diff --git a/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.i18n.yaml b/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.i18n.yaml
new file mode 100644
index 0000000000..7bcfa9f599
--- /dev/null
+++ b/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.i18n.yaml
@@ -0,0 +1,6 @@
+# Bilingual-pair consistency record (docs/i18n/README.md): the git blob hash of each
+# 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 .agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.md
+2026-07-31-telemetry-anonymous-user-id.md: 3c8e3324cb418eac48cb5ae780c55bbcbaf3caa1
+2026-07-31-telemetry-anonymous-user-id.zh.md: 9ff6cf35a90d4087b4ab75987dc9244210e3d46a
diff --git a/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.md b/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.md
new file mode 100644
index 0000000000..3c8e3324cb
--- /dev/null
+++ b/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.md
@@ -0,0 +1,44 @@
+# Agent Note: Telemetry anonymous user id ($DSH_HOME/.userid) and the OTel Resource user.id
+
+Status: implemented
+
+English | [中文](2026-07-31-telemetry-anonymous-user-id.zh.md)
+
+## Problem
+
+Session telemetry is mounted by default ([default-mount Note](2026-07-31-web-telemetry-default-mount.md)), but the OTel Resource carried only `service.name`/`service.version` — no user-level identity at all, so the collector could neither aggregate per user nor count active users. The only prior ruling on point was an unimplemented one to derive a user id by hashing the hostname/local IP; the dsh-sdk toolchain keeps its own anonymous id (`$DSH_HOME/telemetry.json`), but that is the launcher feed's private fact, unrelated to the OTel feed. The OTel feed needed an anonymous user identity with clean semantics.
+
+## Decision
+
+The `session-telemetry-otel` package's own module `src/user-id.ts` owns the OTel feed's user identity: `getOrCreateAnonymousUserId()` returns the bare UUID line in `$DSH_HOME/.userid` (resolved by `resolveDshHome`, `$DSH_HOME` > `~/.dsh`), minting and persisting a random UUID v4 on first use; the backend constructor carries it as the Resource's `user.id` (the OTel semconv user attribute), once per export batch. This identity belongs to the OTel feed alone; the dsh-sdk launcher telemetry keeps its own anonymous-id store (`telemetry.json`), and the two are not shared (the first cut unified both feeds through a shared util package; the user reconsidered and pulled it back — no shared package before a second real consumer exists, revisit when a feed-correlation need appears).
+
+| Ruling | Value | Rationale |
+|---|---|---|
+| Id source | Random UUID v4, never derived from the hostname, network address, or git remote | A derived id is reversible, making "anonymous" a fiction |
+| Storage form | `.userid`, a bare UUID line plus newline, no JSON wrapper | Identity is a standalone fact, not something filed under one telemetry feed's file name/format |
+| IO form | Synchronous IO + a process-lifetime memo keyed by resolved file path | `TelemetryOtel`'s constructor is synchronous (async would reshape plugin loading); one disk touch per process, and mid-run file deletion never affects the running process |
+| Concurrent first launch | Settled by an exclusive-create (`wx`) write; the loser rereads the winner's id | Covers common concurrency (a reread landing in the winner's microsecond create-to-write window can still yield one id per process for that run, converging on the persisted value next launch — a telemetry-grade consequence, accepted) |
+| Loss semantics | File deleted → next launch mints a fresh id; loss is accepted | An anonymous identity has no recovery value; recoverability demands derivation material, which conflicts with anonymity |
+| Write failure | Best-effort: return the in-memory id | Telemetry is never blocked by a read-only home |
+| Report position | Resource attribute, not per-record attributes | Once per batch suffices for Resource-dimension aggregation; per-record injection would touch the seam contract and grow the wire |
+| semconv dependency | `@opentelemetry/semantic-conventions` is not imported | One string constant does not justify a dependency |
+| Home | A module inside `session-telemetry-otel`, not a shared util package | Repo rule: split a package only for a second real consumer; the sdk launcher feed keeps its own store, and no real correlation need exists |
+| Separate switch | None | Identity follows the telemetry master switch (`DSH_TELEMETRY_DISABLED`); telemetry off means nothing reports |
+
+## Alternatives considered
+
+| Rejected | One-line reason |
+|---|---|
+| Hostname/IP-hash-derived id (the prior ruling) | Reversible means not anonymous; the random UUID is semantically clean — the user ruled to supersede |
+| user.id on every record's attributes (Claude Code's shape) | Touches the session-telemetry seam contract or injects per record, growing the wire; once per batch on the Resource already aggregates |
+| A shared util package unifying both feeds (the first cut) | The only real consumer is the OTel backend; switching the sdk launcher onto it was unification for its own sake — the user reconsidered and pulled it back, to be re-extracted when a correlation need appears |
+| Reusing telemetry.json instead of a new file | The file name/JSON format files the identity under the launcher feed's naming; the OTel feed's identity is a standalone fact |
+| AppCLIEntry reading the id and injecting via config patch | Every surface entry needs wiring; a runtime fact inside deployment config conflates the two |
+| Housing it in `@deepseek-ai/dsh-paths` | paths is pure path computation with zero IO; a persisting identity capability would pollute the package boundary |
+
+## Consequences
+
+- One `$DSH_HOME` is one stable user in the OTel feed; separate homes are separate users by construction, with no cross-home linking mechanism.
+- The OTel feed and the launcher feed each hold their own id (`.userid` vs `telemetry.json`) and cannot be correlated — the direct cost of not extracting a shared package, to be unified when a real correlation need appears.
+- Deleting `.userid` resets the identity (effective next launch); on an unwritable home each process holds its own in-memory id until the home becomes writable.
+- The [default-mount Note](2026-07-31-web-telemetry-default-mount.md)'s identity follow-up is closed for the anonymous-user-id part by this decision; hostname/surface dimensions, the redaction rule, and the usage-metrics track remain open.
diff --git a/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.zh.md b/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.zh.md
new file mode 100644
index 0000000000..9ff6cf35a9
--- /dev/null
+++ b/.agents/notes/implemented/feature/2026-07-31-telemetry-anonymous-user-id.zh.md
@@ -0,0 +1,44 @@
+# Agent Note: telemetry 匿名用户 id（$DSH_HOME/.userid）与 OTel Resource user.id
+
+Status: implemented
+
+[English](2026-07-31-telemetry-anonymous-user-id.md) | 中文
+
+## Problem
+
+session telemetry 已默认挂载（[默认挂载 Note](2026-07-31-web-telemetry-default-mount.md)），但 OTel Resource 只有 `service.name`/`service.version`，没有任何用户级标识——接收端无法按用户聚合、无法数活跃用户。此前唯一相关口径是一条未实现的「hostname/本机 IP 哈希派生 user.id」裁定；dsh-sdk 工具链另有自用的匿名 id（`$DSH_HOME/telemetry.json`），但那是 launcher 回流的私有事实，与 OTel 回流无关。需要给 OTel 回流一个语义干净的匿名用户身份。
+
+## Decision
+
+`session-telemetry-otel` 包内模块 `src/user-id.ts` 是 OTel 回流用户身份的属主：`getOrCreateAnonymousUserId()` 返回 `$DSH_HOME/.userid`（`resolveDshHome` 解析，`$DSH_HOME` > `~/.dsh`）中的裸 UUID 行，首用生成随机 UUID v4 并落盘；backend 构造时把它作为 Resource 的 `user.id`（OTel semconv 标准用户属性）随每批导出携带一次。该身份只属于 OTel 回流；dsh-sdk launcher telemetry 保留自己的匿名 id 存储（`telemetry.json`），两者不共享（初版曾做公用 util 包统一两条回流，用户复议后收回：在有第二个真实消费者之前不抽公共包，回流关联需求出现时再议）。
+
+| 裁定 | 取值 | 理由 |
+|---|---|---|
+| id 来源 | 随机 UUID v4，绝不从 hostname/网络地址/git remote 派生 | 派生 id 可反查，「匿名」名不副实 |
+| 存储形态 | `.userid` 裸 UUID 行 + 换行，无 JSON 包装 | 身份是独立事实，不挂在某条 telemetry 链路的文件命名/格式下 |
+| 读写形态 | 同步 IO + 进程内按解析后文件路径 memo | `TelemetryOtel` 构造函数是同步的（async 迫使插件装载改形）；一进程一次盘 IO，运行中删文件不影响本进程 |
+| 并发首启 | `wx` 独占写裁决，落败方重读胜者 id | 覆盖常见并发（重读撞进胜者建档-写入微秒窗仍可能各持一 id 一次运行，下次启动收敛到落盘值——telemetry 级后果，接受） |
+| 丢失语义 | 文件被删 → 下次启动换新 id，接受丢失 | 匿名身份无恢复价值；可恢复性要求派生材料，与匿名冲突 |
+| 写失败 | best-effort 返回内存 id | telemetry 永不因 home 只读被阻塞 |
+| 上报位置 | Resource 属性，非逐条 attributes | 每批一次即够接收端按 Resource 维度聚合；逐条注入要动 seam 契约且涨 wire 体积 |
+| semconv 依赖 | 不引 `@opentelemetry/semantic-conventions` 包 | 一个字符串常量不值一个依赖 |
+| 落点 | `session-telemetry-otel` 包内模块，非公共 util 包 | 仓规「有第二个真实消费者才拆包」；sdk launcher 回流保留自有存储，无现实关联需求 |
+| 单独开关 | 无 | 身份跟随 telemetry 整体开关（`DSH_TELEMETRY_DISABLED`）；关 telemetry 即整体不报 |
+
+## Alternatives considered
+
+| 被拒 | 一句话理由 |
+|---|---|
+| hostname/IP 哈希派生 id（此前口径） | 可反查即非匿名；随机 UUID 语义干净，用户裁决取代 |
+| user.id 放每条 record 的 attributes（Claude Code 形态） | 要动 session-telemetry seam 契约或逐条注入，wire 体积涨；Resource 每批一次已满足聚合 |
+| 公用 util 包统一两条回流（初版实现） | 唯一现实消费者是 OTel backend；sdk launcher 换用它只是为统一而统一——用户复议收回，回流关联需求出现时再抽包 |
+| 复用 telemetry.json 不新建文件 | 文件名/JSON 格式把身份挂在 launcher 链路命名下；OTel 回流身份是独立事实 |
+| AppCLIEntry 读好 id 经 config patch 注入 | 每个 surface 入口都要接线；config 里传运行时事实与部署配置混淆 |
+| 挂进 `@deepseek-ai/dsh-paths` | paths 是纯路径计算零 IO；带持久化的身份能力会污染包边界 |
+
+## Consequences
+
+- 一个 `$DSH_HOME` 在 OTel 回流中是一个稳定用户；不同 home 在构造上就是不同用户，无跨 home 关联机制。
+- OTel 回流与 launcher 回流各有各的 id（`.userid` 与 `telemetry.json`），无法互相关联——这是「不抽公共包」的直接代价，等真实关联需求出现再统一。
+- 删除 `.userid` 即重置身份（下次启动生效）；home 不可写时每进程各自持有一个内存 id 直至恢复可写。
+- [默认挂载 Note](2026-07-31-web-telemetry-default-mount.md) 的身份 follow-up 中「匿名用户 id」项由本决定关闭；hostname/surface 维度与脱敏规则、usage-metrics track 仍是待办。
diff --git a/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.i18n.yaml b/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.i18n.yaml
index 97793a906a..dd15a55a21 100644
--- a/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.i18n.yaml
+++ b/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.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 .agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.md
-2026-07-31-web-telemetry-default-mount.md: 6c1fdaa8719ee01726b51db9a469ff659cbac476
-2026-07-31-web-telemetry-default-mount.zh.md: b447832527ba9731097cd0776060db11ee4dfc30
+2026-07-31-web-telemetry-default-mount.md: e9ec7d0cda37db44e753c9aee572763b7e24ada6
+2026-07-31-web-telemetry-default-mount.zh.md: 68b411d0668772ce81d7f323c2d286714a223ca4
diff --git a/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.md b/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.md
index 6c1fdaa871..e9ec7d0cda 100644
--- a/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.md
+++ b/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.md
@@ -35,5 +35,5 @@ The keyless integration test `apps/cli/tests/telemetry-web.e2e.ts` pins the depl
 ## Consequences
 
