diff --git a/.changeset/config.json b/.changeset/config.json
new file mode 100644
index 0000000..9a3e346
--- /dev/null
+++ b/.changeset/config.json
@@ -0,0 +1,7 @@
+{
+  "$schema": "https://unpkg.com/@changesets/config@3.1.1/schema.json",
+  "changelog": ["@changesets/changelog-github", { "repo": "expilu/smart-decisions" }],
+  "commit": false,
+  "access": "public",
+  "baseBranch": "main"
+}
diff --git a/.changeset/remove-openai-dependency.md b/.changeset/remove-openai-dependency.md
new file mode 100644
index 0000000..55b7e2c
--- /dev/null
+++ b/.changeset/remove-openai-dependency.md
@@ -0,0 +1,6 @@
+---
+'smart-decisions': minor
+---
+
+Removed the `openai` SDK dependency: the library now talks to the OpenAI-compatible
+endpoint with an in-library HTTP transport.
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..a270b22
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,54 @@
+name: CI
+
+# Pull-request pipeline plus the always-on main baseline. Gate list mirrors
+# `prepublishOnly` exactly: CI green here means a release would pass too.
+# Failed tests land as inline annotations pinned to the changed lines; the
+# coverage bot posts a per-PR comment comparing coverage against main.
+on:
+  pull_request:
+  push:
+    branches: [main]
+
+permissions:
+  contents: read
+  code-quality: write # lets github-code-quality[bot] post coverage on the PR
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        node: [22, 24] # engines: >=22 — test the floor and the current LTS
+
+    steps:
+      - uses: actions/checkout@v4
+        # Pin the PR head SHA so coverage line numbers map onto the diff view.
+        with:
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+          cache: npm
+
+      - run: npm ci
+      - run: npm run lint
+      - run: npm run format:check
+      - run: npm run typecheck
+      - run: npm run build
+      - run: npm run test:coverage
+
+      - name: Upload coverage for PR comment
+        # Sugar, not a gate: coverage thresholds already fail the job via
+        # test:coverage. Upload hiccups (preview feature) must not block merges.
+        if: >-
+          matrix.node == 22 &&
+          github.event_name == 'pull_request' &&
+          !github.event.pull_request.head.repo.fork
+        uses: actions/upload-code-coverage@v1
+        with:
+          file: coverage/cobertura-coverage.xml
+          language: JavaScript
+          label: code-coverage/vitest
+          fail-on-error: false
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 0000000..d96d5bb
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,51 @@
+name: Release
+
+# Two modes, decided by changesets/action:
+#  - pending changesets on main -> opens/updates the "Version Packages" PR
+#    (bumps package.json, rewrites CHANGELOG.md, syncs src/version.ts)
+#  - no pending changesets (a Version Packages PR was just merged)
+#    -> builds, publishes to npm with provenance (OIDC trusted publishing,
+#    no stored token), tags vX.Y.Z, creates the GitHub release from the
+#    CHANGELOG.md section.
+on:
+  push:
+    branches: [main]
+
+concurrency:
+  group: release-${{ github.ref }}
+  cancel-in-progress: false
+
+permissions:
+  contents: write # tag + GitHub release + Version Packages PR
+  pull-requests: write # Version Packages PR
+  id-token: write # npm trusted publishing (OIDC)
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+
+      # npm >= 11.5 is required for OIDC trusted publishing.
