diff --git a/docs/development/non-container.md b/docs/development/non-container.md
index f60b933..33a5483 100644
--- a/docs/development/non-container.md
+++ b/docs/development/non-container.md
@@ -15,9 +15,9 @@ The workspace is a pnpm monorepo with three package groups:
 
 | Group | Path | Purpose |
 | --- | --- | --- |
-| `apps/` | `apps/server` (`@personal-blog/server`) | Public server application. Serves the application health endpoint (E00-S02-T03); the Fastify 5 application shell lands in a later story. |
+| `apps/` | `apps/server` (`@personal-blog/server`) | Public server application. Serves the application health endpoint (E00-S02-T03) gated on the startup migration run (E00-S03-T06); the Fastify 5 application shell lands in a later story. |
 | `packages/` | `packages/core` (`@personal-blog/core`) | Application core (site identity, content primitives). Bootstrap placeholder. |
-| `packages/` | `packages/database-postgres` (`@personal-blog/database-postgres`) | PostgreSQL database adapter package. Single owner of the `pg`/Kysely driver imports (E00-S03-T02); the migration ledger (`schema_migrations`, E00-S03-T03), the migration advisory lock (E00-S03-T04) and the migration runner with its failure diagnostic (E00-S03-T05) are implemented here. |
+| `packages/` | `packages/database-postgres` (`@personal-blog/database-postgres`) | PostgreSQL database adapter package. Single owner of the `pg`/Kysely driver imports (E00-S03-T02); the migration ledger (`schema_migrations`, E00-S03-T03), the migration advisory lock (E00-S03-T04) and the migration runner with its failure diagnostic (E00-S03-T05) are implemented here. The server depends on this package to run the startup migrations behind its readiness gate (E00-S03-T06). |
 | `extensions/` | `extensions/example` (`@personal-blog/example-extension`) | Example extension exercising the `extensions/` group. Bootstrap placeholder. |
 
 A dependency-boundary rule (`dependency-boundaries.json`, enforced by
@@ -94,10 +94,16 @@ compiled application entrypoint. Two things to know:
    compiled artifact in `dist/`, it does not compile first.
 2. Since [E00-S02-T03], `apps/server` serves the **application health
    endpoint**: starting it opens an HTTP server on port 3000 answering
-   `GET /health` with HTTP 200 and `{"status":"ok"}`, so the process stays up.
-   The real Fastify 5 application shell — which turns this into the full
-   serving API — lands in a later story; the `start` command shape stays the
-   same once it does.
+   `GET /health`, so the process stays up. Since [E00-S03-T06] the endpoint
+   is the **readiness probe**: when a `DATABASE_URL` is configured, the app
+   runs the startup migrations before reporting ready — `GET /health` answers
+   HTTP 503 with `{"status":"not ready"}` while the run is in flight and HTTP
+   200 with `{"status":"ok"}` only after it completes. With **no
+   `DATABASE_URL`** (this local non-container path) there is no migration run
+   to wait for, so the server reports ready immediately and `GET /health`
+   answers 200 `{"status":"ok"}` from the start. The real Fastify 5
+   application shell — which turns this into the full serving API — lands in
+   a later story; the `start` command shape stays the same once it does.
 
 To run the compiled output of any other workspace package directly: