AGENTS.md: documentation-drift sweep as explicit pre-commit step

Companion to the same addition in the cloud-init and ansible repos.
Caught real drift in those repos in a recent session only because
the user explicitly asked. Codify the sweep with concrete, repo-
specific drift hotspots rather than a vague 'watch for drift' rule
that gets ignored.

Each AGENTS.md addition lists the doc files most likely to fall
behind code changes here, plus a quick-triage one-liner using
'git diff --name-only HEAD | xargs grep -l ...' so the rule is
actionable not aspirational.

AGENTS.md

@@ -23,7 +23,7 @@ extensions/
   notify.ts               # Native terminal notification when agent finishes
   ext-toggle.ts           # /ext slash command — list & toggle extensions at runtime
   todo.ts                 # `todo` tool for the agent + /todos for the user (copy of upstream example)
-  mcp-loader.ts           # Generic MCP server loader — reads `mcp` block from settings.json
+  mcp-loader.ts           # Generic MCP server loader + /mcp slash command
 install.sh                # Idempotent installer — symlinks extensions/ into ~/.pi/agent/extensions/
 package.json              # pi package manifest — enables `pi install /path` as an alternative
 README.md                 # User-facing docs.
@@ -33,6 +33,8 @@ LICENSE                   # MIT.
 
 ## Conventions
 
+- **Extension imports are coupled to the running pi version.** Extensions are loaded by jiti at runtime; their `import { ... } from "@earendil-works/pi-*"` statements resolve against whatever node_modules the running `pi` binary has bundled. **When extension imports change package names** (e.g. the 2026-05-09 rename from `@mariozechner/pi-*` to `@earendil-works/pi-*`), the host pi MUST be upgraded to the matching version *before or at the same time as* the import-rename push, otherwise users on the older pi see `Cannot find module '@earendil-works/...'` at extension load. Container path: bump `PI_VERSION` build-arg in opencode-devbox. Host path: `npm install -g @earendil-works/pi-coding-agent` (and `brew uninstall pi-coding-agent` if previously installed via brew at the old name). `bun build --external '*'` does NOT catch this regression — it only validates the bundle shape, not module resolution against the runtime pi's deps. Real test: run `pi --version` on the target system after the rename.
+
 - **One `.ts` file per extension**, flat under `extensions/`. If an extension
   grows multiple files, use a subdirectory with an `index.ts` entry point —
   pi's auto-discovery handles both shapes.
@@ -73,8 +75,8 @@ untouched.
 1. **Drop a `.ts` file into `extensions/`.** No other config needed —
    `install.sh` discovers all `.ts` files automatically.
 2. **Export a default factory function** `(pi: ExtensionAPI) => void`.
-   See the [pi extensions docs](https://github.com/mariozechner/pi-coding-agent/blob/main/docs/extensions.md)
+   See the [pi extensions docs](https://github.com/earendil-works/pi/blob/main/docs/extensions.md)
-   and [built-in examples](https://github.com/mariozechner/pi-coding-agent/tree/main/examples/extensions).
+   and [built-in examples](https://github.com/earendil-works/pi/tree/main/examples/extensions).
 3. **Register any CLI flags** via `pi.registerFlag()` so they appear in
    `pi --help`.
 4. **Keep the extension inert without its flag** (or equivalent trigger). Don't
@@ -242,20 +244,22 @@ upstream updates but gain reproducibility.
 **Refresh from upstream when needed:**
 
 ```bash
-cp /opt/homebrew/Cellar/pi-coding-agent/*/libexec/lib/node_modules/@mariozechner/pi-coding-agent/examples/extensions/todo.ts \
+cp /opt/homebrew/Cellar/pi-coding-agent/*/libexec/lib/node_modules/@earendil-works/pi-coding-agent/examples/extensions/todo.ts \
    ~/src/src_local/pi-extensions/extensions/todo.ts
 # review diff, then commit
 ```
 
 ### `mcp-loader.ts`
 
-Generic MCP stdio client — reads an `mcp` block from `~/.pi/agent/settings.json`
+Generic MCP client — reads an `mcp` block from `~/.pi/agent/settings.json`
-and connects to each declared server, exposing the tools as namespaced pi tools.
+and connects to each declared server (stdio subprocess or streamable-HTTP
+endpoint), exposing the tools as namespaced pi tools.
 