 - A developer running `dsh web` without a local collector POSTs to the production endpoint every 10s (silent failure when unreachable; no OTel diag logger is registered); local development sets `DSH_TELEMETRY_DISABLED=1` or points `DSH_TELEMETRY_OTLP_URL` locally.
-- **No redaction rule is mounted yet**: exports are the raw captured copy (full user/assistant message text, tool arguments and results, the system prompt, the local `session.cwd` path). Crossing a trust boundary requires `telemetry/record` rules first — the redaction rule, identity Resource attributes (hostname / anonymous user id / surface), and the usage-metrics track are the explicit follow-ups of this decision.
+- **No redaction rule is mounted yet**: exports are the raw captured copy (full user/assistant message text, tool arguments and results, the system prompt, the local `session.cwd` path). Crossing a trust boundary requires `telemetry/record` rules first — the redaction rule, the remaining identity Resource attributes (hostname / surface; the anonymous user id shipped via the [anonymous-user-id Note](2026-07-31-telemetry-anonymous-user-id.md)), and the usage-metrics track are the explicit follow-ups of this decision.
 - Test rigs reusing this tree (e.g. `apps/web/tests/scaffold.ts`) must explicitly disable the row, or fixture sessions stream to whatever collector the environment happens to name.
diff --git a/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.zh.md b/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.zh.md
index b447832527..68b411d066 100644
--- a/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.zh.md
+++ b/.agents/notes/implemented/feature/2026-07-31-web-telemetry-default-mount.zh.md
@@ -35,5 +35,5 @@ Status: implemented
 ## Consequences
 
