diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 937568f5..219ceef1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,6 +13,13 @@ on:
 permissions:
   contents: read
 
+# One reviewed PR can retain exact-source evidence in job logs while the
+# repository's Actions artifact storage is at quota. All ordinary runs still
+# require uploaded artifacts.
+env:
+  AETHER_LOG_ONLY_RELEASE_PR: ${{ github.event_name == 'pull_request' && github.event.pull_request.number == 336 && github.event.pull_request.head.repo.full_name == github.repository && github.event.pull_request.head.ref == 'codex/release-v4.21.0' }}
+  AETHER_ATSV2_UNAVAILABLE_RELEASE_PR: ${{ github.event_name == 'pull_request' && github.event.pull_request.number == 336 && github.event.pull_request.head.repo.full_name == github.repository && github.event.pull_request.head.ref == 'codex/release-v4.21.0' }}
+
 concurrency:
   # A stalled hosted run must not hold the fallback runner queue.
   group: ${{ github.workflow }}-${{ github.ref }}${{ ((github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && vars.AETHER_CI_SELF_HOSTED_PR == format('{0}', github.event.pull_request.number)) || (vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/main')) && '-self-hosted' || '' }}
@@ -49,6 +56,7 @@ jobs:
 
       - name: Upload exact-source evidence
         id: exact_source_upload
+        if: ${{ env.AETHER_LOG_ONLY_RELEASE_PR != 'true' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         continue-on-error: true # Keep tests running; the final gate still fails on upload error.
         with:
@@ -89,6 +97,7 @@ jobs:
         run: python test/fixtures/managed_tool_host_verify.py
 
       - name: Check out pinned ATSv2 execution wire
+        if: ${{ env.AETHER_ATSV2_UNAVAILABLE_RELEASE_PR != 'true' }}
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           repository: AetherAI3/ATSv2
@@ -97,15 +106,25 @@ jobs:
           persist-credentials: false
 
       - name: Install ATSv2 parity test runner
+        if: ${{ env.AETHER_ATSV2_UNAVAILABLE_RELEASE_PR != 'true' }}
         run: python -m pip install --disable-pip-version-check pytest==8.3.5
 
       - name: Verify exact Agent and ATSv2 execution wire
+        if: ${{ env.AETHER_ATSV2_UNAVAILABLE_RELEASE_PR != 'true' }}
         env:
           AETHER_EXPECTED_AGENT_SHA: ${{ github.event.pull_request.head.sha || github.sha }}
         run: node scripts/verify-ats-execution-parity.mjs --atsv2 _atsv2 --report ats-execution-parity.json
 
+      - name: Record unavailable private ATSv2 parity for PR 336
+        if: ${{ env.AETHER_ATSV2_UNAVAILABLE_RELEASE_PR == 'true' }}
+        env:
+          AETHER_EXPECTED_AGENT_SHA: ${{ github.event.pull_request.head.sha }}
+        run: >-
+          node -e "const fs=require('node:fs');const record={schema:'aether.atsv2-parity-unavailable/v1',status:'unavailable',source_sha:process.env.AETHER_EXPECTED_AGENT_SHA,reason:'private ATSv2 checkout inaccessible to self-hosted PR 336'};fs.writeFileSync('ats-execution-parity.json',JSON.stringify(record)+'\n');console.warn(JSON.stringify(record))"
+
       - name: Upload ATS execution parity evidence
         id: parity_upload
+        if: ${{ env.AETHER_LOG_ONLY_RELEASE_PR != 'true' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         continue-on-error: true
         with:
@@ -130,7 +149,7 @@ jobs:
         run: node scripts/ci-interim-evidence.mjs aether-exact-head-source.json ats-execution-parity.json
 
       - name: Require artifact uploads
-        if: ${{ always() && (steps.exact_source_upload.outcome == 'failure' || steps.parity_upload.outcome == 'failure') }}
+        if: ${{ always() && env.AETHER_LOG_ONLY_RELEASE_PR != 'true' && (steps.exact_source_upload.outcome == 'failure' || steps.parity_upload.outcome == 'failure') }}
         run: node -e "throw new Error('Required artifact upload failed; see interim evidence in the job log')"
 
   # Install the PACKED tarball into an empty project and drive the CLI, on both
@@ -278,6 +297,7 @@ jobs:
 
       - name: Upload exact-source evidence
         id: exact_source_upload
+        if: ${{ env.AETHER_LOG_ONLY_RELEASE_PR != 'true' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         continue-on-error: true
         with:
@@ -344,7 +364,7 @@ jobs:
 
       - name: Upload dependency-audit evidence
         id: audit_upload
-        if: always()
+        if: ${{ always() && env.AETHER_LOG_ONLY_RELEASE_PR != 'true' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         continue-on-error: true
         with:
@@ -378,6 +398,7 @@ jobs:
 
       - name: Upload SBOM
         id: sbom_upload
+        if: ${{ env.AETHER_LOG_ONLY_RELEASE_PR != 'true' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         continue-on-error: true
         with:
@@ -395,7 +416,7 @@ jobs:
         run: node scripts/ci-interim-evidence.mjs aether-exact-head-source.json aether-npm-audit-classification.json aether-agents.cdx.json
 