+      - run: npm i -g npm@11
+
+      - run: npm ci
+
+      - uses: changesets/action@v1
+        id: changesets
+        with:
+          version: npx changeset version && node ./scripts/sync-version.mjs
+          publish: node ./scripts/release.mjs
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Tag and create GitHub release
+        if: steps.changesets.outputs.published == 'true'
+        run: node ./scripts/github-release.mjs
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/package-lock.json b/package-lock.json
index 7d7a1bb..7245d0f 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -9,6 +9,8 @@
       "version": "0.0.2",
       "license": "MIT",
       "devDependencies": {
+        "@changesets/changelog-github": "^1.0.1",
+        "@changesets/cli": "^3.0.3",
         "@types/node": "^22",
         "@vitest/coverage-v8": "^5.0.2",
         "eslint": "^10.11.0",
@@ -107,6 +109,306 @@
         "keyv": "^5.6.0"
       }
     },
+    "node_modules/@changesets/apply-release-plan": {
+      "version": "8.1.1",
+      "resolved": "https://registry.npmjs.org/@changesets/apply-release-plan/-/apply-release-plan-8.1.1.tgz",
+      "integrity": "sha512-nk2Hbq3M9NeHMdaIRBDvawKrQJzXB9sGyBUE5yWnIKtvdcNCPj75zBekJYr0gTT2ecJH3eFeTrc8eisPImcv0Q==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/config": "^4.0.1",
+        "@changesets/format": "^0.1.2",
+        "@changesets/git": "^4.0.1",
+        "@changesets/should-skip-package": "^1.0.0",
+        "@changesets/types": "^7.0.0",
+        "import-meta-resolve": "^4.2.0",
+        "jsonc-parser": "^3.3.1",
+        "semver": "^7.8.1"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/assemble-release-plan": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/assemble-release-plan/-/assemble-release-plan-7.0.0.tgz",
+      "integrity": "sha512-oEW8BxdA604kGGtDSCiHr5w9Tv4UWe9I2k61IBNZzCOE1kbYaJj4v+lFQNgcEZFkUc2pV/+hASErGDvpJOZCTg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/errors": "^1.0.0",
+        "@changesets/get-dependents-graph": "^3.0.0",
+        "@changesets/should-skip-package": "^1.0.0",
+        "@changesets/types": "^7.0.0",
+        "semver": "^7.8.1"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/changelog-git": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/changelog-git/-/changelog-git-1.0.0.tgz",
+      "integrity": "sha512-3Dst2Ime2Op5nd4XmWJLPIgp11ZFqJqSkVug9izK6TDcIV4YlhPS4ECbEVR+eGI0bk0r1ItogD4j2Oli87bJrA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/types": "^7.0.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/changelog-github": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@changesets/changelog-github/-/changelog-github-1.0.1.tgz",
+      "integrity": "sha512-QUcrV7878yHlWPXXPA6gqSxNKwtVHCd1K22L7ZAoJw2yGy8K4QvjwOStD75+1Q9KD9ZSUgGS94HuYdd7HOVtpA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/get-github-info": "^1.0.1",
+        "@changesets/types": "^7.0.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/cli": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/@changesets/cli/-/cli-3.0.3.tgz",
+      "integrity": "sha512-L1i67bMfkK6iC/kDejuNO4pFgTRcWIObsD6Qof2woP1I4M8tj17DGlcpRaTzTv1DYSP5EMwWdEtR8X0Pj5Jg3Q==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/apply-release-plan": "^8.1.1",
+        "@changesets/assemble-release-plan": "^7.0.0",
+        "@changesets/changelog-git": "^1.0.0",
+        "@changesets/config": "^4.0.1",
+        "@changesets/errors": "^1.0.0",
+        "@changesets/get-dependents-graph": "^3.0.0",
+        "@changesets/git": "^4.0.1",
+        "@changesets/pre": "^3.0.0",