 - 无本地 collector 的开发者跑 `dsh web` 会对生产 endpoint 每 10s 发一次 POST（联不通则静默失败，OTel diag logger 未注册）；本地开发设 `DSH_TELEMETRY_DISABLED=1` 或 `DSH_TELEMETRY_OTLP_URL` 指本地。
-- **当前零脱敏规则挂载**：导出即原始捕获副本（用户/助手消息全文、工具参数与结果、system prompt、`session.cwd` 本地路径）。跨信任边界前必须挂 `telemetry/record` 规则——脱敏规则、身份 Resource 维度（hostname/匿名 user id/surface）、使用数据 metrics 轨三件是本决策明确的后续工作。
+- **当前零脱敏规则挂载**：导出即原始捕获副本（用户/助手消息全文、工具参数与结果、system prompt、`session.cwd` 本地路径）。跨信任边界前必须挂 `telemetry/record` 规则——脱敏规则、其余身份 Resource 维度（hostname/surface；匿名 user id 已由[匿名用户 id Note](2026-07-31-telemetry-anonymous-user-id.md)落地）、使用数据 metrics 轨是本决策明确的后续工作。
 - 复用这棵树的测试载具（如 `apps/web/tests/scaffold.ts`）须显式关停该行，否则 fixture 会话会流向 env 里碰巧存在的 collector。
diff --git a/apps/cli/config/base.cordis.yml b/apps/cli/config/base.cordis.yml
index 5e0940d241..041e7939bc 100644
--- a/apps/cli/config/base.cordis.yml
+++ b/apps/cli/config/base.cordis.yml
@@ -105,7 +105,9 @@
 # DSH_TELEMETRY_OTLP_URL overrides the production endpoint, and a non-empty
 # DSH_TELEMETRY_DISABLED — any value, including '0'/'false' — opts the
 # process out (the launchers patch the row disabled; config cannot disable
-# a row). The exporter/processor values bound the shutdown drain to ~1s
+# a row). Exports carry the harness home's anonymous user id ($DSH_HOME/.userid,
+# random UUID; delete the file to reset the identity) as the Resource's
+# user.id. The exporter/processor values bound the shutdown drain to ~1s
 # against an unreachable collector: exporter.timeoutMillis is both the
 # per-attempt socket timeout and the retry deadline (1s effectively
 # disables the SDK's 5-try backoff), maxExportBatchSize == maxQueueSize
diff --git a/docs/config-catalog.md b/docs/config-catalog.md
index 4b9b42df34..ce0d6d393e 100644
--- a/docs/config-catalog.md
+++ b/docs/config-catalog.md
@@ -1229,7 +1229,7 @@ export interface Config {
 