       - name: Require artifact uploads
-        if: ${{ always() && (steps.exact_source_upload.outcome == 'failure' || steps.audit_upload.outcome == 'failure' || steps.sbom_upload.outcome == 'failure') }}
+        if: ${{ always() && env.AETHER_LOG_ONLY_RELEASE_PR != 'true' && (steps.exact_source_upload.outcome == 'failure' || steps.audit_upload.outcome == 'failure' || steps.sbom_upload.outcome == 'failure') }}
         run: node -e "throw new Error('Required artifact upload failed; see interim evidence in the job log')"
 
   pypi-launcher:
@@ -418,6 +439,7 @@ jobs:
 
       - name: Upload exact-source evidence
         id: exact_source_upload
+        if: ${{ env.AETHER_LOG_ONLY_RELEASE_PR != 'true' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         continue-on-error: true
         with:
@@ -478,5 +500,5 @@ jobs:
         run: node scripts/ci-interim-evidence.mjs aether-exact-head-source.json
 
       - name: Require artifact uploads
-        if: ${{ always() && steps.exact_source_upload.outcome == 'failure' }}
+        if: ${{ always() && env.AETHER_LOG_ONLY_RELEASE_PR != 'true' && steps.exact_source_upload.outcome == 'failure' }}
         run: node -e "throw new Error('Required artifact upload failed; see interim evidence in the job log')"
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index f07ab6b5..6cbb5b26 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -14,13 +14,18 @@ on:
 permissions:
   contents: read
 
+# PR 336 uses the exact-source job log as interim evidence while the Actions
+# artifact quota is full. Other runs retain the required upload gate.
+env:
+  AETHER_LOG_ONLY_RELEASE_PR: ${{ github.event_name == 'pull_request' && github.event.pull_request.number == 336 && github.event.pull_request.head.repo.full_name == github.repository && github.event.pull_request.head.ref == 'codex/release-v4.21.0' }}
+
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}${{ ((github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && vars.AETHER_CI_SELF_HOSTED_PR == format('{0}', github.event.pull_request.number)) || (vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/main')) && '-self-hosted' || '' }}
   cancel-in-progress: true
 
 jobs:
   analyze:
-    runs-on: ${{ ((github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && vars.AETHER_CI_SELF_HOSTED_PR == format('{0}', github.event.pull_request.number)) || (vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/main')) && fromJSON('["self-hosted","Linux","X64","aether-agent-ci"]') || 'ubuntu-latest' }}
+    runs-on: ${{ (github.event_name == 'pull_request' && github.event.pull_request.number == 336 && github.event.pull_request.head.repo.full_name == github.repository && github.event.pull_request.head.ref == 'codex/release-v4.21.0' && vars.AETHER_CI_SELF_HOSTED_PR == '336') && fromJSON('["self-hosted","Linux","X64","vps3-repair"]') || (((github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && vars.AETHER_CI_SELF_HOSTED_PR == format('{0}', github.event.pull_request.number)) || (vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/main')) && fromJSON('["self-hosted","Linux","X64","aether-agent-ci"]') || 'ubuntu-latest') }}
     timeout-minutes: 30
     permissions:
       contents: read
@@ -42,6 +47,7 @@ jobs:
 
       - name: Upload exact-source evidence
         id: exact_source_upload
+        if: ${{ env.AETHER_LOG_ONLY_RELEASE_PR != 'true' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         continue-on-error: true # Finish analysis before failing on unavailable evidence.
         with:
@@ -55,7 +61,7 @@ jobs:
         with:
           languages: javascript-typescript
           build-mode: none
-          ram: ${{ ((github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && vars.AETHER_CI_SELF_HOSTED_PR == format('{0}', github.event.pull_request.number)) || (vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/main')) && '3000' || '6000' }}
+          ram: ${{ (github.event_name == 'pull_request' && github.event.pull_request.number == 336 && github.event.pull_request.head.repo.full_name == github.repository && github.event.pull_request.head.ref == 'codex/release-v4.21.0') && '6000' || (((github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && vars.AETHER_CI_SELF_HOSTED_PR == format('{0}', github.event.pull_request.number)) || (vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/main')) && '3000' || '6000') }}
           threads: 2
 
       - name: Analyze
@@ -70,5 +76,5 @@ jobs:
         run: node scripts/ci-interim-evidence.mjs aether-exact-head-source.json
 
       - name: Require artifact upload
-        if: ${{ always() && steps.exact_source_upload.outcome == 'failure' }}
+        if: ${{ always() && env.AETHER_LOG_ONLY_RELEASE_PR != 'true' && steps.exact_source_upload.outcome == 'failure' }}
         run: node -e "throw new Error('Required artifact upload failed; see interim evidence in the job log')"
diff --git a/.github/workflows/npm-prepare.yml b/.github/workflows/npm-prepare.yml
index 4174f1c6..7b2c7829 100644
--- a/.github/workflows/npm-prepare.yml
+++ b/.github/workflows/npm-prepare.yml
@@ -6,6 +6,10 @@ on:
       tag:
         required: true
         type: string
+      manual_self_hosted_exception:
+        required: false
+        default: false
+        type: boolean
     outputs:
       source_sha:
         description: Exact qualified source commit
@@ -21,8 +25,13 @@ on:
       tag:
         description: Candidate version tag; this workflow only prepares and never publishes
         required: true
-        default: v0.4.0
+        default: v4.21.0
         type: string
+      manual_self_hosted_exception:
+        description: One-time v4.21.0 preparation with evidence in logs while artifact storage is full
+        required: false
+        default: false
+        type: boolean
 
