbox/sandbox) | `sandbox` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm) |
 | [`settings-local`](../packages/settings/settings-local) | `settings` | [`atomic-write`](../packages/util/atomic-write), [`invariants`](../packages/support/invariants), [`paths`](../packages/util/paths), [`settings`](../packages/settings/settings) |
@@ -1174,12 +1177,14 @@ flowchart TD
 | [`session-persistence`](../packages/session-persistence/session-persistence) | `session-persistence` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`session`](../packages/core/session) |
 | [`llm-replay`](../packages/support/llm-replay) | `support` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session) |
 | [`app-boot`](../packages/ui/app-boot) | `ui` | [`invariants`](../packages/support/invariants), [`paths`](../packages/util/paths), [`system-prompt`](../packages/core/system-prompt) |
+| [`client-test-runtime`](../packages/client/test-runtime) | `client` | [`client-runtime`](../packages/client/runtime), [`client-ui-slots`](../packages/client/ui-slots), [`client-web-react`](../packages/client/web-react), [`host-apiproxy`](../packages/host/apiproxy), [`invariants`](../packages/support/invariants) |
 | [`client-ui-layout`](../packages/client/ui-layout) | `client` | [`client-runtime`](../packages/client/runtime), [`client-ui-slots`](../packages/client/ui-slots), [`client-ui-theme`](../packages/client/ui-theme), [`invariants`](../packages/support/invariants) |
 | [`client-ui-skill`](../packages/client/ui-skill) | `client` | [`client-connection`](../packages/client/connection), [`client-runtime`](../packages/client/runtime), [`client-ui-slash`](../packages/client/ui-slash), [`client-ui-slots`](../packages/client/ui-slots), [`invariants`](../packages/support/invariants) |
 | [`code-runtime-worker`](../packages/code-runtime/code-runtime-worker) | `code-runtime` | [`code-runtime`](../packages/code-runtime/code-runtime), [`invariants`](../packages/support/invariants), [`session`](../packages/core/session), [`timeout`](../packages/util/timeout) |
 | [`host-directory-picker-browse`](../packages/host/directory-picker-browse) | `host` | [`client-locale`](../packages/client/locale), [`client-runtime`](../packages/client/runtime), [`client-ui-primitives`](../packages/client/ui-primitives), [`client-ui-slots`](../packages/client/ui-slots), [`client-ui-workspace`](../packages/client/ui-workspace), [`invariants`](../packages/support/invariants) |
 | [`host-directory-picker-native`](../packages/host/directory-picker-native) | `host` | [`client-runtime`](../packages/client/runtime), [`client-ui-slots`](../packages/client/ui-slots), [`client-ui-workspace`](../packages/client/ui-workspace), [`invariants`](../packages/support/invariants) |
 | [`lsp-local`](../packages/lsp/lsp-local) | `lsp` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`lsp`](../packages/lsp/lsp), [`subprocess`](../packages/subprocess/subprocess), [`timeout`](../packages/util/timeout) |
+| [`persona`](../packages/preset/persona) | `preset` | [`invariants`](../packages/support/invariants), [`system-prompt`](../packages/core/system-prompt) |
 | [`sandbox-local`](../packages/sandbox/sandbox-local) | `sandbox` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`sandbox`](../packages/sandbox/sandbox) |
 | [`session-projection`](../packages/session-projection/session-projection) | `session-projection` | [`invariants`](../packages/support/invariants), [`session`](../packages/core/session) |
 | [`llm-retry`](../packages/llm/llm-retry) | `llm` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`timeout`](../packages/util/timeout) |

packages/bundle/web-app/cordis.patch.yml

@@ -300,7 +300,8 @@
 - id: tool-web
   disabled: true
 
-# The preset roster. `.system` ships with the deployment and is read-only;
+# The preset roster. `config/agent-presets/` ships with the deployment and is
+# read-only (its entries carry `system` trust);
 # `$DSH_HOME/.agent-presets` is where a person — or an agent — authors their own, and
 # carries the same trust as shell access because a preset IS a composition.
 # `roots` is an assembly fact, not user config: the shipped preset directory

packages/bundle/web-app/package.json

@@ -32,6 +32,7 @@
     }
   },
   "dependencies": {
+    "@deepseek-ai/dsh-agent-presets": "workspace:^",
     "@deepseek-ai/dsh-client-connection": "workspace:^",
     "@deepseek-ai/dsh-client-hmr": "workspace:^",
     "@deepseek-ai/dsh-client-locale": "workspace:^",

