Feat/pr description bot

.github/pr-description-template.md

@@ -0,0 +1,31 @@
+## What
+
+A concise summary of what changed.
+
+## Why
+
+The problem, motivation, or behavior being corrected.
+
+## How
+
+Implementation details, grouped by area if useful.
+
+## Tests
+
+List test/typecheck/format evidence inferred from commits, changed files, or workflow status where possible.
+
+## Risks
+
+Call out possible regressions, edge cases, env vars, runtime behavior, or migration concerns.
+
+## Changed Files
+
+Summarize the most important changed files.
+
+## Commits
+
+List commit subjects.
+
+---
+
+_Auto-generated from commits and changed files. This description will be overwritten when new commits are pushed._

.github/workflows/update-pr-description.yml

@@ -0,0 +1,36 @@
+name: Update PR Description
+
+on:
+    pull_request:
+        types: [opened, synchronize]
+
+permissions:
+    contents: read
+    pull-requests: write
+
+jobs:
+    update-pr-description:
+        name: Generate PR description
+        runs-on: ubuntu-latest
+        # Skip dependabot and other bots
+        if: ${{ !contains(fromJson('["dependabot[bot]", "github-actions[bot]"]'), github.event.pull_request.user.login) }}
+
+        steps:
+            - uses: actions/checkout@v6
+              with:
+                  sparse-checkout: scripts/generate-pr-description.ts
+                  sparse-checkout-cone-mode: false
+
+            - uses: oven-sh/setup-bun@v2
+              with:
+                  bun-version: "1.3.11"
+
+            - name: Generate and update PR description
+              env:
+                  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+                  GITHUB_REPOSITORY: ${{ github.repository }}
+                  PR_NUMBER: ${{ github.event.pull_request.number }}
+                  PR_TITLE: ${{ github.event.pull_request.title }}
+                  OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
+                  PR_DESCRIPTION_MODEL: ${{ vars.PR_DESCRIPTION_MODEL }}
+              run: bun scripts/generate-pr-description.ts

README.md

@@ -92,6 +92,7 @@ bun run test:cron:execute-post
 | `X_ACCESS_TOKEN_SECRET` | OAuth1 access token secret                                                             |
 | `X_USER_ID`             | Numeric user ID — required for like, retweet, follow, and webhook self-event filtering |
 | `X_BEARER_TOKEN`        | App-only bearer token (thread context hydration)                                       |
+| `X_HANDLE`              | Agent's X handle without `@` — used to enforce the 1:1 thread depth cap                |
 | `DATABASE_URL`          | Neon Postgres connection string                                                        |
 | `CRON_SECRET`           | **Required.** Shared secret for `/cron/*` routes                                       |