 **Why this exists:** pi has no built-in MCP loader (unlike opencode and Claude
 Desktop). Adding each new MCP server as a hand-rolled extension (the way
 `mempalace.ts` does it) doesn't scale past 2-3 servers. This loader is the
-config-driven generalization — one extension, any number of servers.
+config-driven generalization — one extension, any number of servers, two
+transports.
 
 **Key design decisions:**
 
@@ -265,42 +269,72 @@ config-driven generalization — one extension, any number of servers.
   multiple servers expose tools with the same short name. Tools that already
   start with `<servername>_` (the convention some servers like mempalace
   follow internally) skip the prefix to avoid double-prefixing.
+- **Tool names are sanitized to `^[A-Za-z][A-Za-z0-9_]{0,63}$`** before
+  registering with pi. This is the strictest regex we have to satisfy:
+  Anthropic's Messages API allows hyphens, but AWS Bedrock's Anthropic shim
+  rejects them outright — a single hyphenated tool name causes the whole
+  turn to 4xx silently, manifesting as "no output at all" once the offending
+  server is enabled. context7 surfaces this because its tools are named
+  `resolve-library-id` and `query-docs`. We replace any non-`[A-Za-z0-9_]`
+  char with `_`, prepend `t_` if the result doesn't start with a letter, and
+  truncate to 64 chars. The original MCP-side name is kept in the closure
+  used by `client.callTool`, so the sanitization is purely pi-facing.
 - **Fail-soft per server.** A server that won't start (binary missing, init
-  handshake fails) logs one stderr line and is skipped. Other servers
+  handshake fails, remote 4xx/5xx) logs one stderr line and is skipped.
-  continue. Pi keeps working.
+  Other servers continue. Pi keeps working.
-- **Stdio transport only in v1.** Remote/streamable-HTTP servers are
+- **Two transports behind one interface.** `IMcpClient` (`start`, `tools`,
-  detected and skipped with a warning. Adding remote support is the
+  `callTool`, `stop`) is implemented by `StdioMcpClient` (subprocess +
-  obvious v2 (context7 is the prime motivator). Avoided in v1 because
+  newline-delimited JSON-RPC) and `RemoteMcpClient` (HTTP POST + JSON or
-  streamable-HTTP needs SSE parsing, session management, and reconnect
+  SSE response). The extension entry dispatches on `cfg.type` and the
-  logic that triples the implementation size.
+  rest of the code is transport-agnostic.
 - **Does not replace `mempalace.ts`.** The mempalace bridge has bespoke
   agent-identity injection from `$MEMPALACE_AGENT_NAME` that's worth
   preserving. Loader and bridge coexist. Listing `mempalace` in the `mcp`
   block would produce duplicate tool registrations — don't.
-- **No reconnect on subprocess death.** If a server's subprocess crashes
+- **No stdio reconnect on death.** If a stdio subprocess crashes
   mid-session, its tools become permanently unavailable until pi `/reload`s.
-  Same limitation as the mempalace bridge today; not worth complicating v1.
+  Same limitation as the mempalace bridge today.
+- **Remote sessions self-heal on 404.** Per spec 2025-11-25 §2.2, a server
+  that has terminated a session MUST respond with HTTP 404 to requests
+  carrying the stale `Mcp-Session-Id`. `RemoteMcpClient` catches this
+  condition (404 + sessionAtStart was non-null), drops the id, runs a fresh
+  `initialize` + `notifications/initialized`, and retries the original
+  request once. Persistent 404s after refresh surface as errors.
 