+        "@changesets/read": "^1.0.1",
+        "@changesets/should-skip-package": "^1.0.0",
+        "@changesets/types": "^7.0.0",
+        "@changesets/write": "^1.0.1",
+        "@clack/prompts": "^1.7.0",
+        "@manypkg/get-packages": "^3.1.0",
+        "@pnpm/deps.graph-sequencer": "^1100.0.1",
+        "cac": "^7.0.0",
+        "import-meta-resolve": "^4.2.0",
+        "launch-editor": "^2.14.1",
+        "package-manager-detector": "^1.6.0",
+        "semver": "^7.8.1",
+        "tinyexec": "^1.3.1"
+      },
+      "bin": {
+        "changeset": "bin.js"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26",
+        "npm": ">=10.9.0",
+        "pnpm": ">=10.0.0",
+        "yarn": ">=4.5.2"
+      }
+    },
+    "node_modules/@changesets/config": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/@changesets/config/-/config-4.0.1.tgz",
+      "integrity": "sha512-PxpxSQLQSLDjceAgRq+4FWlU+HflDIw03mmPVipxoQx9xrXFUjmqTy3SE+n/2t+DqPdpPiLWVr5NRiLZvjyLwg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/get-dependents-graph": "^3.0.0",
+        "@changesets/should-skip-package": "^1.0.0",
+        "@changesets/types": "^7.0.0",
+        "@manypkg/get-packages": "^3.1.0",
+        "picomatch": "^4.0.7"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/errors": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/errors/-/errors-1.0.0.tgz",
+      "integrity": "sha512-ElN/mEzn6zmETgjwf5MclCMa9ef59sAR0lfO8VSYIsiRvbC2FbLB/92EoYw10Sl0kGixxHFiJZUSv7dA+YpR8g==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/format": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/@changesets/format/-/format-0.1.2.tgz",
+      "integrity": "sha512-Caez5XtNXCFS/G5bwyav3wuXL0tMxVd2ZGbaumWbzN08tyzO21asCw7JZhNtVsAZDCvDRUzZN+Iit9SyRITSYA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "package-manager-detector": "^1.8.0",
+        "tinyexec": "^1.3.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/get-dependents-graph": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/get-dependents-graph/-/get-dependents-graph-3.0.0.tgz",
+      "integrity": "sha512-ji/t5wFA1zREKXRUePE6Qi+Qu2UgxCeSSGQrphezwvQZrp49B7sJ+8+wvM0tA7zPeSxYKCojDy3WWgrl+s+awg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/types": "^7.0.0",
+        "semver": "^7.8.1"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/get-github-info": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@changesets/get-github-info/-/get-github-info-1.0.1.tgz",
+      "integrity": "sha512-ifLQCky/ZtDgZ4xCiUMjnLZSJ8xk52iIzMJbBBPlZWjr2CiTNTaTDddIVWKicrUAdWuLWL7PUw2fNa1yPwLpIg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "dataloader": "^2.2.3"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/git": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/@changesets/git/-/git-4.0.1.tgz",
+      "integrity": "sha512-6vWpIAC4LkpmlqaIu37ViT5enyd9+uBwAiGqCGhASvkSHBgx4PrtTGXWTMFYpDmZbjgyonyVgMciPrW4MqtJsA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/errors": "^1.0.0",
+        "@changesets/types": "^7.0.0",
+        "@manypkg/get-packages": "^3.1.0",
+        "picomatch": "^4.0.4",
+        "tinyexec": "^1.3.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/parse": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/parse/-/parse-1.0.0.tgz",
+      "integrity": "sha512-P0iaMb9p9CRYZiTgAllEIF9AUMQHIy1G72tKlcIqJp61icZSsKQNiOPdxAMZG8m/DvZwt/oz5xEbTpike//dWg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/types": "^7.0.0",
+        "yaml": "^2.9.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/pre": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/pre/-/pre-3.0.0.tgz",
