document skipped rebuilds and the review concurrency queue

platform/repositories.mdx

@@ -70,10 +70,19 @@ The first completed index makes code context available in [Graphs](/platform/gra
 
 These events never start an index: a push to a non-default branch, a branch deletion, and any push to a repository whose indexing is off.
 
+### When a rebuild is skipped
+
+If the graph already covers the latest default-branch commit, Graphify tells you the rebuild was skipped instead of quietly returning the previous build. Typical messages:
+
+- Enabling indexing when the graph is already current: the repository is on, and nothing was re-indexed.
+- **Reindex** soon after a successful rebuild of the same commit: `index_rebuild_debounced` (409), with when you can try again. The graph already reflects that commit.
+
+While a rebuild runs for an unchanged commit, the published graph stays available.
+
 | Code | Status | What it means |
 | --- | --- | --- |
 | `repository_disabled` | 409 | "Enable the repository before re-indexing." Turn **Indexing** back on. |
-| `index_rebuild_debounced` | 409 | A rebuild was requested moments ago. The response includes `retryAfterSeconds`. Wait that long. |
+| `index_rebuild_debounced` | 409 | A rebuild was requested moments ago, or the same commit was re-indexed too recently. The response includes `retryAfterSeconds`. Wait that long. |
 | `provider_disconnected` | 409 | "This repository's provider connection is gone. Reconnect it, or remove it." |
 | `repository_not_found` | 404 | The repository isn't in this workspace. |
 | `subscription_required` | 402 | The workspace plan isn't active. Check **Billing**. |

platform/reviews.mdx

@@ -71,6 +71,15 @@ On **Repositories**, open **Options** for a repository. **PR reviews** turns the
 
 Expand the repository row to see **Unreferenced code (heuristic)**. It is not a switch. The card appears when indexing is on and the graph has nodes. It lists private functions, methods, and classes that nothing in that repository's graph references, and that a text search of the source finds no other use of. A symbol is listed only after it has stayed unreferenced for the number of days the card states, across at least two indexed builds. Code reached through reflection, a string lookup, or another repository can still appear, so check it before you remove it.
 
+## Limits, skips, and the review queue
+
+When Graphify cannot start a review because of a plan limit, the skip is visible on the pull request's **Graphify** check (and as a notice on **Reviews** when the workspace is over its review allowance). Examples:
+
+- Monthly or daily review limit reached — the check says reviews resume at the next UTC reset, and links to billing.
+- Usage limit reached — same idea for the workspace usage cap.
+
+When the workspace already has its maximum number of reviews running, a new review **waits in line** instead of being dropped. The check shows **Queued** with how many reviews are already running. If it does not start within the queue age limit, it is dropped; comment `@graphify review` to retry. Concurrent review limits by plan are on [Plans and pricing](/platform/support/pricing#build-concurrency).
+
 ## Missing or outdated results
 
 Check the selected repository and commit, the settings above, and any plan-limit or access message. A result for an older commit describes that earlier revision. [Repositories and builds](/platform/repositories) explains where to check indexing and repository controls.