packages/cordis/tool-cordis/src/api-catalog.ts

@@ -96,6 +96,10 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
         signature: 'async mount(agentCtx: Context, id?: string): Promise<AgentPreset>',
         jsDoc: '/**\n * Compose one agent from a preset, installing it under that agent alone.\n *\n * Call from the agent factory\'s `setup(agentCtx)`; a rejection there rolls\n * the agent creation back, so a broken preset never yields a half-composed\n * session.\n * @param agentCtx - the agent\'s scope context.\n * @param id - the preset id, or `undefined` for {@link defaultId}.\n * @returns the preset that was mounted, for the caller to record.\n * @throws when the preset is unknown or its composition is unusable.\n */',
       },
+      {
+        signature: 'serviceFor<K extends string & keyof Context>(agent: { ctx: Context }, name: K): Context[K] | undefined',
+        jsDoc: '/**\n * One agent\'s instance of a service its preset mounted.\n *\n * A preset publishes services behind `isolate` realms, which are invisible\n * outside the group that declares them — including to the host. This is how a\n * caller holding the agent reads one anyway: a request that is ABOUT a\n * session but arrives from outside it, which is every browser RPC.\n *\n * Read addressing only. A host row that `inject`s a service cannot use this,\n * because injection resolves before any session exists and has no agent to\n * key by; such a service belongs on the host plane instead.\n * @param agent - the agent whose composition to look inside.\n * @param name - the service name as the preset\'s rows resolve it.\n * @returns the agent\'s instance, or undefined when its preset mounts none.\n */',
+      },
     ],
   },
   {

packages/core/system-prompt/src/index.ts

@@ -110,6 +110,17 @@ export interface PromptAssembly {
   variables: Record<string, string | undefined>
 }
 
+/**
+ * The deployment persona's section name and order. Exported because a
+ * composition can replace this slot — an agent preset shadows the
+ * deployment's persona with its own — and both sides naming the same section
+ * is what makes the replacement work rather than duplicate.
+ */
+export const PERSONA_SECTION = 'deployment:persona'
+
+/** Prompt order of the persona slot; the first section a model reads. */
+export const PERSONA_ORDER = 0
+
 /** Valid variable names: how they are written between the braces. */
 const VARIABLE_NAME = /^[a-z][a-z0-9_]*$/
 
@@ -337,8 +348,8 @@ export class SystemPrompt extends Service {
       })
     }
     this.section({
-      name: 'deployment:persona',
-      order: 0,
+      name: PERSONA_SECTION,
+      order: PERSONA_ORDER,
       // The fallback narrows the optional input type; the schema already defaults it.
       text: config.persona ?? '',
     })

packages/host/apiproxy/src/api-proxy.ts

@@ -642,7 +642,6 @@ class SubagentSessionOwnership extends Error {
   }
 }
 
-/** Requested identity already belongs to a session with another project cwd. */
 /**
  * The requested preset differs from the one this session already runs.
  *
@@ -658,12 +657,16 @@ class AgentPresetConflict extends Error {
     readonly existingPreset: string | undefined,
   ) {
     super(
-      `session "${sessionId}" already runs agent preset ${JSON.stringify(existingPreset)}; `
+      existingPreset === undefined
+        ? `session "${sessionId}" records no agent preset, so it cannot be adopted under one; `
+        + 'a deployment composing no roster records none on any session — '
+        : `session "${sessionId}" already runs agent preset ${JSON.stringify(existingPreset)}; `
       + `requested ${JSON.stringify(requestedPreset)}. A session's preset is fixed at creation.`,
     )
   }
 }
 