+      "integrity": "sha512-Zm/6YliV/a2oeWTqHJf6KxLrQwgcK1i/BRDl2m0EKZvbnxV5fG9QRhwJJGshjsZTUTS6dkfURQ2K6aAvgNw/3Q==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/errors": "^1.0.0",
+        "@changesets/types": "^7.0.0",
+        "@manypkg/get-packages": "^3.1.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/read": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@changesets/read/-/read-1.0.1.tgz",
+      "integrity": "sha512-nzvSC6RcTiWf/dsuwZFXpLzGGsRHYCL68U3uHV7srsulU93aVWY7u2GEJiDZ+4GIIElfaW5EqtKC0UHroY+LTQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/git": "^4.0.1",
+        "@changesets/parse": "^1.0.0",
+        "@changesets/types": "^7.0.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/should-skip-package": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/should-skip-package/-/should-skip-package-1.0.0.tgz",
+      "integrity": "sha512-pwqoJmbONn1XgXmZXPEExgAaT+HdZLjALFTDgIm+PnS5KeO2nLtzA2/Q+4aMFY14kFMuXKG30MObhvDzWgzDgg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/types": "^7.0.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/types": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/@changesets/types/-/types-7.0.0.tgz",
+      "integrity": "sha512-c5GoiQyt3pxiXjrWSNoP8/GRf4kG+VnKzovx1OQM8dYYALlSwgedmkPmJ+ZqGxqwg9D3Bkj85Uo4KLd5BN3A0w==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@changesets/write": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@changesets/write/-/write-1.0.1.tgz",
+      "integrity": "sha512-q/ThtP9gcnEP6xlv7LrY26C2mHqdGBti/MmOVngt/M/oIGYkssmQGxPK9WzBNt2juVcH/vml2WQ+ra8LXYOTaA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@changesets/format": "^0.1.1",
+        "@changesets/types": "^7.0.0",
+        "human-id": "^4.2.0"
+      },
+      "engines": {
+        "node": "^22.11 || ^24 || >=26"
+      }
+    },
+    "node_modules/@clack/core": {
+      "version": "1.5.1",
+      "resolved": "https://registry.npmjs.org/@clack/core/-/core-1.5.1.tgz",
+      "integrity": "sha512-iHTrHA8MtVuLl2TfZySmcKv1qO2PoyC9Z7pfSDozEuV5vtY3/wcOPKJXlqJ5Oq2Cx5DDGQGAMVx6HZfRRoVEbQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "fast-wrap-ansi": "^0.2.0",
+        "sisteransi": "^1.0.5"
+      },
+      "engines": {
+        "node": ">= 20.12.0"
+      }
+    },
+    "node_modules/@clack/prompts": {
+      "version": "1.8.1",
+      "resolved": "https://registry.npmjs.org/@clack/prompts/-/prompts-1.8.1.tgz",
+      "integrity": "sha512-dlT1m5e/0yUL0kRNcQn7yGLVThkgbB0Ga/1AmfDDC/8ik6AIiSf2QLQO2zPYvefsHP0aFgxO93cVLCCfDp7kzQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@clack/core": "1.5.1",
+        "fast-string-width": "^3.0.2",
+        "fast-wrap-ansi": "^0.2.0",
+        "sisteransi": "^1.0.5"
+      },
+      "engines": {
+        "node": ">= 20.12.0"
+      }
+    },
     "node_modules/@esbuild/aix-ppc64": {
       "version": "0.28.2",
       "resolved": "https://registry.npmjs.org/@esbuild/aix-ppc64/-/aix-ppc64-0.28.2.tgz",
@@ -774,6 +1076,48 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@manypkg/find-root": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/@manypkg/find-root/-/find-root-3.1.0.tgz",
+      "integrity": "sha512-BcSqCyKhBVZ5YkSzOiheMCV41kqAFptW6xGqYSTjkVTl9XQpr+pqHhwgGCOHQtjDCv7Is6EFyA14Sm5GVbVABA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@manypkg/tools": "^2.1.0"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
+    "node_modules/@manypkg/get-packages": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/@manypkg/get-packages/-/get-packages-3.1.0.tgz",