 **API used:**
 
 - `pi.registerTool({ name, label, description, parameters, execute })` for
   each MCP tool exposed by each connected server.
-- `pi.on("session_shutdown", ...)` to SIGTERM all subprocesses cleanly.
+- `pi.on("session_shutdown", ...)` to SIGTERM stdio subprocesses and DELETE
+  remote sessions cleanly.
 - `Type.Unsafe<...>(inputSchema)` from typebox to pass the MCP server's
   JSON schema through to pi without conversion (TypeBox schemas are
   plain JSON Schema at runtime).
 
-**Internal MCP client:**
+**Internal MCP clients:**
 
 - `class StdioMcpClient` — spawn subprocess, write newline-delimited
   JSON-RPC, parse newline-delimited responses, match by request `id`.
-- Sends `initialize` handshake with `protocolVersion: 2024-11-05`, then
+  Stderr drained silently unless `PI_MCP_LOADER_DEBUG=1`.
-  `notifications/initialized`, then `tools/list` to discover tools.
+- `class RemoteMcpClient` — streamable-HTTP per MCP spec 2025-03-26.
-- Stderr drained silently unless `PI_MCP_LOADER_DEBUG=1`.
+  POST JSON-RPC body to a single URL with `Accept: application/json,
+  text/event-stream`. Server replies either with one JSON response or an
+  SSE stream containing `event: message` / `data: <json>` blocks; we
+  consume the stream until the response with our `id` arrives, then
+  cancel the reader. Optional `Mcp-Session-Id` header is captured on
+  initialize and round-tripped on every subsequent request, then DELETEd
+  on stop. Per-server `headers` config (e.g. `Authorization`) is merged
+  into every request. No GET-stream subscription — server-initiated
+  notifications are not consumed.
+- Both share `interface IMcpClient { serverName, tools, start, callTool, stop }`.
+  Both send `initialize` handshake with `protocolVersion: MCP_PROTOCOL_VERSION`
+  (currently `2025-11-25`, per the constant at the top of the file),
+  then `notifications/initialized`, then `tools/list` to discover tools.
 
-**Future v2 extensions:**
+**Future extensions:**
 
-- Streamable-HTTP transport for remote servers (context7).
+- OAuth flow for remote servers that require it (today: pre-issued bearer
+  tokens via `headers` only).
 - Per-tool enable/disable in settings.json (e.g.
   `"mcp.searxng.tools": ["web_search"]` to expose only a subset).
 - Reconnect-on-crash with exponential backoff.
@@ -366,3 +400,14 @@ pi --ssh user@host --ssh-ask-pass
   — same pattern for agent skills rather than extensions.
 - [`opencode-devbox`](https://gitea.jordbo.se/joakimp/opencode-devbox)
   — Docker containers; composes toolkits via independent install.sh calls.
+
+## Documentation drift sweep
+
+Before committing any non-trivial change, check that prose still matches code. Drift hotspots in this repo:
+
+- `README.md` — the per-extension feature/usage descriptions, the install instructions, the dependency list. When an extension's flags or behaviour change, the README block for that extension is the first thing to update.
+- `AGENTS.md` (this file) — the `Extension-specific notes` section is large and easy to leave stale. Each extension has its own subsection; if you change a flag, hook, or default, update the subsection here as well as the README.
+- Extension files themselves — the `// description:` comment header pi parses for the extension list view must stay accurate.
+- `install.sh` — `--only` / `--skip` defaults, the list of artifacts it knows about, and the symlink targets. If you add a new extension file, the installer's auto-discovery picks it up; if you add a new artifact type that needs special handling, the script must be updated and the README block describing what `install.sh does` along with it.
+
+Quick triage: `git diff --name-only HEAD | xargs -I{} grep -l 'thing-you-changed' README.md AGENTS.md install.sh`. For an extension rename, also grep for the old name across the whole repo.