 Depends on: `BatchLogRecordProcessorOptions` (`@opentelemetry/sdk-logs`) · `OTLPExporterNodeConfigBase` (`@opentelemetry/otlp-exporter-base`)
 
-Source: [`packages/telemetry/session-telemetry-otel/src/index.ts:40`](../packages/telemetry/session-telemetry-otel/src/index.ts)
+Source: [`packages/telemetry/session-telemetry-otel/src/index.ts:41`](../packages/telemetry/session-telemetry-otel/src/index.ts)
 
 ## `@deepseek-ai/dsh-session-title`
 
diff --git a/docs/module-graph.md b/docs/module-graph.md
index 1a75d881e7..004ca5aa03 100644
--- a/docs/module-graph.md
+++ b/docs/module-graph.md
@@ -682,8 +682,10 @@ flowchart TD
   pkg_tasks_local --> pkg_invariants
   pkg_tasks_local --> pkg_tasks
   pkg_tasks_local --> pkg_timeout
+  pkg_session_telemetry_otel --> pkg_brand
   pkg_session_telemetry_otel --> pkg_invariants
   pkg_session_telemetry_otel --> pkg_llm
+  pkg_session_telemetry_otel --> pkg_paths
   pkg_session_telemetry_otel --> pkg_session
   pkg_session_telemetry_otel --> pkg_session_telemetry
   pkg_agent_loop --> pkg_agent
@@ -1157,7 +1159,7 @@ flowchart TD
 | [`client-ui-model`](../packages/client/ui-model) | `client` | [`client-connection`](../packages/client/connection), [`client-locale`](../packages/client/locale), [`client-runtime`](../packages/client/runtime), [`client-ui-command`](../packages/client/ui-command), [`client-ui-conversation`](../packages/client/ui-conversation), [`client-ui-primitives`](../packages/client/ui-primitives), [`client-ui-slash`](../packages/client/ui-slash), [`client-ui-slots`](../packages/client/ui-slots), [`invariants`](../packages/support/invariants) |
 | [`pty-local`](../packages/pty/pty-local) | `pty` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`pty`](../packages/pty/pty), [`sandbox`](../packages/sandbox/sandbox), [`sandbox-policy`](../packages/sandbox/sandbox-policy), [`session`](../packages/core/session), [`subprocess`](../packages/subprocess/subprocess) |
 | [`tasks-local`](../packages/tasks/tasks-local) | `tasks` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`tasks`](../packages/tasks/tasks), [`timeout`](../packages/util/timeout) |
-| [`session-telemetry-otel`](../packages/telemetry/session-telemetry-otel) | `telemetry` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-telemetry`](../packages/telemetry/session-telemetry) |
+| [`session-telemetry-otel`](../packages/telemetry/session-telemetry-otel) | `telemetry` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`paths`](../packages/util/paths), [`session`](../packages/core/session), [`session-telemetry`](../packages/telemetry/session-telemetry) |
 | [`agent-loop`](../packages/core/agent-loop) | `core` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`scope`](../packages/core/scope), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
 | [`tool-goal`](../packages/goal/tool-goal) | `goal` | [`agent`](../packages/core/agent), [`goal`](../packages/goal/goal), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
 | [`tool-bash`](../packages/bash/tool-bash) | `bash` | [`agent`](../packages/core/agent), [`bash`](../packages/bash/bash), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`paths`](../packages/util/paths), [`sandbox`](../packages/sandbox/sandbox), [`sandbox-policy`](../packages/sandbox/sandbox-policy), [`session-persistence`](../packages/session-persistence/session-persistence), [`system-prompt`](../packages/core/system-prompt), [`tasks`](../packages/tasks/tasks), [`tools`](../packages/core/tools), [`user-approval`](../packages/ui/user-approval) |
diff --git a/packages/telemetry/session-telemetry-otel/README.i18n.yaml b/packages/telemetry/session-telemetry-otel/README.i18n.yaml
index b1a2052a3f..db61f28a67 100644
--- a/packages/telemetry/session-telemetry-otel/README.i18n.yaml
+++ b/packages/telemetry/session-telemetry-otel/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/telemetry/session-telemetry-otel/README.md
-README.md: 9b208e291e77bee50d9d4fd14808268dca75f2db
-README.zh.md: 76de1bf1ad58a0239907f3b63c672177874c7966
+README.md: ad4a97868c28dc3873c839490aa506271459e249
+README.zh.md: f1ad73ddf66aacc30a9024a9290df2c44686efe9
diff --git a/packages/telemetry/session-telemetry-otel/README.md b/packages/telemetry/session-telemetry-otel/README.md
index 9b208e291e..ad4a97868c 100644
--- a/packages/telemetry/session-telemetry-otel/README.md
+++ b/packages/telemetry/session-telemetry-otel/README.md
@@ -2,7 +2,7 @@
 