+      "integrity": "sha512-0TbBVyvPrP7xGYBI/cP8UP+yl/z+HtbTttAD7FMAJgn/kXOTwh5/60TsqP9ZYY710forNfyV0N8P/IE/ujGZJg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@manypkg/find-root": "^3.1.0",
+        "@manypkg/tools": "^2.1.0"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
+    "node_modules/@manypkg/tools": {
+      "version": "2.1.2",
+      "resolved": "https://registry.npmjs.org/@manypkg/tools/-/tools-2.1.2.tgz",
+      "integrity": "sha512-6QEf6yqFbETdwGITKq57aYoPfX/3K8XFNwsAlx0C1M7o8cb79sv1M3w+tWuWvIcSbNqrLF7OD7YpZMVVz335hQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "jju": "^1.4.0",
+        "tinyglobby": "^0.2.13",
+        "yaml": "^2.9.0"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
     "node_modules/@oxc-project/types": {
       "version": "0.151.0",
       "resolved": "https://registry.npmjs.org/@oxc-project/types/-/types-0.151.0.tgz",
@@ -785,6 +1129,19 @@
         "url": "https://github.com/sponsors/oxc-project"
       }
     },
+    "node_modules/@pnpm/deps.graph-sequencer": {
+      "version": "1100.0.1",
+      "resolved": "https://registry.npmjs.org/@pnpm/deps.graph-sequencer/-/deps.graph-sequencer-1100.0.1.tgz",
+      "integrity": "sha512-pOr5+q1fLYKwFN3LAJuGZEnfXDcQ73zqgDHMtGy+K+uIoUqyY+6MeDCWFwfu+4EFuq76I5EPFofoNAI+Bmmq4A==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=22.13"
+      },
+      "funding": {
+        "url": "https://opencollective.com/pnpm"
+      }
+    },
     "node_modules/@rolldown/binding-android-arm-eabi": {
       "version": "1.2.11",
       "resolved": "https://registry.npmjs.org/@rolldown/binding-android-arm-eabi/-/binding-android-arm-eabi-1.2.11.tgz",
@@ -1517,6 +1874,16 @@
         "node": "20 || >=22"
       }
     },
+    "node_modules/cac": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/cac/-/cac-7.0.0.tgz",
+      "integrity": "sha512-tixWYgm5ZoOD+3g6UTea91eow5z6AAHaho3g0V9CNSNb45gM8SmflpAc+GRd1InC4AqN/07Unrgp56Y94N9hJQ==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=20.19.0"
+      }
+    },
     "node_modules/cacheable": {
       "version": "2.5.0",
       "resolved": "https://registry.npmjs.org/cacheable/-/cacheable-2.5.0.tgz",
@@ -1556,6 +1923,13 @@
         "node": ">= 8"
       }
     },
+    "node_modules/dataloader": {
+      "version": "2.2.3",
+      "resolved": "https://registry.npmjs.org/dataloader/-/dataloader-2.2.3.tgz",
+      "integrity": "sha512-y2krtASINtPFS1rSDjacrFgn1dcUuoREVabwlOGOe4SdxenREqwjwjElAdwvbGM7kgZz9a3KVicWR7vcz8rnzA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/debug": {
       "version": "4.4.3",
       "resolved": "https://registry.npmjs.org/debug/-/debug-4.4.3.tgz",
@@ -1850,6 +2224,33 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/fast-string-truncated-width": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/fast-string-truncated-width/-/fast-string-truncated-width-3.0.3.tgz",
+      "integrity": "sha512-0jjjIEL6+0jag3l2XWWizO64/aZVtpiGE3t0Zgqxv0DPuxiMjvB3M24fCyhZUO4KomJQPj3LTSUnDP3GpdwC0g==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/fast-string-width": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/fast-string-width/-/fast-string-width-3.0.2.tgz",
+      "integrity": "sha512-gX8LrtNEI5hq8DVUfRQMbr5lpaS4nMIWV+7XEbXk2b8kiQIizgnlr12B4dA3ZEx3308ze0O4Q1R+cHts8kyUJg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "fast-string-truncated-width": "^3.0.2"
+      }
+    },
+    "node_modules/fast-wrap-ansi": {
+      "version": "0.2.2",
+      "resolved": "https://registry.npmjs.org/fast-wrap-ansi/-/fast-wrap-ansi-0.2.2.tgz",
+      "integrity": "sha512-7F2Fl+TjRSenLqlU3UjSH0iyqopqoZIu7eZVpEirP2g1GtWa2G/ecEmBdgz31+Mxr+ELclgg6sokpSFIQiZ02Q==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "fast-string-width": "^3.0.2"