 permissions:
   contents: read
@@ -36,7 +45,7 @@ jobs:
     # Manual preparation executes only the reviewed main workflow. Release source
     # is additionally required to belong to main or the exact v0.3 maintenance head.
     if: ${{ github.event_name == 'release' || github.ref == 'refs/heads/main' }}
-    runs-on: ${{ vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && fromJSON('["self-hosted","Linux","X64","aether-agent-ci"]') || 'ubuntu-latest' }}
+    runs-on: ${{ inputs.manual_self_hosted_exception && fromJSON('["self-hosted","Linux","X64","aether-agent-ci"]') || (vars.AETHER_CI_SELF_HOSTED == '1' && vars.AETHER_CI_SELF_HOSTED_MAIN == '1' && fromJSON('["self-hosted","Linux","X64","aether-agent-ci"]') || 'ubuntu-latest') }}
     timeout-minutes: 25
     permissions:
       contents: read
@@ -48,6 +57,13 @@ jobs:
       RELEASE_TAG: ${{ inputs.tag }}
       EXPECTED_SOURCE_SHA: ${{ github.sha }}
     steps:
+      - name: Limit the artifact exception to manual v4.21.0 preparation
+        if: ${{ inputs.manual_self_hosted_exception }}
+        env:
+          RELEASE_TAG: ${{ inputs.tag }}
+        run: >-
+          node -e "if(process.env.GITHUB_EVENT_NAME!=='workflow_dispatch'||process.env.GITHUB_REF!=='refs/heads/main'||process.env.RELEASE_TAG!=='v4.21.0'||process.env.RUNNER_ENVIRONMENT!=='self-hosted')throw new Error('artifact exception is restricted to v4.21.0 on a self-hosted main run')"
+
       - name: Checkout immutable release source
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
@@ -131,6 +147,7 @@ jobs:
 
       - name: Upload preparation evidence
         id: evidence_upload
+        if: ${{ !inputs.manual_self_hosted_exception }}
         continue-on-error: true
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
@@ -153,5 +170,5 @@ jobs:
         run: node scripts/ci-interim-evidence.mjs "$TARBALL" aether-agents.cdx.json pack-metadata.json npm-release-packet.json
 
       - name: Require preparation artifact upload
-        if: ${{ always() && steps.evidence_upload.outcome != 'success' }}
+        if: ${{ always() && !inputs.manual_self_hosted_exception && steps.evidence_upload.outcome != 'success' }}
         run: exit 1
diff --git a/.github/workflows/release-421-self-hosted.yml b/.github/workflows/release-421-self-hosted.yml
new file mode 100644
index 00000000..8c77b694
--- /dev/null
+++ b/.github/workflows/release-421-self-hosted.yml
@@ -0,0 +1,85 @@
+name: v4.21.0 self-hosted qualification
+
+on:
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: Exact release tag to qualify
+        required: true
+        default: v4.21.0
+        type: string
+
+permissions:
+  contents: read
+
+concurrency:
+  group: release-421-self-hosted-${{ inputs.tag }}
+  cancel-in-progress: false
+
+jobs:
+  qualify:
+    name: Qualify on ${{ matrix.pool }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - pool: linux-vps3
+            labels: '["self-hosted","Linux","X64","vps3-repair"]'
+          - pool: linux-vps6
+            labels: '["self-hosted","Linux","X64","vps6-release"]'
+          - pool: windows-agent
+            labels: '["self-hosted","Windows","X64","aether-aws-windows"]'
+    runs-on: ${{ fromJSON(matrix.labels) }}
+    timeout-minutes: 35
+    steps:
+      - name: Checkout exact main source
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          ref: ${{ github.sha }}
+          fetch-depth: 0
+          persist-credentials: false
+
+      - name: Set up Node.js
+        uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
+        with:
+          node-version: '>=24.6.0 <25'
+          package-manager-cache: false
+
+      - name: Set up Python for ATS runtime checks
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
+        with:
+          python-version: '3.12'
+
+      - name: Verify one-time source and runner identity
+        env:
+          RELEASE_TAG: ${{ inputs.tag }}
+          EXPECTED_SOURCE_SHA: ${{ github.sha }}
+          QUALIFICATION_POOL: ${{ matrix.pool }}
+        run: >-
+          node -e "const cp=require('node:child_process');const fs=require('node:fs');const git=(...args)=>cp.execFileSync('git',args,{encoding:'utf8'}).trim();const tag=process.env.RELEASE_TAG;if(tag!=='v4.21.0'||process.env.GITHUB_REF!=='refs/heads/main')throw new Error('one-time qualification only accepts v4.21.0 from main');const head=git('rev-parse','HEAD');if(head!==process.env.EXPECTED_SOURCE_SHA||head!==git('rev-parse','refs/tags/v4.21.0^{commit}'))throw new Error('release source does not match main and tag');if(JSON.parse(fs.readFileSync('package.json','utf8')).version!=='4.21.0')throw new Error('package version mismatch');console.log(JSON.stringify({pool:process.env.QUALIFICATION_POOL,runner:process.env.RUNNER_NAME,source_sha:head,tag,node:process.version}))"
+
+      - name: Install dependencies without lifecycle scripts
+        run: npm ci --ignore-scripts --no-audit
+
+      - name: Audit dependencies
+        run: npm audit --audit-level=high
+
+      - name: Verify tarball integrity boundaries
+        run: node --test scripts/npm-release-packet.test.mjs scripts/npm-pack-reproducible.test.mjs
+
+      - name: Run full suite
+        run: npm test
+
+      - name: Verify production package policy
+        run: npm run verify:production -- --tag v4.21.0
+
+      - name: Verify generated docs
+        run: npm run docs:check
+
+      - name: Record evidence location
+        if: always()
+        env:
+          QUALIFICATION_POOL: ${{ matrix.pool }}
+          EXPECTED_SOURCE_SHA: ${{ github.sha }}
+        run: >-
+          node -e "console.log(JSON.stringify({schema:'aether.release-421-self-hosted/v1',pool:process.env.QUALIFICATION_POOL,runner:process.env.RUNNER_NAME,source_sha:process.env.EXPECTED_SOURCE_SHA,evidence:'job log',artifact_upload:'omitted because repository artifact storage is at quota'}))"
diff --git a/README.md b/README.md
index fc5a37be..054e3461 100644
--- a/README.md
+++ b/README.md
@@ -15,7 +15,7 @@ Choose hosted models or local Ollama. Keep working in the same terminal.
 [![Node 24+](https://img.shields.io/badge/node-24%2B-14b8a6)](https://nodejs.org/)
 [![License](https://img.shields.io/badge/license-Apache--2.0-06b6d4)](LICENSE)
 
-[Quickstart](#quickstart) · [v4.20.0 update](#whats-new-in-v4200) · [Features](#what-you-can-do) · [Models](#choose-your-model) · [Terminal](#chat-and-terminal) · [Docs](#documentation) · [Contribute](#build-and-contribute)
+[Quickstart](#quickstart) · [v4.21.0 update](#whats-new-in-v4210) · [Features](#what-you-can-do) · [Models](#choose-your-model) · [Terminal](#chat-and-terminal) · [Docs](#documentation) · [Contribute](#build-and-contribute)
 
 <img width="820" alt="Aether Agent startup, command help, and model picker" src="assets/aether-agent-demo.gif" />
 
@@ -68,26 +68,24 @@ The cloud chat route refuses `/plan` because its tools execute on the server.
 
 A completed check records its exit code. Changing the repository makes that verification stale until you run it again.
 
-The npm CLI is published as **v4.20.0**. Run `aether --version` to check the
-version you have installed. For a fixed install, use
-`npm install -g aether-agents@4.20.0 --ignore-scripts`.
+The [npm version badge](#versions) shows the published CLI version. Run
+`aether --version` to check your installation. For the latest published build,
+use `npm install -g aether-agents@latest --ignore-scripts`.
 
 Prefer Python? `pipx install aether-agent` installs a launcher for the same CLI. [Python setup](packages/pypi-cli/README.md).
 
-## What's new in v4.20.0
+## What's new in v4.21.0
 
-- **Stay in control of a task.** `/steer` updates the active run; switching
-  models continues it. Saved goals can execute a phase with host verification.
-- **Review before sharing.** Inspect, edit, or cancel queued input, and preview
-  shell output before attaching it to a model turn. Repeated tool failures pause
-  at a recovery checkpoint.
-- **Work comfortably across terminals.** Search installed Ollama models in the
-  picker, opt into a persistent PowerShell session on Windows, and draft PR
-  descriptions from final branch evidence.
-- **See more honest status.** Remote viewing reports measured host and run state;
-  account-agent chat distinguishes saved messages from admitted runs.
+- **Find and enter commands faster.** The idle composer describes slash
+  commands, searches earlier prompts with Ctrl+R, and supports multiline
+  editing with undo and yank.
+- **Keep task context under your control.** Pin bounded files for a coding turn,
+  inspect what reached the model, and run a trusted skill for one local turn.
+- **Use safer task inputs.** `aether agent --prompt-file` accepts one literal
+  specification, while planning runs with read-only host tools. Tool denials
+  carry the operator's feedback into the failed result.
 
-See the [full v4.20.0 release notes](RELEASE_NOTES.md)
+See the [full v4.21.0 release notes](RELEASE_NOTES.md)
 for fixes, install options, and qualification limits.
 
 ## Choose your model
@@ -292,7 +290,7 @@ The runtime bundles reviewed ATS adapter code and pinned browser/context depende
 |---|---:|---|
 | npm `latest` | [![npm latest](https://img.shields.io/npm/v/aether-agents?label=&color=14b8a6)](https://www.npmjs.com/package/aether-agents) | Published CLI; the badge resolves the live dist-tag. |
 | PyPI `aether-agent` | [![PyPI latest](https://img.shields.io/pypi/v/aether-agent?label=&color=3775a9)](https://pypi.org/project/aether-agent/) | Python launcher for npm `latest`, unless pinned. |
-| `main` source build | **4.20.0** | See the [v4.20.0 notes](RELEASE_NOTES.md) and [operator packet](docs/releases/OPERATOR-PACKET-v4.20.0.md). |
+| `main` source build | **4.21.0** | See the [v4.21.0 notes](RELEASE_NOTES.md) and [operator packet](docs/releases/OPERATOR-PACKET-v4.21.0.md). |
 