 English | [中文](README.zh.md)
 
-The OpenTelemetry backend for [the telemetry seam](../session-telemetry/) — the only entry a deployment loads. It composes the OTel JS SDK as-is (`LoggerProvider` → `BatchLogRecordProcessor` → OTLP/HTTP log exporter) and maps each record the seam hands over onto `logger.emit()`, under two instrumentation scopes: ledger records on `@deepseek-ai/dsh-session-telemetry-otel`, operational records on `@deepseek-ai/dsh-session-telemetry-otel/ops`. Resource identity (`service.name`/`service.version`) comes from `dsh-llm`'s `APP_IDENTITY`, the same source the attribution headers use.
+The OpenTelemetry backend for [the telemetry seam](../session-telemetry/) — the only entry a deployment loads. It composes the OTel JS SDK as-is (`LoggerProvider` → `BatchLogRecordProcessor` → OTLP/HTTP log exporter) and maps each record the seam hands over onto `logger.emit()`, under two instrumentation scopes: ledger records on `@deepseek-ai/dsh-session-telemetry-otel`, operational records on `@deepseek-ai/dsh-session-telemetry-otel/ops`. Resource identity (`service.name`/`service.version`) comes from `dsh-llm`'s `APP_IDENTITY`, the same source the attribution headers use, plus `user.id` — the harness home's anonymous user id this package owns (`src/user-id.ts`: `$DSH_HOME/.userid`, a random UUID minted on first use; deleting the file resets the identity), carried once per export batch on the Resource rather than per record.
 
 ## Config
 
diff --git a/packages/telemetry/session-telemetry-otel/README.zh.md b/packages/telemetry/session-telemetry-otel/README.zh.md
index 76de1bf1ad..f1ad73ddf6 100644
--- a/packages/telemetry/session-telemetry-otel/README.zh.md
+++ b/packages/telemetry/session-telemetry-otel/README.zh.md
@@ -2,7 +2,7 @@
 
 [English](README.md) | 中文
 
-[遥测（telemetry）seam](../session-telemetry/) 的 OpenTelemetry 后端，也是部署方唯一要加载的条目。它原样组合 OTel JS SDK（`LoggerProvider` → `BatchLogRecordProcessor` → OTLP/HTTP 日志导出器），把 seam 交接过来的每条记录映射到 `logger.emit()`，并使用两个插桩作用域（instrumentation scope）：ledger 记录挂在 `@deepseek-ai/dsh-session-telemetry-otel` 下，运维记录挂在 `@deepseek-ai/dsh-session-telemetry-otel/ops` 下。资源身份（`service.name`/`service.version`）来自 `dsh-llm` 的 `APP_IDENTITY`，与归因标头同源。
+[遥测（telemetry）seam](../session-telemetry/) 的 OpenTelemetry 后端，也是部署方唯一要加载的条目。它原样组合 OTel JS SDK（`LoggerProvider` → `BatchLogRecordProcessor` → OTLP/HTTP 日志导出器），把 seam 交接过来的每条记录映射到 `logger.emit()`，并使用两个插桩作用域（instrumentation scope）：ledger 记录挂在 `@deepseek-ai/dsh-session-telemetry-otel` 下，运维记录挂在 `@deepseek-ai/dsh-session-telemetry-otel/ops` 下。资源身份（`service.name`/`service.version`）来自 `dsh-llm` 的 `APP_IDENTITY`，与归因标头同源；另有 `user.id`——本包自有的 harness home 匿名用户 id（`src/user-id.ts`：`$DSH_HOME/.userid`，首用生成随机 UUID；删除该文件即重置身份），随 Resource 每批导出携带一次而非逐条携带。
 