+      }
+    },
     "node_modules/fdir": {
       "version": "6.5.0",
       "resolved": "https://registry.npmjs.org/fdir/-/fdir-6.5.0.tgz",
@@ -1962,6 +2363,16 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/human-id": {
+      "version": "4.2.1",
+      "resolved": "https://registry.npmjs.org/human-id/-/human-id-4.2.1.tgz",
+      "integrity": "sha512-zPGsiS+dWoTZtZ4AtpA9Y+BdSFSNWvnouNlWNoUFyAM6xHOHmdCvqO3k8AIbdamCOv4gUFUVNPf6rJFfc4UiJw==",
+      "dev": true,
+      "license": "MIT",
+      "bin": {
+        "human-id": "dist/cli.js"
+      }
+    },
     "node_modules/ignore": {
       "version": "5.3.2",
       "resolved": "https://registry.npmjs.org/ignore/-/ignore-5.3.2.tgz",
@@ -1972,6 +2383,17 @@
         "node": ">= 4"
       }
     },
+    "node_modules/import-meta-resolve": {
+      "version": "4.2.0",
+      "resolved": "https://registry.npmjs.org/import-meta-resolve/-/import-meta-resolve-4.2.0.tgz",
+      "integrity": "sha512-Iqv2fzaTQN28s/FwZAoFq0ZSs/7hMAHJVX+w8PZl3cY19Pxk6jFFalxQoIfW2826i/fDLXv8IiEZRIT0lDuWcg==",
+      "dev": true,
+      "license": "MIT",
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/wooorm"
+      }
+    },
     "node_modules/imurmurhash": {
       "version": "0.1.4",
       "resolved": "https://registry.npmjs.org/imurmurhash/-/imurmurhash-0.1.4.tgz",
@@ -2022,6 +2444,13 @@
         "jiti": "lib/jiti-cli.mjs"
       }
     },
+    "node_modules/jju": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/jju/-/jju-1.4.0.tgz",
+      "integrity": "sha512-8wb9Yw966OSxApiCt0K3yNJL8pnNeIv+OEq2YMidz4FKP6nonSRoOXc80iXY4JaN2FC11B9qsNmDsm+ZOfMROA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/js-tokens": {
       "version": "10.0.0",
       "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-10.0.0.tgz",
@@ -2043,6 +2472,13 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/jsonc-parser": {
+      "version": "3.3.1",
+      "resolved": "https://registry.npmjs.org/jsonc-parser/-/jsonc-parser-3.3.1.tgz",
+      "integrity": "sha512-HUgH65KyejrUFPvHFPbqOY0rsFip3Bo5wb4ngvdi1EpCYWUQDC5V+Y7mZws+DLkr4M//zQJoanu1SP+87Dv1oQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/keyv": {
       "version": "5.6.0",
       "resolved": "https://registry.npmjs.org/keyv/-/keyv-5.6.0.tgz",
@@ -2053,6 +2489,17 @@
         "@keyv/serialize": "^1.1.1"
       }
     },
+    "node_modules/launch-editor": {
+      "version": "2.14.1",
+      "resolved": "https://registry.npmjs.org/launch-editor/-/launch-editor-2.14.1.tgz",
+      "integrity": "sha512-QWBrQsMpH7gPr965dsKD/3cKWiNoTjpATQf++Xq63N6sKRGMwlVXz41O1IZTMfZQgBctD/K5Zt06+/I6pP6+HA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "picocolors": "^1.1.1",
+        "shell-quote": "^1.8.4"
+      }
+    },
     "node_modules/levn": {
       "version": "0.4.1",
       "resolved": "https://registry.npmjs.org/levn/-/levn-0.4.1.tgz",
@@ -2492,6 +2939,13 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/package-manager-detector": {
+      "version": "1.8.0",
+      "resolved": "https://registry.npmjs.org/package-manager-detector/-/package-manager-detector-1.8.0.tgz",
+      "integrity": "sha512-yQA4H19AmPEoMUeavPMDIe1higySl/gH/yaQrkT/s07Qp+7pp2hYz30N3z2l5BkjVkF9Ow6o0wjJamm2y7Sn0A==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/path-exists": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/path-exists/-/path-exists-4.0.0.tgz",
@@ -2517,8 +2971,7 @@
       "resolved": "https://registry.npmjs.org/picocolors/-/picocolors-1.1.1.tgz",
