Release v2.4.0: merge v2/main into main

.claude/skills/client-smoke/SKILL.md

@@ -154,8 +154,8 @@ server is listening and exit 4. The wait is bounded and checks that this
 server is still alive, so one that fails to bind (the build is missing, the
 port was taken in between) ends the run instead of hanging it. The subshell's `EXIT` trap stops the server by pid even when the CLI call
 fails; a listener left on the port makes the next run talk to the old build.
-By hand in two terminals, the equivalent is waiting for the `listening on
-port` line and stopping the server with Ctrl-C.
+By hand in two terminals, the equivalent is waiting for the listening line
+(`… listening on 127.0.0.1:3917`) and stopping the server with Ctrl-C.
 
 A change to a tool, resource or prompt of `everything` is checked over stdio
 and Streamable HTTP. Check HTTP+SSE as well when the change touches transport

.claude/skills/local-dev/SKILL.md

@@ -71,12 +71,13 @@ PORT=3917 node src/everything/dist/index.js streamableHttp
 ```
 
 Both HTTP transports listen on `PORT`, default `3001`, so they cannot run side
-by side without setting it. Streamable HTTP serves POST, GET and DELETE on
+by side without setting it. They bind `HOST`, default `127.0.0.1` (loopback
+only); `HOST=0.0.0.0` widens it to every interface. Streamable HTTP serves POST, GET and DELETE on
 `/mcp`. HTTP+SSE serves `GET /sse` and `POST /message`; it is deprecated, kept
 working, and never the transport to recommend. The two log to different
 streams: HTTP+SSE writes everything to stderr, while Streamable HTTP writes its
-request and session messages to stdout and its `listening on port` line and
-errors to stderr.
+request and session messages to stdout and its listening line (which names
+the bound `host:port`) and errors to stderr.
 
 ## Run the local package the way a user would
 

.claude/skills/pre-push-gate/SKILL.md

@@ -275,25 +275,35 @@ of the server's stderr. Re-run a subset with
 
 ### `interface-diff`
 
-The last stage diffs the `everything` server's MCP interface (capabilities,
-tools, prompts, resources, resource templates) in this checkout's build
-against the same server built from the merge-base with `origin/v2/main`, and
-prints the report. **A changed interface does not fail it**: the report is
+The last stage diffs the MCP interface (capabilities, tools, prompts,
+resources, resource templates) of each server the change touches, in this
+checkout's build, against the same server built from the merge-base with
+`origin/v2/main`, and prints one report per server. Each report says why that
+server was selected; a change that touches no server prints
+`no server changed` and passes. What selects a server is in
+[`docs/quality-gate.md`](../../../docs/quality-gate.md). **A changed interface does not fail it**: the report is
 what the PR's sticky comment will show, so read it, and if a change is not
 one you meant, that is the finding. It fails only when the diff cannot run,
 with `❌ The interface diff could not run` and the reason:
 
 - **"origin/v2/main is not available"**: `git fetch origin v2/main`.
-- **"src/everything/dist/index.js does not exist"**: you ran it on its own
-  before building: `npm run build -w src/everything`.
-- **An `npm ci` or `npm run build` failure**: the _base_ did not install or
-  build. Offline with a cold npm cache is the usual cause; otherwise name a
+- **"src/<server>/dist/index.js does not exist"**: you ran it on its own
+  before building: `npm run build -w src/<server>`.
+- **"src/<server>/.venv does not exist"**: a Python server was not synced:
+  `cd src/<server> && uv sync --frozen --all-extras --dev` (the gate's
+  `validate:py` does it).
+- **"does not exist at the base"**: the server is new on this branch, so
+  there is no base to diff it against.
+- **An `npm ci`, `npm run build` or `uv sync` failure**: the _base_ did not
+  install or build. Offline with a cold npm cache is the usual cause; otherwise name a
   base that builds with `npm run interface-diff -- --base <ref>`.
 - **"Base server probe failed" / "Target probe failed"**: a server did not
   answer the probe. A target failure is this checkout's server and is the
   real defect; the smoke stage before it usually fails first.
 
-Re-run it on its own with `npm run interface-diff` (about ten seconds). What
+Re-run it on its own with `npm run interface-diff` (about ten seconds for
+every server), `-- --server <name>` for one, or `-- --list` to see what it
+would select and why. What
 it compares against in CI, and why it is a script rather than an action, is
 in [`docs/quality-gate.md`](../../../docs/quality-gate.md) and the header of
 `scripts/interface-diff.mjs`.

.claude/skills/release/SKILL.md

@@ -206,10 +206,10 @@ Then, on the PR:
    ```
 2. **Wait for its CI to pass.** The workflow token's push starts no workflow,
    so the Version Packages workflow dispatches the TypeScript, Python, DCO and
-   Everything diff workflows on `changeset-release/v2/main` after each update.
+   MCP interface diff workflows on `changeset-release/v2/main` after each update.
    A PR does not list dispatched checks, so the result shows as four commit
    statuses: `TypeScript (dispatched)`, `Python (dispatched)`,
-   `DCO (dispatched)` and `Everything diff (dispatched)`. The PR may also
+   `DCO (dispatched)` and `Interface diff (dispatched)`. The PR may also
    list `DCO signoff` and the diff as pending or failed with no jobs: GitHub
    holds the token's `pull_request` runs (#5173), so read the statuses
    instead. Closing and reopening the PR does not start the CI workflows
@@ -255,8 +255,8 @@ gh workflow run prepare-python-release.yml --repo modelcontextprotocol/servers \
 
 It opens a PR that starts with `Closes #N`, on a branch named
 `v2/chore/<N>-python-calver-<date>`, labeled `v2`, and dispatches the
-TypeScript, Python and DCO workflows on that branch, as the Version Packages
-workflow does (not the Everything diff, whose paths it never touches).
+TypeScript, Python, DCO and MCP interface diff workflows on that branch, as
+the Version Packages workflow does.
 No PR means no Python server has a shipped change since its last stamp.
 
 Then, on the PR:
@@ -272,7 +272,7 @@ Then, on the PR:
      --json number,headRefName,url \
      | jq --arg p "v2/chore/$N-python-calver-" '.[] | select(.headRefName | startswith($p))'
    ```
-2. **Wait for its three `(dispatched)` statuses to pass**, check that each
+2. **Wait for its four `(dispatched)` statuses to pass**, check that each
    stamped package really changed, and a maintainer merges it.
 
 ⚠️ GitHub only dispatches a workflow that exists on the default branch. Until