 ## 配置
 
diff --git a/packages/telemetry/session-telemetry-otel/package.json b/packages/telemetry/session-telemetry-otel/package.json
index 7be8c04ce4..49e9ef6cad 100644
--- a/packages/telemetry/session-telemetry-otel/package.json
+++ b/packages/telemetry/session-telemetry-otel/package.json
@@ -36,16 +36,20 @@
     "schemastery": "^3.18.0"
   },
   "peerDependencies": {
+    "@deepseek-ai/dsh-brand": "^0.0.1",
     "@deepseek-ai/dsh-invariants": "^0.0.1",
     "@deepseek-ai/dsh-llm": "^0.0.1",
+    "@deepseek-ai/dsh-paths": "^0.0.1",
     "@deepseek-ai/dsh-session": "^0.0.1",
     "@deepseek-ai/dsh-session-telemetry": "^0.0.1",
     "cordis": "^4.0.0-rc.7"
   },
   "devDependencies": {
     "@cordisjs/plugin-loader": "workspace:^",
+    "@deepseek-ai/dsh-brand": "workspace:^",
     "@deepseek-ai/dsh-invariants": "workspace:^",
     "@deepseek-ai/dsh-llm": "workspace:^",
+    "@deepseek-ai/dsh-paths": "workspace:^",
     "@deepseek-ai/dsh-session": "workspace:^",
     "@deepseek-ai/dsh-session-telemetry": "workspace:^",
     "cordis": "^4.0.0-rc.7"
diff --git a/packages/telemetry/session-telemetry-otel/src/index.ts b/packages/telemetry/session-telemetry-otel/src/index.ts
index 85dd75f275..55caa1037b 100644
--- a/packages/telemetry/session-telemetry-otel/src/index.ts
+++ b/packages/telemetry/session-telemetry-otel/src/index.ts
@@ -17,6 +17,7 @@ import z from 'schemastery'
 import type { Context } from 'cordis'
 import { Telemetry, TelemetryCoordinator, type TelemetryRecord, type TelemetrySeverity } from '@deepseek-ai/dsh-session-telemetry'
 import { APP_IDENTITY } from '@deepseek-ai/dsh-llm'
+import { getOrCreateAnonymousUserId } from './user-id.ts'
 import {
   BatchLogRecordProcessor,
   LoggerProvider,
@@ -118,6 +119,10 @@ export class TelemetryOtel extends Telemetry {
       resource: resourceFromAttributes({
         'service.name': APP_IDENTITY.product,
         'service.version': APP_IDENTITY.version,
+        // OTel semconv's standard user attribute, carried once per export
+        // batch on the Resource rather than per record: the collector
+        // aggregates by Resource, and the id is process-stable anyway.
+        'user.id': getOrCreateAnonymousUserId(),
       }),
       processors: [
         new BatchLogRecordProcessor({
diff --git a/packages/telemetry/session-telemetry-otel/src/user-id.ts b/packages/telemetry/session-telemetry-otel/src/user-id.ts
new file mode 100644
index 0000000000..f06d9856fe
--- /dev/null
+++ b/packages/telemetry/session-telemetry-otel/src/user-id.ts
@@ -0,0 +1,103 @@
+/**
+ * Per-harness-home anonymous user id for the OTel Resource.
+ *
+ * The id is a random UUID persisted as a bare line in `.userid` inside the
+ * harness home resolved by {@link resolveDshHome} (`$DSH_HOME` > `~/.dsh`),
+ * and never derived from the hostname, network address, git remote, or any
+ * other identifying source — a derived id would make "anonymous" a fiction.
+ * The id is scoped to the harness home, not the machine: every process
+ * sharing one `$DSH_HOME` reports the same id, and deleting the file simply
+ * mints a fresh identity on the next launch (loss is accepted by design).
+ * This identity belongs to the OTel feed alone; the dsh-sdk launcher
+ * telemetry keeps its own separate store.
+ *
+ * Reads and writes are synchronous so the backend constructor can call this
+ * on its boot path, and the result is memoized per resolved file path: one
+ * process touches the disk once, and a file deleted mid-run keeps the
+ * process's id until the next launch.
+ *
+ * @module @deepseek-ai/dsh-session-telemetry-otel/user-id
+ */
+
+import { randomUUID } from 'node:crypto'
+import { mkdirSync, readFileSync, writeFileSync } from 'node:fs'
+import { dirname, join } from 'node:path'
+import type { Branded } from '@deepseek-ai/dsh-brand'
+import { resolveDshHome } from '@deepseek-ai/dsh-paths'
+
+/** A harness-home-scoped anonymous user id (random UUID v4). */
+export type AnonymousUserId = Branded<'AnonymousUserId'>
+
+/** File inside the harness home storing the id: a bare UUID line, no wrapper format. */
+export const USER_ID_FILE_NAME = '.userid'
+
+const UUID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i
+
+/** Ambient seams for locating and generating the id; every field has a default. */
+export interface AnonymousUserIdOptions {
+  /** Environment consulted for `DSH_HOME`; defaults to `process.env`. */
+  env?: NodeJS.ProcessEnv
+  /** UUID generator; defaults to `crypto.randomUUID` (test seam). */
+  randomUUID?: () => string
+}
+
+/** Process-lifetime memo keyed by resolved file path, so distinct test homes never share an id. */
+const memo = new Map<string, AnonymousUserId>()
+
+/** Read a valid persisted id from the file, or `undefined` when absent/corrupt. */
+function readPersistedId(file: string): AnonymousUserId | undefined {
+  let text: string
+  try {
+    text = readFileSync(file, 'utf8')
+  } catch {
+    // Absent or unreadable: the caller mints and persists a fresh id.
+    return undefined
+  }
+  const value = text.trim()
+  return UUID_PATTERN.test(value) ? (value as AnonymousUserId) : undefined
+}
+
+/**
+ * Return the harness home's anonymous user id, creating and persisting one on
+ * first use. A concurrent first launch is settled by an exclusive-create
+ * write: the loser rereads the winner's id. (A reread landing in the winner's
+ * narrow create-to-write window can still yield two per-process ids for that
+ * run; the next launch converges on the persisted one.) Persistence is
+ * best-effort — a write failure (read-only home) still returns a usable id
+ * for the current run so telemetry is never blocked.
+ * @param options - home-location and UUID-generation seams.
+ * @returns the stable per-harness-home anonymous user id.
+ */
+export function getOrCreateAnonymousUserId(options: AnonymousUserIdOptions = {}): AnonymousUserId {
+  const file = join(resolveDshHome(undefined, options.env ?? process.env), USER_ID_FILE_NAME)
+  const cached = memo.get(file)
+  if (cached !== undefined) return cached
+
+  let id = readPersistedId(file)
+  if (id === undefined) {
+    const generate = options.randomUUID ?? randomUUID
+    const created = generate() as AnonymousUserId
+    try {
+      mkdirSync(dirname(file), { recursive: true })
+      writeFileSync(file, `${created}\n`, { encoding: 'utf8', flag: 'wx' })
+      id = created
+    } catch {
+      // A wx refusal (EEXIST) covers both a concurrent winner and a
+      // pre-existing corrupt file: the reread adopts a valid winner, and an
+      // invalid reread falls through to the overwrite path. Non-EEXIST
+      // failures (read-only home) land there too, accepted best-effort below.
+      id = readPersistedId(file)
+      if (id === undefined) {
+        try {
+          writeFileSync(file, `${created}\n`, 'utf8')
+        } catch {
+          // Best-effort persistence: keep the fresh id in memory even when the
+          // home is unwritable, so this run still reports a consistent id.
+        }
+        id = created
+      }
+    }
+  }
+  memo.set(file, id)
+  return id
+}
diff --git a/packages/telemetry/session-telemetry-otel/tests/otel.spec.ts b/packages/telemetry/session-telemetry-otel/tests/otel.spec.ts
index cccb90ed43..6be7f81977 100644
--- a/packages/telemetry/session-telemetry-otel/tests/otel.spec.ts
+++ b/packages/telemetry/session-telemetry-otel/tests/otel.spec.ts
@@ -5,11 +5,15 @@
  * for the default-exported Service class.
  */
 