       "integrity": "sha512-xceH2snhtb5M9liqDsmEw56le376mTZkEX/jEb/RxNFyegNul7eNslCXP9FDj/Lcu0X8KEyMceP2ntpaHrDEVA==",
       "dev": true,
-      "license": "ISC",
-      "peer": true
+      "license": "ISC"
     },
     "node_modules/picomatch": {
       "version": "4.0.7",
@@ -2690,6 +3143,26 @@
         "node": ">=8"
       }
     },
+    "node_modules/shell-quote": {
+      "version": "1.10.0",
+      "resolved": "https://registry.npmjs.org/shell-quote/-/shell-quote-1.10.0.tgz",
+      "integrity": "sha512-w1aiOKwKuRgtwAReIIj89puqg+I7GvX4IbLrvmhXbzQsj1+Zwi4VO3+fa6ZF91TWSjIxoEkKnMeHcLEODK5ZXA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/sisteransi": {
+      "version": "1.0.5",
+      "resolved": "https://registry.npmjs.org/sisteransi/-/sisteransi-1.0.5.tgz",
+      "integrity": "sha512-bLGGlR1QxBcynn2d5YmDX4MGjlZvy2MRBDRNHLJ8VI6l6+9FUiyTFNJ0IveOSP0bcXgVDPRcfGqA0pjaqUpfVg==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/source-map-js": {
       "version": "1.2.1",
       "resolved": "https://registry.npmjs.org/source-map-js/-/source-map-js-1.2.1.tgz",
@@ -2718,9 +3191,9 @@
       }
     },
     "node_modules/tinyexec": {
-      "version": "1.3.0",
-      "resolved": "https://registry.npmjs.org/tinyexec/-/tinyexec-1.3.0.tgz",
-      "integrity": "sha512-QKAl9m8gWWGHV8jZcPeym6j+XULi6tOf1mT83WYJ4Lk2ytW/uwAWkrP0uFsdoYMdueVJ0qs26wZ+23xeB4ibNQ==",
+      "version": "1.3.1",
+      "resolved": "https://registry.npmjs.org/tinyexec/-/tinyexec-1.3.1.tgz",
+      "integrity": "sha512-GCvB3aoys96IuDFBMcTB46JOR6mdMtAToqwiW8JlWhsoh1mhHi/xn9ss/Dg7N555GiJyEt2qzoG/NHCwM6h1EA==",
       "dev": true,
       "license": "MIT",
       "engines": {
@@ -3055,6 +3528,22 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/yaml": {
+      "version": "2.9.1",
+      "resolved": "https://registry.npmjs.org/yaml/-/yaml-2.9.1.tgz",
+      "integrity": "sha512-3NxN8+78OdzbT7C/WjGsyfPAtJaN3FNDsWxv7Y7mcDsT/oOmgW8BpyQQFFBnvZE3j9Y2Sdz1ULFLezL7Eb2yFw==",
+      "dev": true,
+      "license": "ISC",
+      "bin": {
+        "yaml": "bin.mjs"
+      },
+      "engines": {
+        "node": ">= 14.6"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/eemeli"
+      }
+    },
     "node_modules/yocto-queue": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/yocto-queue/-/yocto-queue-0.1.0.tgz",
diff --git a/package.json b/package.json
index dfaa202..28e122d 100644
--- a/package.json
+++ b/package.json
@@ -7,6 +7,7 @@
     "lint": "eslint .",
     "format": "prettier --write .",
     "format:check": "prettier --check .",
+    "changeset": "changeset",
     "build": "tsc -p tsconfig.build.json",
     "typecheck": "tsc",
     "test": "vitest run",
@@ -45,6 +46,8 @@
     "dist"
   ],
   "devDependencies": {
+    "@changesets/changelog-github": "^1.0.1",
+    "@changesets/cli": "^3.0.3",
     "@types/node": "^22",
     "@vitest/coverage-v8": "^5.0.2",
     "eslint": "^10.11.0",
diff --git a/scripts/github-release.mjs b/scripts/github-release.mjs
new file mode 100644
index 0000000..c43f61d
--- /dev/null
+++ b/scripts/github-release.mjs
@@ -0,0 +1,37 @@
+import { execSync } from 'node:child_process';
+import { mkdtempSync, readFileSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+
+/**
+ * Release-announcement step of the Release workflow. Runs after a successful
+ * npm publish and:
+ *
+ * 1. tags the release commit as vX.Y.Z (repo convention matches the existing
+ *    v0.0.2 tag) and pushes the tag;
+ * 2. extracts this version's section from CHANGELOG.md and creates the GitHub
+ *    release with it as the body — release notes and changelog share one
+ *    source of truth.