README.md

@@ -1,6 +1,6 @@
 # pi-extensions
 
-Custom and modified extensions for the [pi coding-agent](https://github.com/mariozechner/pi-coding-agent).
+Custom and modified extensions for the [pi coding-agent](https://github.com/earendil-works/pi).
 
 This repo is the single source of truth for extensions that aren't suitable for general publishing — personal workflow tweaks, modified versions of built-in examples, and extensions written for specific infrastructure. Symlinked into `~/.pi/agent/extensions/` so pi loads them automatically.
 
@@ -205,7 +205,7 @@ This is a verbatim copy of the upstream `examples/extensions/todo.ts` shipped wi
 
 ### `mcp-loader.ts`
 
-Generic MCP server loader. Reads an `mcp` block from `~/.pi/agent/settings.json` (same shape as opencode and Claude Desktop) and connects to each declared server, exposing all of their tools to pi as native tools — namespaced as `<server-name>_<tool-name>` to avoid collisions.
+Generic MCP server loader. Reads an `mcp` block from `~/.pi/agent/settings.json` (same shape as opencode and Claude Desktop) and connects to each declared server, exposing all of their tools to pi as native tools — namespaced as `<server-name>_<tool-name>` to avoid collisions, with non-`[A-Za-z0-9_]` characters replaced by `_` so the names pass the strictest provider tool-name regex (e.g. AWS Bedrock).
 
 **Settings.json shape:**
 
@@ -239,18 +239,34 @@ Generic MCP server loader. Reads an `mcp` block from `~/.pi/agent/settings.json`
 | `type` | `"local"` (stdio subprocess) or `"remote"` (streamable-http). Default `"local"`. |
 | `command` | Argv array. First element is the executable, rest are args. Local servers only. |
 | `url` | Remote MCP endpoint URL. Remote servers only. |
+| `headers` | Optional object of HTTP headers (e.g. `Authorization`, `X-API-Key`) sent with every request. Remote servers only. |
 | `enabled` | Default `true`. Set `false` to disable a server without removing the entry. |
 | `env` | Optional object of env vars injected into the subprocess. Inherits parent env first, then overlays these keys. Local servers only. |
 
-**Limitations (v1):**
+**Transports:**
 
-- **Stdio only.** Remote/streamable-HTTP transport is detected and skipped with a warning. Server like `context7` configured as `"type": "remote"` will not load until v2.
+- `local` — stdio JSON-RPC subprocess (mcp-searxng, gitea-mcp, mcp-server-time…).
-- **No reconnect** if a subprocess dies mid-session — those tools become unavailable until `/reload` (same as `mempalace.ts`).
+- `remote` — streamable-HTTP per MCP spec 2025-03-26: POST JSON-RPC, server replies either `application/json` or `text/event-stream`. Optional `Mcp-Session-Id` round-trip if the server issues one. No GET subscription stream (server-initiated notifications are not consumed).
+
+**Limitations:**
+
+- **No stdio reconnect** if a subprocess dies mid-session — those tools become unavailable until `/reload` (same as `mempalace.ts`).
+- **Remote sessions self-heal on 404.** If a streamable-HTTP server forgets our session id (e.g. server restart), the client transparently re-initializes and retries the request once.
+- **No OAuth flow.** Remote servers requiring OAuth must be accessed with a pre-issued bearer token via `headers`.
 - **Coexists with `mempalace.ts`** but does not replace it. The mempalace bridge has bespoke handling (agent identity injection) that's worth keeping. Don't list `mempalace` in the `mcp` block too — you'd get duplicate tool registrations.
 