-import { afterEach, describe, expect, it } from 'vitest'
+import { afterAll, afterEach, beforeAll, describe, expect, it } from 'vitest'
 import { createServer, type Server } from 'node:http'
 import { once } from 'node:events'
+import { mkdtempSync, rmSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
 import { gunzipSync } from 'node:zlib'
 import { Context } from 'cordis'
+import { getOrCreateAnonymousUserId } from '../src/user-id.ts'
 import Loader from '@cordisjs/plugin-loader'
 import SessionStore, { SessionId } from '@deepseek-ai/dsh-session'
 import TelemetryOtel, { Config } from '../src/index.ts'
@@ -37,6 +41,21 @@ interface OtlpLogsRequest {
 
 const servers: Server[] = []
 
+// The backend resolves the harness home's anonymous user id at construction;
+// pin DSH_HOME to a temp dir so the suite never touches the ambient ~/.dsh.
+let tempHome: string
+let previousDshHome: string | undefined
+beforeAll(() => {
+  tempHome = mkdtempSync(join(tmpdir(), 'dsh-otel-home-'))
+  previousDshHome = process.env.DSH_HOME
+  process.env.DSH_HOME = tempHome
+})
+afterAll(() => {
+  if (previousDshHome === undefined) delete process.env.DSH_HOME
+  else process.env.DSH_HOME = previousDshHome
+  rmSync(tempHome, { recursive: true, force: true })
+})
+
 afterEach(async () => {
   for (const server of servers.splice(0)) {
     server.close()
@@ -104,6 +123,7 @@ describe('TelemetryOtel wire', () => {
 
     const resource = first.body.resourceLogs[0]!.resource.attributes
     expect(resource).toContainEqual({ key: 'service.name', value: { stringValue: 'deepseek-harness' } })
+    expect(resource).toContainEqual({ key: 'user.id', value: { stringValue: getOrCreateAnonymousUserId() } })
 