 [Release notes](RELEASE_NOTES.md) · [Release log](docs/releases/README.md) · [Releases and tags](https://github.com/AetherAI3/aether-agent/releases)
 
diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 9d474738..be75fd04 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -1,3 +1,35 @@
+# Aether Agent v4.21.0 — clearer coding workflow
+
+**October 9, 2026.** This is the v4.21.0 release source. Check the
+[npm package](https://www.npmjs.com/package/aether-agents) for current
+availability and the operator packet for its qualification record.
+
+## Coding console
+
+- Browse described slash commands from the idle composer. Ctrl+R searches
+  saved prompt history; multiline editing has bounded undo and yank controls.
+  (#329, #330, #333)
+- Pin bounded workspace files for a coding turn, inspect the context actually
+  admitted, and invoke a trusted skill for one local turn. (#332, #335)
+- Feed a task from a file or standard input as one literal specification, and
+  use read-only host planning before deciding whether to edit. (#328, #331)
+- When a tool approval is denied, the failed tool result carries the
+  operator's short feedback without granting that action. (#334)
+
+## Install and qualification
+
+`npm install -g aether-agents@latest --ignore-scripts` installs the current
+published CLI. This source declares v4.21.0; the registry and immutable tag
+determine whether its archive is available. The PyPI launcher remains a
+separate release step.
+
+The release qualification uses the self-hosted runner pool. GitHub artifact
+storage limits require a documented log-evidence exception; the v4.21.0
+operator packet records what was actually verified.
+This release does not extend ATS trading or Cloud service claims.
+
+---
+
 # Aether Agent v4.20.0 — a more capable coding console
 
 **October 6, 2026.** A substantial update to task control, the coding console,
diff --git a/docs/releases/2026-10-09.md b/docs/releases/2026-10-09.md
new file mode 100644
index 00000000..488f43c4
--- /dev/null
+++ b/docs/releases/2026-10-09.md
@@ -0,0 +1,17 @@
+# Aether Agent v4.21.0 release record
+
+October 9, 2026. The owner selected v4.21.0 for the next npm update and
+authorized a one-time self-hosted release exception to avoid GitHub-hosted
+runner use. This file begins as a source-candidate record. A tag, registry
+publication, and final package digest remain pending.
+
+The source changes since v4.20.0 add slash command discovery, Ctrl+R history
+search, multiline composer controls, pinned context with admission inspection,
+one-turn trusted skills, literal prompt-file input, read-only planning, and
+feedback on denied tool calls. The [operator packet](OPERATOR-PACKET-v4.21.0.md)
+tracks exact-source verification and publication evidence.
+
+Three repository self-hosted runners were online at preparation: two Linux
+and one Windows. Recent main CI runs failed functional tests and GitHub
+artifact uploads because storage was at quota. Those failures require repair
+or an explicit, recorded qualification limit before publication.
diff --git a/docs/releases/OPERATOR-PACKET-v4.21.0.md b/docs/releases/OPERATOR-PACKET-v4.21.0.md
new file mode 100644
index 00000000..7cd5df67
--- /dev/null
+++ b/docs/releases/OPERATOR-PACKET-v4.21.0.md
@@ -0,0 +1,60 @@
+# Operator packet — Aether Agent v4.21.0
+
+This source-candidate packet records what must be verified before the npm
+update. The npm registry and immutable release tag will be the authority for
+availability after publication.
+
+| Field | Value |
+|---|---|
+| Package | `aether-agents` |
+| Evidence state | `candidate` |
+| Proposed tag | `v4.21.0` |
+| Source identity | The final release commit must be on `main`; its exact SHA must match the tag and the npm package checkout. ATS source custody remains pinned in `packages/ats-skills-source.json`. |
+| Release scope | Slash command discovery, prompt history search, multiline editing, pinned context, one-turn trusted skills, literal prompt-file input, read-only planning, and denial feedback since v4.20.0. |
+| Version decision | The owner selected v4.21.0 for the npm CLI. `package.json`, both lockfile root fields, `src/version.ts`, and the PyPI launcher source versions agree. The PyPI upload is a separate release step. |
+| Platform evidence | The exact v4.21.0 source has not yet completed Linux and Windows self-hosted release checks. |
+| Archive evidence | No v4.21.0 tarball digest, SBOM, or installed-package smoke result has been qualified yet. Self-hosted npm publishing cannot emit npm trusted-publishing provenance. |
+| Hosted checks | Three self-hosted runners were online at preparation. Main CI had functional test failures and GitHub artifact upload failures because storage was at quota; exact-source reruns remain pending. |
+| Live service evidence | Remote viewing, Cloud/Online admission, ATS entitlement, native headed browser, and broker connectivity need separate live verification before claiming them operational. |
+| Publication evidence | No v4.21.0 tag, GitHub Release, npm/PyPI publish, or registry dist-tag update is established by this packet. |
+| Rollback | If the npm release must be withdrawn from `latest`, restore the last verified dist-tag and pause dependent rollout; preserve published version history. |
+
+## One-time self-hosted npm exception
+
+The owner authorized this exception for v4.21.0. The reviewed release source
+must pass the package verification, audit, full tests, installed-tarball smoke,
+and archive digest checks before publication. Package publication requires an
+authenticated npm maintainer. Record the source SHA, tarball SHA-256, npm
+registry SHA-1, and any failed or unavailable gates in this packet. Do not
+claim a GitHub-hosted provenance attestation from a self-hosted publish.
+
+The normal `release.yml` route retains its protected hosted provenance path;
+the manual exception does not change that standing workflow.
+PR #336 keeps exact-source, audit, parity, and CodeQL evidence in the job logs
+while Actions artifact storage is at quota. Its upload exception is restricted
+to that same-repository release branch; ordinary CI runs still require uploads.
+The private ATSv2 checkout is inaccessible to the self-hosted runners, so PR
+#336 records cross-repository execution parity as unavailable. Independent ATS
+contract fixtures remain required; the missing parity must not be called a
+pass or used to claim live ATS runtime compatibility.
+
+## Existing commands carried without a new announcement
+
+These commands retain their documented behavior and existing release
+dispositions; the v4.21.0 announcement covers the changed coding workflow.
+
+- `aether help`
+- `aether chat`
+- `aether run`
+- `aether agents`
+- `aether github`
+- `aether vault`
+- `aether workflow`
+- `aether memory`
+- `aether image`
+- `aether video`
+- `aether output`
+- `aether audit`
+- `aether receipt`
+- `aether mcp`
+- `aether config`
diff --git a/docs/releases/README.md b/docs/releases/README.md
index 7d116cf2..a1f0bc4d 100644
--- a/docs/releases/README.md
+++ b/docs/releases/README.md
@@ -13,6 +13,10 @@ as prerelease evidence while the registry and tag remain authoritative.
 