 **Debug:** set `PI_MCP_LOADER_DEBUG=1` in the environment to surface per-server stderr and connection logs.
 
-Each extension is a TypeScript module loaded by [jiti](https://github.com/unjs/jiti) — no compilation step. See the [pi extensions docs](https://github.com/mariozechner/pi-coding-agent/blob/main/docs/extensions.md) and the [built-in examples](https://github.com/mariozechner/pi-coding-agent/tree/main/examples/extensions) for the API surface.
+**Slash command:** `/mcp` opens a multi-toggle overlay listing every server in the `mcp` block with its runtime status:
+
+- `running · N tools` — connected, tools registered
+- `failed: <message>` — start handshake threw
+- `disabled in settings` — `enabled: false`
+- `invalid: <message>` — malformed config (read-only row)
+
+UX matches `/ext`: **space** stages a toggle, **enter** writes back to `settings.json` and reloads pi, **esc** cancels. Toggling re-enables a previously-disabled server by removing the explicit `enabled` key (the default is `true`).
+
+Each extension is a TypeScript module loaded by [jiti](https://github.com/unjs/jiti) — no compilation step. See the [pi extensions docs](https://github.com/earendil-works/pi/blob/main/docs/extensions.md) and the [built-in examples](https://github.com/earendil-works/pi/tree/main/examples/extensions) for the API surface.
 
 ---
 

extensions/confirm-destructive.ts

@@ -10,7 +10,7 @@
  *    /fork so you don't accidentally throw away work.
  */
 
-import type { ExtensionAPI, SessionBeforeSwitchEvent, SessionMessageEntry } from "@mariozechner/pi-coding-agent";
+import type { ExtensionAPI, SessionBeforeSwitchEvent, SessionMessageEntry } from "@earendil-works/pi-coding-agent";
 
 // ── Dangerous bash patterns ───────────────────────────────────────────────────
 

extensions/ext-toggle.ts

@@ -30,14 +30,14 @@ import * as os from "node:os";
 import {
   type ExtensionAPI,
   getSettingsListTheme,
-} from "@mariozechner/pi-coding-agent";
+} from "@earendil-works/pi-coding-agent";
 import {
   Container,
   Key,
   matchesKey,
   type SettingItem,
   SettingsList,
-} from "@mariozechner/pi-tui";
+} from "@earendil-works/pi-tui";
 
 const EXT_DIR = path.join(os.homedir(), ".pi", "agent", "extensions");
 
@@ -58,6 +58,18 @@ const DISABLE_GUARDS: Record<string, () => string | null> = {
     if (!hasSshFlag) return null;
     return "Active --ssh session — disabling would silently revert read/write/edit/bash to local. Exit pi and relaunch without --ssh.";
   },
+  // ext-toggle owns the /ext slash command. Disabling it removes the
+  // only TUI surface for re-enabling itself: pi auto-discovers `*.ts`
+  // only, so once renamed to `.ts.off` the file is invisible to pi and
+  // the next /reload silently drops the command. The disabled state
+  // also persists — in containerized setups (opencode-devbox) the
+  // ~/.pi volume keeps the `.ts.off` rename across container recreate,
+  // so even nuking the container doesn't recover the surface. Recovery
+  // path is manual: shell into the container (or open a host shell),
+  // run `mv ~/.pi/agent/extensions/ext-toggle.ts.off \
+  // ~/.pi/agent/extensions/ext-toggle.ts`, then /reload.
+  "ext-toggle": () =>
+    "Disabling ext-toggle would remove the /ext command itself — only manual `mv ~/.pi/agent/extensions/ext-toggle.ts.off ~/.pi/agent/extensions/ext-toggle.ts` recovers it. Refusing.",
 };
 
 // ── Filesystem helpers ────────────────────────────────────────────────────────

extensions/git-checkpoint.ts

@@ -11,7 +11,7 @@
  * Status bar shows the number of checkpoints saved in the current session.
  */
 