+ */
+const { version } = JSON.parse(readFileSync('package.json', 'utf8'));
+const tag = `v${version}`;
+
+execSync(`git tag ${tag}`, { stdio: 'inherit' });
+execSync(`git push origin ${tag}`, { stdio: 'inherit' });
+
+const changelog = readFileSync('CHANGELOG.md', 'utf8');
+const section = changelog
+  .split(/^## /m)
+  .find((s) => s.startsWith(`${version} `) || s.startsWith(`v${version} `));
+
+if (!section) {
+  throw new Error(`No CHANGELOG.md section found for ${version}`);
+}
+
+const notesFile = join(mkdtempSync(join(tmpdir(), 'release-notes-')), 'notes.md');
+writeFileSync(notesFile, `${section.trimEnd()}\n`);
+
+execSync(`gh release create ${tag} --title "${tag}" --notes-file "${notesFile}"`, {
+  stdio: 'inherit',
+});
+console.log(`Created GitHub release ${tag}`);
diff --git a/scripts/release.mjs b/scripts/release.mjs
new file mode 100644
index 0000000..4951ece
--- /dev/null
+++ b/scripts/release.mjs
@@ -0,0 +1,35 @@
+import { execSync } from 'node:child_process';
+import { readFileSync } from 'node:fs';
+
+/**
+ * Publish step of the Release workflow (changesets action's `publish` input).
+ *
+ * - Builds dist/ fresh before publishing.
+ * - Unsets GITHUB_TOKEN from the environment: with it present, npm refuses to
+ *   fall through to OIDC trusted publishing.
+ * - Publishes with --provenance (requires npm >= 11.5 and the Trusted Publisher
+ *   registered on npmjs.com for this repo + workflow).
+ * - Idempotent: skips if the exact version is already on the registry (safe on
+ *   workflow retries).
+ */
+const { name, version } = JSON.parse(readFileSync('package.json', 'utf8'));
+
+const env = { ...process.env };
+delete env.GITHUB_TOKEN;
+
+execSync('npm run build', { stdio: 'inherit' });
+
+let exists = false;
+try {
+  execSync(`npm view ${name}@${version} version`, { env, stdio: 'ignore' });
+  exists = true;
+} catch {
+  exists = false;
+}
+
+if (exists) {
+  console.log(`${name}@${version} is already published — nothing to do.`);
+} else {
+  execSync(`npm publish --provenance --access public`, { env, stdio: 'inherit' });
+  console.log(`Published ${name}@${version}`);
+}
diff --git a/scripts/sync-version.mjs b/scripts/sync-version.mjs
new file mode 100644
index 0000000..117e364
--- /dev/null
+++ b/scripts/sync-version.mjs
@@ -0,0 +1,25 @@
+import { readFileSync, writeFileSync } from 'node:fs';
+
+/**
+ * Keeps src/version.ts in sync with package.json. Runs inside the Version
+ * Packages PR (wired into changesets' `version` step), so the VERSION constant
+ * — shown in the User-Agent of every request — bumps together with the package.
+ *
+ * test/version.test.ts stays the tripwire: if this script is ever skipped,
+ * the version test fails in that same PR.
+ */
+const pkg = JSON.parse(readFileSync('package.json', 'utf8'));
+const path = 'src/version.ts';
+const code = readFileSync(path, 'utf8');
+const updated = code.replace(
+  /export const VERSION = '[^']*';/,
+  `export const VERSION = '${pkg.version}';`,
+);
+
+if (updated === code) {
+  console.error('sync-version: no version literal replaced in src/version.ts.');
+  process.exitCode = 1;
+} else {
+  writeFileSync(path, updated);
+  console.log(`sync-version: src/version.ts -> ${pkg.version}`);
+}
diff --git a/vitest.config.ts b/vitest.config.ts
index 37efada..5f2f3f9 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -7,7 +7,14 @@ export default defineConfig({
       // index.ts is a barrel of re-exports; types/ holds only interface/type
       // declarations, i.e. no executable code to cover.
       exclude: ['src/index.ts', 'src/types/**'],
-      reporter: ['text', 'html'],
+      reporter: [
+        'text',
+        'html',
+        // Machine-readable output consumed by CI: json-summary for the coverage
+        // trend comment, cobertura for actions/upload-code-coverage.
+        'json-summary',
+        'cobertura',
+      ],
       thresholds: { lines: 100, functions: 100, branches: 100, statements: 100 },
     },
   },