diff --git a/.github/workflows/ci-diagnose.yml b/.github/workflows/ci-diagnose.yml
deleted file mode 100644
index 71b5ceeb..00000000
--- a/.github/workflows/ci-diagnose.yml
+++ /dev/null
@@ -1,93 +0,0 @@
-name: CI Failure Diagnosis
-
-on:
-  workflow_run:
-    workflows: ['CI']
-    types: [completed]
-
-permissions:
-  actions: read
-  contents: read
-  issues: write
-  pull-requests: write
-  id-token: write
-
-concurrency:
-  group: ci-diagnosis-pr-${{ github.event.workflow_run.pull_requests[0].number || github.event.workflow_run.id }}
-  cancel-in-progress: true
-
-jobs:
-  diagnose:
-    if: github.event.workflow_run.conclusion == 'failure'
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v5
-        with:
-          fetch-depth: 1
-
-      - name: Extract run context
-        id: context
-        run: |
-          pr_number="$(jq -r '.workflow_run.pull_requests[0].number // empty' "$GITHUB_EVENT_PATH")"
-          echo "pr_number=${pr_number}" >> "$GITHUB_OUTPUT"
-
-      - name: Skip non-PR runs
-        if: steps.context.outputs.pr_number == ''
-        run: echo "Failed CI run is not attached to a pull request. Skipping PR diagnosis comment."
-
-      - name: Run Claude CI diagnostician
-        if: steps.context.outputs.pr_number != ''
-        uses: anthropics/claude-code-action@v1
-        with:
-          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-          claude_args: |
-            --model opus
-            --max-turns 18
-            --allowedTools "Bash(gh:*)" "WebSearch" "WebFetch"
-          prompt: |
-            You are the CI failure diagnosis agent for this repository.
-
-            Failed run context:
-            - Run ID: ${{ github.event.workflow_run.id }}
-            - Run URL: ${{ github.event.workflow_run.html_url }}
-            - Workflow: ${{ github.event.workflow_run.name }}
-            - Conclusion: ${{ github.event.workflow_run.conclusion }}
-            - Head SHA: ${{ github.event.workflow_run.head_sha }}
-            - PR Number: #${{ steps.context.outputs.pr_number }}
-            - PR URL: https://github.com/${{ github.repository }}/pull/${{ steps.context.outputs.pr_number }}
-
-            Tasks:
-            1. Diagnose what failed by inspecting the failed workflow run and failed jobs using `gh` (jobs, steps, and logs).
-            2. Focus issue types on: lint, typecheck, build, test, link.
-            3. If there are multiple issues, include only actionable root causes (max 3 rows). Collapse duplicates.
-            4. For each actionable issue, include:
-            - file (or nearest path/scope when file is unavailable),
-            - issue type,
-            - concise failure description.
-            5. If the failure is only simple lint/style warnings, keep it brief and generic; do not enumerate every file.
-            6. Avoid noise:
-            - Do not post redundant comments.
-            - Use one comment per PR.
-            - If a comment already exists with marker `<!-- ci-diagnosis:pr-${{ steps.context.outputs.pr_number }} -->`, update it instead of creating a new one.
-            - Do not include stack traces or long command output in comments.
-
-            Post or update a single PR comment on #${{ steps.context.outputs.pr_number }} using this template exactly:
-
-            <!-- ci-diagnosis:pr-${{ steps.context.outputs.pr_number }} -->
-            ### CI Failure Diagnosis
-            - Run: ${{ github.event.workflow_run.html_url }}
-            - Commit: `${{ github.event.workflow_run.head_sha }}`
-
-            | File | Type | What failed |
-            | --- | --- | --- |
-            | ... | lint\|typecheck\|build\|test\|link | ... |
-
-            Rules for output:
-            - Keep the table concise and actionable.
-            - Keep "What failed" to one short sentence.
-            - If only simple lint/style noise exists, use one row:
-              `| (various) | lint | Simple lint/style warnings only. |`
-            - If failure cause is not determinable from logs, use one row with best evidence and next diagnostic step.