-import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
 
 export default function (pi: ExtensionAPI) {
   // entryId → stash ref (e.g. "refs/stash" or a full sha)

extensions/mcp-loader.ts

@@ -22,7 +22,8 @@
  *     },
  *     "context7": {
  *       "type": "remote",
- *       "url": "https://mcp.context7.com/mcp"
+ *       "url": "https://mcp.context7.com/mcp",
+ *       "headers": { "Authorization": "Bearer …" }
  *     }
  *   }
  * }
@@ -32,11 +33,13 @@
  *   command  argv array — first element is the executable, rest are args.
  *            For local servers only.
  *   url      remote MCP endpoint URL. For remote servers only.
+ *   headers  optional object of HTTP headers to send with every request to
+ *            a remote server (e.g. Authorization, X-API-Key). Remote only.
  *   enabled  default true. Set false to disable a server without
  *            removing it from settings.json.
  *   env      optional object of environment variables to inject into
  *            the spawned subprocess. Inherits parent env first, then
- *            overlays these keys.
+ *            overlays these keys. Local only.
  *
  * Tool naming
  *
@@ -47,22 +50,35 @@
  *
  * Lifecycle
  *
- *   • Servers are spawned at extension load time (pi startup or /reload).
+ *   • Servers are connected at extension load time (pi startup or /reload).
  *   • Each server's `tools/list` is awaited before pi finishes registering.
- *   • Subprocess stderr is silenced unless PI_MCP_LOADER_DEBUG=1.
+ *   • Local subprocess stderr is silenced unless PI_MCP_LOADER_DEBUG=1.
- *   • Subprocesses receive SIGTERM at session_shutdown.
+ *   • Local subprocesses receive SIGTERM at session_shutdown; remote
- *   • A server that fails to start (binary missing, init handshake error)
+ *     servers receive an MCP DELETE if a session id was issued.
- *     logs a single line to stderr and is skipped. Other servers continue.
+ *   • A server that fails to start (binary missing, init handshake error,
- *     Pi keeps working without that server's tools.
+ *     remote 4xx/5xx) logs a single line to stderr and is skipped. Other
+ *     servers continue. Pi keeps working without that server's tools.
  *
- * Limitations (v1)
+ * Transports
  *
- *   • Only local/stdio transport is implemented. Remote (streamable-http,
+ *   local  — stdio JSON-RPC subprocess (mcp-searxng, gitea-mcp, …).
- *     SSE) servers are detected and skipped with a warning. v2 will add
+ *   remote — streamable-HTTP per MCP spec 2025-03-26: POST JSON-RPC, server
- *     remote support — context7 is the prime motivator.
+ *            replies either application/json or text/event-stream. Optional
- *   • No reconnect: if a subprocess dies mid-session, its tools become
+ *            Mcp-Session-Id header round-tripped if the server issues one.
- *     unavailable until pi is reloaded. The mempalace.ts extension has
+ *            No GET-stream subscription (we don't consume server-initiated
- *     the same limitation today.
+ *            notifications).
+ *
+ * Limitations
+ *
+ *   • No stdio reconnect: if a stdio subprocess dies mid-session, its tools
+ *     become unavailable until pi is reloaded. The mempalace.ts extension
+ *     has the same limitation today.
+ *   • Remote sessions self-heal on 404: if a streamable-HTTP server
+ *     forgets our session id (e.g. server restart), the next request gets
+ *     HTTP 404; the client transparently re-initializes and retries the
+ *     request once. Persistent 404s after refresh surface as errors.
+ *   • No OAuth flow: remote servers requiring OAuth must be accessed with
+ *     a pre-issued bearer token via `headers`.
  *
  * Coexistence with mempalace.ts
  *
@@ -72,13 +88,30 @@
  *   bespoke extension in place. If you also list mempalace under the `mcp`
  *   block in settings.json the loader will register a parallel set of
  *   tools, which is harmless but redundant. Don't.
+ *
+ * Slash command
+ *
+ *   `/mcp` lists configured MCP servers with their runtime status
+ *   (running / failed / disabled / invalid) and lets
+ *   you toggle the `enabled` flag in settings.json. Same UX as `/ext`:
+ *   space stages, enter applies + reloads, esc cancels.
  */
 