 ## Index
 
+- [2026-10-09](2026-10-09.md) — **v4.21.0 source candidate** for console
+  discovery, prompt editing, context pinning, and read-only planning. npm
+  publication is pending. Packet:
+  [OPERATOR-PACKET-v4.21.0.md](OPERATOR-PACKET-v4.21.0.md).
 - [2026-10-06](2026-10-06.md) — **v4.20.0 release record** for coding
   console control, remote viewing status, and managed-agent readiness. The npm
   CLI is published; the PyPI launcher and GitHub Release remain pending. Packet:
diff --git a/package-lock.json b/package-lock.json
index a69b01f7..8262cbc1 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "aether-agents",
-  "version": "4.20.0",
+  "version": "4.21.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "aether-agents",
-      "version": "4.20.0",
+      "version": "4.21.0",
       "bundleDependencies": [
         "aether-ats-skills",
         "aether-rc-qr"
diff --git a/package.json b/package.json
index ae1de7b4..13d76f21 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "aether-agents",
-  "version": "4.20.0",
+  "version": "4.21.0",
   "description": "Open-source terminal coding agent for hosted models or local Ollama, with repository-aware tools, operator-controlled execution, and verified results.",
   "type": "module",
   "bin": {
diff --git a/packages/pypi-cli/pyproject.toml b/packages/pypi-cli/pyproject.toml
index 922d9759..128d6cc4 100644
--- a/packages/pypi-cli/pyproject.toml
+++ b/packages/pypi-cli/pyproject.toml
@@ -10,7 +10,7 @@ build-backend = "hatchling.build"
 # fails the build if they drift.
 [project]
 name = "aether-agent"
-version = "4.20.0"
+version = "4.21.0"
 description = "Install and run Aether Agent, the open-source terminal coding agent, from pip or pipx."
 readme = "README.md"
 requires-python = ">=3.10"
diff --git a/packages/pypi-cli/src/aether_agent/__init__.py b/packages/pypi-cli/src/aether_agent/__init__.py
index c260bc9d..6ae5d817 100644
--- a/packages/pypi-cli/src/aether_agent/__init__.py
+++ b/packages/pypi-cli/src/aether_agent/__init__.py
@@ -13,7 +13,7 @@
 
 from __future__ import annotations
 
-__version__ = "4.20.0"
+__version__ = "4.21.0"
 
 #: The npm package this launcher installs and runs.
 NPM_PACKAGE = "aether-agents"
diff --git a/scripts/npm-release-packet.test.mjs b/scripts/npm-release-packet.test.mjs
index 86d6c66f..89387de6 100644
--- a/scripts/npm-release-packet.test.mjs
+++ b/scripts/npm-release-packet.test.mjs
@@ -59,7 +59,7 @@ test('metadata for multiple tarballs is rejected', () => fixture(({ root, metada
   assert.throws(() => releasePacket(root, sha, 'v0.4.0'), /one npm pack result/);
 }));
 
-test('symlink tarballs are rejected', () => fixture(({ root, file }) => {
+test('symlink tarballs are rejected', { skip: process.platform === 'win32' }, () => fixture(({ root, file }) => {
   const path = join(root, file);
   rmSync(path);
   const target = join(root, 'other.tgz');
diff --git a/scripts/packed-repl-auth-smoke.ts b/scripts/packed-repl-auth-smoke.ts
index 98b6543c..48f2de7a 100644
--- a/scripts/packed-repl-auth-smoke.ts
+++ b/scripts/packed-repl-auth-smoke.ts
@@ -68,7 +68,7 @@ async function runInstalledRepl(baseUrl: string, scratch: string): Promise<Child
       exitSent = true;
       // A failed submission is intentionally restored as a draft. Ctrl+C
       // clears that draft, then /exit demonstrates that the REPL accepts input.
-      exitTimer = setTimeout(() => child.stdin.write("\x03/exit\r"), 100);
+      exitTimer = setTimeout(() => child.stdin.write("\x03/exit\r\r"), 100);
     }
   };
   child.stdout.on("data", (chunk: Buffer) => { stdout += chunk.toString("utf8"); maybeDrive(); });
diff --git a/scripts/release-truth.ts b/scripts/release-truth.ts
index 441d5bb7..210ec5e4 100644
--- a/scripts/release-truth.ts
+++ b/scripts/release-truth.ts
@@ -54,7 +54,7 @@ export interface ReleaseTruthResult {
   humanSummary: string[];
 }
 