     const records = allRecords(captures)
     const ledger = records.filter(r => r.scope === '@deepseek-ai/dsh-session-telemetry-otel')
diff --git a/packages/telemetry/session-telemetry-otel/tests/user-id.spec.ts b/packages/telemetry/session-telemetry-otel/tests/user-id.spec.ts
new file mode 100644
index 0000000000..f4d9505546
--- /dev/null
+++ b/packages/telemetry/session-telemetry-otel/tests/user-id.spec.ts
@@ -0,0 +1,107 @@
+import { chmodSync, existsSync, mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { afterEach, describe, expect, it } from 'vitest'
+import {
+  USER_ID_FILE_NAME,
+  getOrCreateAnonymousUserId,
+} from '../src/user-id.ts'
+
+const dirs: string[] = []
+
+function tempHome(): string {
+  const dir = mkdtempSync(join(tmpdir(), 'dsh-userid-'))
+  dirs.push(dir)
+  return dir
+}
+
+afterEach(() => {
+  for (const dir of dirs.splice(0)) {
+    chmodSync(dir, 0o700)
+    rmSync(dir, { recursive: true, force: true })
+  }
+})
+
+const UUID = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i
+
+describe('getOrCreateAnonymousUserId', () => {
+  it('creates, persists, and returns a bare UUID line on first use', () => {
+    const home = tempHome()
+    const id = getOrCreateAnonymousUserId({ env: { DSH_HOME: home } })
+    expect(id).toMatch(UUID)
+    expect(readFileSync(join(home, USER_ID_FILE_NAME), 'utf8')).toBe(`${id}\n`)
+  })
+
+  it('creates the home directory when missing', () => {
+    const home = join(tempHome(), 'nested', 'home')
+    const id = getOrCreateAnonymousUserId({ env: { DSH_HOME: home } })
+    expect(readFileSync(join(home, USER_ID_FILE_NAME), 'utf8')).toBe(`${id}\n`)
+  })
+
+  it('returns the persisted id on subsequent calls, tolerating surrounding whitespace', () => {
+    const home = tempHome()
+    const existing = '01234567-89ab-4cde-8f01-23456789abcd'
+    writeFileSync(join(home, USER_ID_FILE_NAME), `  ${existing}\n\n`, 'utf8')
+    expect(getOrCreateAnonymousUserId({ env: { DSH_HOME: home } })).toBe(existing)
+  })
+
+  it('overwrites a corrupt file with a fresh id', () => {
+    const home = tempHome()
+    writeFileSync(join(home, USER_ID_FILE_NAME), 'not-a-uuid\n', 'utf8')
+    const id = getOrCreateAnonymousUserId({ env: { DSH_HOME: home } })
+    expect(id).toMatch(UUID)
+    expect(readFileSync(join(home, USER_ID_FILE_NAME), 'utf8')).toBe(`${id}\n`)
+  })
+
+  it('adopts a concurrent winner: exclusive create loses to an id written after the initial read', () => {
+    const home = tempHome()
+    const winner = 'aaaaaaaa-bbbb-4ccc-8ddd-eeeeeeeeeeee'
+    const file = join(home, USER_ID_FILE_NAME)
+    // The generator seam runs between the initial read (absent) and the wx
+    // write, so planting the winner here simulates the concurrent first launch.
+    const id = getOrCreateAnonymousUserId({
+      env: { DSH_HOME: home },
+      randomUUID: () => {
+        writeFileSync(file, `${winner}\n`, 'utf8')
+        return 'ffffffff-0000-4000-8000-000000000000'
+      },
+    })
+    expect(id).toBe(winner)
+  })
+
+  it('returns a usable id when the home is unwritable, without persisting', () => {
+    const home = tempHome()
+    const blocked = join(home, 'blocked')
+    mkdirSync(blocked)
+    chmodSync(blocked, 0o500)
+    const id = getOrCreateAnonymousUserId({ env: { DSH_HOME: blocked } })
+    expect(id).toMatch(UUID)
+    expect(existsSync(join(blocked, USER_ID_FILE_NAME))).toBe(false)
+  })
+
+  it('memoizes per resolved home for the process lifetime: one read, deletion-proof', () => {
+    const home = tempHome()
+    const first = getOrCreateAnonymousUserId({ env: { DSH_HOME: home } })
+    rmSync(join(home, USER_ID_FILE_NAME))
+    expect(getOrCreateAnonymousUserId({ env: { DSH_HOME: home } })).toBe(first)
+  })
+
+  it('keeps distinct homes on distinct ids', () => {
+    const a = getOrCreateAnonymousUserId({ env: { DSH_HOME: tempHome() } })
+    const b = getOrCreateAnonymousUserId({ env: { DSH_HOME: tempHome() } })
+    expect(a).not.toBe(b)
+  })
+
+  it('reads process.env by default', () => {
+    const home = tempHome()
+    const previous = process.env.DSH_HOME
+    process.env.DSH_HOME = home
+    try {
+      const id = getOrCreateAnonymousUserId()
+      expect(readFileSync(join(home, USER_ID_FILE_NAME), 'utf8')).toBe(`${id}\n`)
+    } finally {
+      if (previous === undefined) delete process.env.DSH_HOME
+      else process.env.DSH_HOME = previous
+    }
+  })
+})
diff --git a/packages/telemetry/session-telemetry-otel/tsconfig.json b/packages/telemetry/session-telemetry-otel/tsconfig.json
index 9512133cf7..8acfe15b33 100644
--- a/packages/telemetry/session-telemetry-otel/tsconfig.json
+++ b/packages/telemetry/session-telemetry-otel/tsconfig.json
@@ -26,6 +26,12 @@
     {
       "path": "../session-telemetry"
     },
+    {
+      "path": "../../util/brand"
+    },
+    {
+      "path": "../../util/paths"
+    },
     {
       "path": "../../support/invariants"
     }
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 96a8df6f8f..b6a697dbb7 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -5199,12 +5199,18 @@ importers:
       '@cordisjs/plugin-loader':
         specifier: workspace:^
         version: link:../../../vendor/loader
+      '@deepseek-ai/dsh-brand':
+        specifier: workspace:^
+        version: link:../../util/brand
       '@deepseek-ai/dsh-invariants':
         specifier: workspace:^
         version: link:../../support/invariants
       '@deepseek-ai/dsh-llm':
         specifier: workspace:^
         version: link:../../llm/llm
+      '@deepseek-ai/dsh-paths':
+        specifier: workspace:^
+        version: link:../../util/paths
       '@deepseek-ai/dsh-session':
         specifier: workspace:^
         version: link:../../core/session