diff --git a/README.md b/README.md
index ffa4330..3e07f96 100644
--- a/README.md
+++ b/README.md
@@ -100,6 +100,16 @@ MIT
 
 ## Changelog
 
+### v0.1.1 — First accumulation release (PR #20)
+
+Ships the merged master work since v0.1.0: ref-tag placement normalization (#12),
+truncated tool-result body preservation (#13), system-prompt alignment with the
+PI rules (#14), reported-usage preference for nudge calculations (#15), smoke
+harness repair (#16), v2 tools registered with the AI-SDK shape + idempotent
+system prompt (#18), and status compressible-range filtering via
+`billion-context-kit` viableRanges with the kit pinned to npm (#19).
+acp-kernel remains 0.0.19 (upgrade deferred).
+
 ### v0.1.0 — Monorepo + dual-shape single package (PR #7, #9)
 
 Initial npm-workspaces monorepo: `@bili/core` (private) + `billion-context-opencode` (published).
diff --git a/devlog/2026-08-15_release-v0.1.1/REQ.md b/devlog/2026-08-15_release-v0.1.1/REQ.md
new file mode 100644
index 0000000..e4c455e
--- /dev/null
+++ b/devlog/2026-08-15_release-v0.1.1/REQ.md
@@ -0,0 +1,27 @@
+# REQ - Release v0.1.1
+
+- Task ID: `2026-08-15_release-v0.1.1`
+- Home Repo: `billion-context-opencode`
+- Created: 2026-08-15
+- Status: Done
+- Priority: P1
+- Owner: ranxianglei
+- References: `packages/billion-context-opencode/package.json`; PR #20
+
+## 1. Background & Problem Statement
+
+- **Context**: npm still serves `billion-context-opencode@0.1.0` while master has accumulated 22 commits since the last release: five contributor fixes (#12–#16), the v2 AI-SDK tool shape (#18), and the viability filter + kit npm pin (#19).
+- **Current behavior (symptom)**: users installing from npm miss the ref-tag normalization, truncated tool-result preservation, reported-usage nudges, and viable-range filtering.
+- **Expected behavior**: `billion-context-opencode@0.1.1` on npm containing all merged master work.
+
+## 2. Requirements
+
+- R1: `packages/billion-context-opencode/package.json` version 0.1.0 → 0.1.1 (the only published package; `@bili/core` stays private).
+- R2: `acp-kernel` stays at 0.0.19 this release — the 0.0.19→0.0.24 jump crosses the prompts-interface + truncation API surface and is deferred to a dedicated PR.
+- R3: README changelog gains a `### v0.1.1` entry (required by check-pr.sh when the version changes).
+
+## 3. Acceptance Criteria
+
+- AC1: workspace typecheck clean, 54/54 tests, build green.
+- AC2: pr-validation passes (devlog REQ+WORKLOG present; README changelog updated).
+- AC3: merge of the release branch triggers the Release workflow (tag v0.1.1 + npm publish).
diff --git a/devlog/2026-08-15_release-v0.1.1/WORKLOG.md b/devlog/2026-08-15_release-v0.1.1/WORKLOG.md
new file mode 100644
index 0000000..a480779
--- /dev/null
+++ b/devlog/2026-08-15_release-v0.1.1/WORKLOG.md
@@ -0,0 +1,26 @@
+# WORKLOG - Release v0.1.1
+
+- Task ID: `2026-08-15_release-v0.1.1`
+- Home Repo: `billion-context-opencode`
+- Status: Done
+- Updated: 2026-08-15
+
+## 1. Summary
+
+- **What was done**: version bump of the single published package (`billion-context-opencode` 0.1.0 → 0.1.1) carrying all merged master work since the initial release, plus the mandatory devlog and README changelog entries.
+
+## 2. Changes
+
+- `packages/billion-context-opencode/package.json`: version 0.1.1.
+- `devlog/2026-08-15_release-v0.1.1/{REQ,WORKLOG}.md`: this devlog.
+- `README.md`: `### v0.1.1` changelog entry (ships #12–#16, #18, #19).
+
+## 3. Verification
+
+- `npm run typecheck` (workspaces): clean.
+- `npm test`: 54/54 pass.
+- `npm run build`: ESM build success (dist/index.js + sourcemap).
+
+## 4. Notes / Follow-ups
+
+- acp-kernel upgrade (0.0.19 → 0.0.24) deliberately deferred: 5-version jump crosses prompts-interface + truncation API surface; deserves its own PR with the e2e harness.
diff --git a/package-lock.json b/package-lock.json
index 2aaeba1..0bf4331 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2098,7 +2098,7 @@
       }
     },
     "packages/billion-context-opencode": {
-      "version": "0.1.0",
+      "version": "0.1.1",
       "license": "MIT",
       "dependencies": {
         "acp-kernel": "0.0.19"
diff --git a/packages/billion-context-opencode/package.json b/packages/billion-context-opencode/package.json
index 8f9c91c..aba1884 100644
--- a/packages/billion-context-opencode/package.json
+++ b/packages/billion-context-opencode/package.json
@@ -1,6 +1,6 @@
 {
   "name": "billion-context-opencode",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "description": "ACP (Active Context Pruning) compression adapter for opencode — one package that loads on both opencode V1 (experimental.chat.* hooks) and V2 (Plugin.define). Model-driven context management via acp-kernel: bili_compress / bili_decompress / bili_search / bili_status.",
   "type": "module",
   "main": "./dist/index.js",