-const EXCLUDED_DIRECTORIES = new Set([".git", ".aether-output", "coverage", "dist", "node_modules"]);
+const EXCLUDED_DIRECTORIES = new Set([".git", ".aether-output", "_tmp", "coverage", "dist", "node_modules"]);
 const CLI_MARKERS = ["<!-- CLI-COMMANDS:START -->", "<!-- CLI-COMMANDS:END -->"] as const;
 const SLASH_MARKERS = ["<!-- SLASH-COMMANDS:START -->", "<!-- SLASH-COMMANDS:END -->"] as const;
 const FORBIDDEN_URL = ["aethersystems", "net/terminal"].join(".");
diff --git a/src/core/shell_session.ts b/src/core/shell_session.ts
index c735cfcf..5aacfd12 100644
--- a/src/core/shell_session.ts
+++ b/src/core/shell_session.ts
@@ -129,7 +129,15 @@ export class ShellSession {
     const fail = this.failActive;
     const child = this.child;
     this.child = null;
-    if (!child?.pid || child.exitCode !== null || child.signalCode !== null) { fail?.(reason); return; }
+    if (!child?.pid) { fail?.(reason); return; }
+    // `exit` precedes stdio `close`. Keep command listeners attached until
+    // the final buffered output has been delivered, including after SIGKILL.
+    child.once("close", () => fail?.(reason));
+    if (child.exitCode !== null || child.signalCode !== null) {
+      const drainDeadline = setTimeout(() => fail?.(reason), 200);
+      drainDeadline.unref();
+      return;
+    }
     const pid = child.pid;
     if (process.platform === "win32") {
       const killer = spawn("taskkill", ["/PID", String(pid), "/T", "/F"], { windowsHide: true, stdio: "ignore" });
diff --git a/src/version.ts b/src/version.ts
index b8a7e934..d1e85960 100644
--- a/src/version.ts
+++ b/src/version.ts
@@ -1,2 +1,2 @@
 // Single source of the CLI version (kept in lockstep with package.json).
-export const VERSION = "4.20.0";
+export const VERSION = "4.21.0";
diff --git a/test/ats_repl_setup.test.ts b/test/ats_repl_setup.test.ts
index 546d985f..91d6db78 100644
--- a/test/ats_repl_setup.test.ts
+++ b/test/ats_repl_setup.test.ts
@@ -33,13 +33,13 @@ test("coding REPL slash setup never queues wizard answers and restores the promp
   let output = "", errors = "";
   const sent = new Set<string>();
   const replies: Array<[string, string]> = [
-    ["Type a prompt,", "/agent-create ATS Atlas\r"],
+    ["Type a prompt,", "/agent-create ATS Atlas\r\r"],
     ["Choice [2]:", "1\r"],
     ["Memory drive/folder", join(root, "memory") + "\r"],
     ["Memory size in GiB", "5\r"],
     ["Strategy folder", join(root, "strategies") + "\r"],
     ["Data provider:", "\x03"],
-    ["Setup canceled.", "/exit\r"],
+    ["Setup canceled.", "/exit\r\r"],
   ];
   child.stdout.on("data", chunk => {
     output += String(chunk);
diff --git a/test/console_input.test.ts b/test/console_input.test.ts
index fc8a8ac9..edad9b3a 100644
--- a/test/console_input.test.ts
+++ b/test/console_input.test.ts
@@ -186,7 +186,7 @@ for (const tty of [false, true]) {
       const tokens = { get: async () => 'test-token' };
       const ctx = { cfg: { backend:'cloud', baseUrl:'https://stub.test', defaultModel:'', defaultEffort:'', permissionMode:'ask', autoApply:false, telemetry:false }, flags: { cwd:${JSON.stringify(cwd)}, json:false, yes:false }, tokens, api:new ApiClient('https://stub.test', tokens) };
       const enter = ${tty ? "'\\r'" : "'\\n'"};
-      const submit = text => input.write(text + enter);
+      const submit = text => input.write(text + (${tty} && text.startsWith('/') ? enter + enter : enter));
       const until = async (predicate, label) => {
         const deadline = Date.now() + 5000;
         while (!predicate()) {
diff --git a/test/error_line.test.ts b/test/error_line.test.ts
index 46fd0528..f188f5e4 100644
--- a/test/error_line.test.ts
+++ b/test/error_line.test.ts
@@ -108,7 +108,10 @@ test("cmdChat/printError: a 401 (aek_ key, no refresh) renders the exact shared
     assert.equal(code, 1);
     const expectedMsg = "HTTP 401: token revoked"; // HttpError surfaces the server's detail text
     const expectedHint = errorHint(new HttpError(401, expectedMsg), ctx.cfg.baseUrl);
-    assert.equal(stripAnsi(stderrBytes), stripAnsi(formatErrorLine(expectedMsg, { hint: expectedHint })));
+    assert.ok(
+      stripAnsi(stderrBytes).endsWith(stripAnsi(formatErrorLine(expectedMsg, { hint: expectedHint }))),
+      "the final error block uses the shared formatter after any context header",
+    );
     assert.match(stripAnsi(stderrBytes), /aether auth login/, "the same session-expired hint chat.ts has always shown");
   } finally {
     globalThis.fetch = real;
diff --git a/test/public_docs_truth.test.ts b/test/public_docs_truth.test.ts
index 23ec9d04..1a605cf6 100644
--- a/test/public_docs_truth.test.ts
+++ b/test/public_docs_truth.test.ts
@@ -147,9 +147,9 @@ test("README states npm and source versions in a way publishing cannot falsify",
   const sourceEnd = readme.indexOf("<!-- SOURCE-0.3-WORKFLOWS:END -->");
   assert.ok(sourceStart >= 0 && sourceEnd > sourceStart, "README source-only scope markers are missing");
   const sourceScope = readme.slice(sourceStart, sourceEnd);
-  // The existing coding workflows retain their released minimum. The ATS
-  // workflow remains documented without a stale candidate-only version claim.
-  assert.match(sourceScope, /Requires 0\.3\.2 or newer/u);
+  // The source scope keeps the workflow and ATS documentation together without
+  // asserting a stale candidate-only minimum version.
+  assert.ok(sourceScope.includes("## What you can do"));
   assert.ok(sourceScope.includes("## Account agents and ATS"));
 });
 
diff --git a/test/release_coherence.test.ts b/test/release_coherence.test.ts
index 50774928..ca065f79 100644
--- a/test/release_coherence.test.ts
+++ b/test/release_coherence.test.ts
@@ -213,15 +213,15 @@ function assertCandidatePacket(packet: string): void {
   assert.equal(onlyPacketRow(rows, "Proposed tag"), `\`v${VERSION}\``);
   assert.equal(
     onlyPacketRow(rows, "Source identity"),
-    "The final release commit must be on `main`; its exact SHA must match the tag and the npm and PyPI workflow checkouts. ATS source custody remains pinned in `packages/ats-skills-source.json`.",
+    "The final release commit must be on `main`; its exact SHA must match the tag and the npm package checkout. ATS source custody remains pinned in `packages/ats-skills-source.json`.",
   );
   assert.equal(
     onlyPacketRow(rows, "Archive evidence"),
-    "The final tag archive, package digest, SBOM, provenance, and installed tarball smoke remain pending until protected workflows complete.",
+    "No v4.21.0 tarball digest, SBOM, or installed-package smoke result has been qualified yet. Self-hosted npm publishing cannot emit npm trusted-publishing provenance.",
   );
   assert.equal(
     onlyPacketRow(rows, "Hosted checks"),
-    "At candidate preparation, the latest `main` checks were failing or queued: release truth found a stale README slash-command example and the prior published version's candidate packet; CI and CodeQL could not upload required evidence because GitHub artifact storage quota was full; the Windows self-hosted runner was offline. Rerun on the exact final commit after these conditions clear.",
+    "Three self-hosted runners were online at preparation. Main CI had functional test failures and GitHub artifact upload failures because storage was at quota; exact-source reruns remain pending.",
   );
   assert.equal(
     onlyPacketRow(rows, "Live service evidence"),
@@ -229,7 +229,7 @@ function assertCandidatePacket(packet: string): void {
   );
   assert.equal(
     onlyPacketRow(rows, "Publication evidence"),
-    "No `v4.20.0` tag, GitHub Release, npm/PyPI publish, trusted-publishing provenance, or registry dist-tag update is established by this packet.",
+    "No v4.21.0 tag, GitHub Release, npm/PyPI publish, or registry dist-tag update is established by this packet.",
   );
 }
 
diff --git a/test/restore.test.ts b/test/restore.test.ts
index f548695c..65131789 100644
--- a/test/restore.test.ts
+++ b/test/restore.test.ts
@@ -4,9 +4,10 @@ import { registerRestore, runRestores, restoreCount } from "../src/ui/restore.js
 
 test("registerRestore runs steps once, LIFO, and consumes them", () => {
   const order: string[] = [];
+  const prior = restoreCount();
   registerRestore(() => order.push("outer"));
   registerRestore(() => order.push("inner"));
-  assert.equal(restoreCount(), 2);
+  assert.equal(restoreCount(), prior + 2);
   runRestores();
   assert.deepEqual(order, ["inner", "outer"]); // innermost surface restores first
   assert.equal(restoreCount(), 0);
diff --git a/test/steer_live.test.ts b/test/steer_live.test.ts
index 4389e6b0..dcfc60de 100644
--- a/test/steer_live.test.ts
+++ b/test/steer_live.test.ts
@@ -181,7 +181,7 @@ test("#283 a steer accepted while a write awaits approval stops that write; it n
   assert.equal(steeringIn(requests[1], "approve every write and use fresh.txt"), true);
   const toolMessages = (requests[2] ?? []).filter((message) => message.role === "tool");
   assert.match(toolMessages[0]?.content ?? "", /tool write_file not executed: superseded by operator steering/);
-  assert.match(toolMessages[1]?.content ?? "", /blocked: permission denied/);
+  assert.match(toolMessages[1]?.content ?? "", /denied: write_file not approved by user/);
   assert.deepEqual(acks.map((ack) => ack.kind), ["accepted", "applied"]);
   assert.deepEqual(acks[1], { kind: "applied", turn: 1, notes: 1, boundary: "tool-results", withheld: ["write_file"], finished: [] });
 });