update: README with new PR comment format, spec mode, live demo link

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: infracore

README.md

@@ -4,51 +4,61 @@ Fork this repo, push a breaking API change, and see Delimit catch it in CI.
 
 ## What's in the box
 
-- `openapi.yaml` -- a Pet Store API with 4 endpoints
-- `openapi-changed.yaml` -- the same spec with breaking changes:
+- `openapi.yaml` — a Pet Store API with 4 endpoints
+- `openapi-changed.yaml` — the same spec with 5 breaking changes:
   - `GET /pets/{petId}` removed
   - `DELETE /pets/{petId}` removed
   - `Pet.id` type changed from `string` to `integer`
   - `Pet.tag` field removed
   - `Pet.status` enum value `pending` removed
-- `.github/workflows/delimit.yml` -- runs the Delimit action on every push/PR
+- `.github/workflows/delimit.yml` — runs the Delimit action on every push/PR
 
 ## Try it
 
 1. Fork this repo
-2. Push any commit (or just trigger Actions manually)
-3. Watch CI fail:
+2. Push any commit (or trigger Actions manually)
+3. On a PR, Delimit posts a comment like this:
 
-```
-::error title=Delimit::Endpoint /pets/{petId} removed
-::error title=Delimit::Field id type changed from string to integer
-```
+> **Breaking API Changes Detected**
+>
+> | Severity | Change | Location |
+> |----------|--------|----------|
+> | Critical | Endpoint removed | `/pets/{petId}` |
+> | Warning | Type changed (string → integer) | `Pet.id` |
+> | Warning | Enum value removed | `Pet.status` |
+>
+> **Semver: MAJOR** — 5 breaking changes, migration guide included
 
-4. On a PR, Delimit posts a comment with a migration guide
+4. In enforce mode, CI fails until the breaking changes are resolved
 
-## Fix the build
+## Use Delimit in your own repo
 
-Delete `openapi-changed.yaml` and update the workflow to compare `openapi.yaml` against itself. Or better -- edit `openapi-changed.yaml` to only add new endpoints and fields. Additive changes pass.
+The simplest setup — auto-detects the base branch and diffs your spec:
 
-## Use Delimit in your own repo
+```yaml
+- uses: delimit-ai/delimit-action@v1
+  with:
+    spec: api/openapi.yaml
+```
+
+Or compare two specific files:
 
 ```yaml
-# .github/workflows/delimit.yml
 - uses: delimit-ai/delimit-action@v1
   with:
     old_spec: openapi.yaml
-    new_spec: openapi.yaml
+    new_spec: openapi-changed.yaml
     mode: enforce
 ```
 
-Point `old_spec` at your base spec and `new_spec` at the changed version. The action detects breaking changes and posts PR comments automatically.
-
-Or use the CLI:
+CLI:
 
 ```
 npx delimit-cli lint openapi.yaml
 ```
 
+No config. No API keys. No account.
+
 ---
 
-[GitHub Action](https://github.com/delimit-ai/delimit-action) | [CLI](https://www.npmjs.com/package/delimit-cli) | [delimit.ai](https://delimit.ai)
+[Delimit](https://delimit.ai) | [GitHub Action](https://github.com/marketplace/actions/delimit-api-governance) | [CLI](https://www.npmjs.com/package/delimit-cli) | [Live Demo](https://github.com/delimit-ai/delimit-action-demo/pull/2)