diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index 53045564..5e693cae 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -37,6 +37,30 @@ see [What makes a good issue or prompt submission](#what-makes-a-good-issue-or-p
 below. That's the whole process: you describe the intent, we handle the design
 and implementation.
 
+### Which version, board, and label?
+
+The Inspector is maintained across three versions, each with its own base
+branch, project board, and version label. File your issue against the version
+your report or request targets:
+
+| Version | Base branch | Project board                                                          | Label  |
+| ------- | ----------- | ---------------------------------------------------------------------- | ------ |
+| v1      | `main`      | [v1 board](https://github.com/orgs/modelcontextprotocol/projects/11)   | `v1`   |
+| v1.5    | `v1.5/main` | [v1.5 board](https://github.com/orgs/modelcontextprotocol/projects/39) | `v1.5` |
+| v2      | `v2/main`   | [v2 board](https://github.com/orgs/modelcontextprotocol/projects/28)   | `v2`   |
+
+- **v1** (`main`) is the legacy Inspector — it takes bug fixes and minor
+  improvements only.
+- **v1.5** (`v1.5/main`) is the intermediate version and is **frozen**: it
+  takes no new work and is kept only as a reference point.
+- **v2** (`v2/main`) is where all current work happens — when in doubt, target
+  v2.
+
+**Label by version.** Every issue (and the PRs maintainers open for it) must
+carry the label matching the target board / branch — `v1` for `main`, `v1.5`
+for `v1.5/main`, and `v2` for `v2/main`. This mirrors the "Label by version"
+convention documented in [`AGENTS.md`](./AGENTS.md).
+
 ## If you've already fixed it locally
 
 Please don't send a diff or open a pull request. Instead, open an issue that