+/** Requested identity already belongs to a session with another project cwd. */
 class SessionCwdConflict extends Error {
   constructor(
     readonly sessionId: SessionId,

packages/host/apiproxy/tests/api-proxy-agent-preset.spec.ts

@@ -153,6 +153,28 @@ describe('session.create with an agent preset', () => {
 
     expect(ctx.sessions.get(SessionId('s6'))?.header.agentPreset).toBeUndefined()
   })
+
+  it('says why a preset-less session cannot be adopted under one', async () => {
+    // Two callers reach this: a deployment that composes no roster, and a
+    // session created before one existed. Both record no preset, so naming
+    // any is a conflict rather than an adoption — the history was produced
+    // under a composition this roster cannot name. The message has to say
+    // that, because "already runs agent preset undefined" reads as a bug.
+    const { api } = await harness()
+    await api.sessions.create(request({ sessionId: SessionId('s7') }))
+
+    const response = await api.sessions.create(request({ sessionId: SessionId('s7'), agentPreset: 'standard' }))
+
+    expect(response.result.ok).toBe(false)
+    if (response.result.ok) throw new Error('unreachable')
+    expect(response.result.error.code).toBe('agent-preset-conflict')
+    expect(response.result.error.message).toContain('records no agent preset')
+    expect(response.result.error.details).toEqual({
+      sessionId: 's7',
+      requestedPreset: 'standard',
+      existingPreset: undefined,
+    })
+  })
 })
 
 /**

packages/preset/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/preset/README.md
-README.md: fcce3013174b5c3b7e545eb48e73cc1d8f4126dc
-README.zh.md: 281885daae9aab8dc989c232e751f9a255075b96
+README.md: d2ed10014af506809b5fd117e08b09b45a31a16c
+README.zh.md: db7bf18e6ba841cc705eafae7c09d4c5d26581b1

packages/preset/agent-presets/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/preset/agent-presets/README.md
-README.md: 8c95719bead97845519b7a334603005df201a34d
-README.zh.md: c5e2fd3c7896437ddb4a2acdf101cd2e0e0eedaf
+README.md: 1592fba1163448aaedbd482c56962fa07ebc897e
+README.zh.md: ef4512ab93783674890bc9a848e590792a820e8c

packages/preset/agent-presets/src/mount.ts

@@ -61,6 +61,11 @@ class PresetTree extends Include {
    * shipped composition to `[]` the first time a session ends. Persisting a
    * preset is also meaningless: nothing here is user state, and the same file
    * backs every session that names it.
+   *
+   * Dropping the write drops the `loader/config-update` the inherited method
+   * emits with it. Nothing observes one for a preset subtree today, and a
+   * future "edit your preset while it runs" flow needs a deliberate
+   * persistence path rather than this method's return.
    */
   override write(): void {
   }

packages/preset/persona/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/preset/persona/README.md
-README.md: 3a9f9f2e2debf9d4274949e14913137ef752baae
-README.zh.md: 2c3bac3bb4a1fbeeb9c30defb225c2b64cb3e577
+README.md: 789776b32d907f7d217accccbca5508f88de0ed1
+README.zh.md: 4e28d75bbd4fd22b77a0fa3b18c5f19df08588d8

packages/preset/persona/package.json

@@ -21,9 +21,7 @@
   "files": [
     "lib/index.js",
     "lib/invariant.js",
-    "lib/types/**/*.d.ts",
-    "lib/types/**/*.d.ts.map",
-    "src"
+    "lib/types/**/*.d.ts"
   ],
   "license": "BSD-3-Clause",
   "peerDependencies": {

packages/preset/persona/src/index.ts

@@ -17,11 +17,12 @@ import type { Context } from 'cordis'
 import z from 'schemastery'
 import type {} from '@deepseek-ai/dsh-system-prompt'
 
-/** The section name this plugin registers; the prompt registry's persona slot. */
-export const PERSONA_SECTION = 'deployment:persona'
+// Imported rather than restated: the registry declares the slot this row
+// replaces, and two hardcoded copies would drift into a preset whose persona
+// silently lands beside the deployment's instead of shadowing it.
+import { PERSONA_ORDER, PERSONA_SECTION } from '@deepseek-ai/dsh-system-prompt'
 
-/** Prompt order of the persona slot, matching the registry's own default. */
-export const PERSONA_ORDER = 0
+export { PERSONA_ORDER, PERSONA_SECTION }
 
 /** Cordis plugin name. */
 export const name = 'persona'

pnpm-lock.yaml

@@ -1089,6 +1089,9 @@ importers:
 
   packages/bundle/web-app:
     dependencies:
+      '@deepseek-ai/dsh-agent-presets':
+        specifier: workspace:^
+        version: link:../../preset/agent-presets
       '@deepseek-ai/dsh-client-connection':
         specifier: workspace:^
         version: link:../../client/connection