 import { type ChildProcessWithoutNullStreams, spawn } from "node:child_process";
 import * as fs from "node:fs";
 import * as os from "node:os";
 import * as path from "node:path";
-import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import {
+  type ExtensionAPI,
+  getSettingsListTheme,
+} from "@earendil-works/pi-coding-agent";
+import {
+  Container,
+  Key,
+  matchesKey,
+  type SettingItem,
+  SettingsList,
+} from "@earendil-works/pi-tui";
 import { Type } from "typebox";
 
 // ── MCP types ────────────────────────────────────────────────────────────────
@@ -99,6 +132,7 @@ type LocalServerConfig = {
 type RemoteServerConfig = {
   type: "remote";
   url: string;
+  headers?: Record<string, string>;
   enabled?: boolean;
 };
 
@@ -107,6 +141,13 @@ type ServerConfig = LocalServerConfig | RemoteServerConfig;
 const SETTINGS_PATH = path.join(os.homedir(), ".pi", "agent", "settings.json");
 const DEBUG = process.env.PI_MCP_LOADER_DEBUG === "1";
 
+// MCP protocol version we advertise. Servers we've tested:
+//   - searxng (mcp-searxng) accepts both 2024-11-05 and 2025-11-25
+//   - context7 accepts both
+//   - mempalace bridge: not touched by this loader
+// Bump as the spec evolves; both stdio and remote clients use this.
+const MCP_PROTOCOL_VERSION = "2025-11-25";
+
 function dlog(msg: string) {
   if (DEBUG) process.stderr.write(`[mcp-loader] ${msg}\n`);
 }
@@ -145,21 +186,35 @@ function readMcpServers(): Record<string, ServerConfig> {
 
 // ── Stdio MCP client ─────────────────────────────────────────────────────────
 
-class StdioMcpClient {
+interface IMcpClient {
+  readonly serverName: string;
+  tools: McpTool[];
+  start(): Promise<void>;
+  callTool(name: string, args: Record<string, unknown>): Promise<any>;
+  stop(): void | Promise<void>;
+}
+
+class StdioMcpClient implements IMcpClient {
   private proc: ChildProcessWithoutNullStreams | null = null;
   private nextId = 1;
   private pending = new Map<number, { resolve: (v: any) => void; reject: (e: Error) => void }>();
   private stdoutBuf = "";
-  private serverName: string;
+  public readonly serverName: string;
+  private command: string;
+  private args: string[];
+  private env: Record<string, string> | undefined;
   public tools: McpTool[] = [];
 
-  constructor(serverName: string) {
+  constructor(serverName: string, command: string, args: string[], env?: Record<string, string>) {
     this.serverName = serverName;
+    this.command = command;
+    this.args = args;
+    this.env = env;
   }
 
-  async start(command: string, args: string[], env?: Record<string, string>): Promise<void> {
+  async start(): Promise<void> {
-    const childEnv = { ...process.env, ...(env ?? {}) };
+    const childEnv = { ...process.env, ...(this.env ?? {}) };
-    this.proc = spawn(command, args, { stdio: ["pipe", "pipe", "pipe"], env: childEnv });
+    this.proc = spawn(this.command, this.args, { stdio: ["pipe", "pipe", "pipe"], env: childEnv });
 
     this.proc.on("error", (err) => this.failAll(err));
     this.proc.on("exit", (code, signal) => {
@@ -180,9 +235,9 @@ class StdioMcpClient {
 
     // MCP initialize handshake
     await this.request("initialize", {
-      protocolVersion: "2024-11-05",
+      protocolVersion: MCP_PROTOCOL_VERSION,
       capabilities: {},
-      clientInfo: { name: "pi-mcp-loader", version: "0.1.0" },
+      clientInfo: { name: "pi-mcp-loader", version: "0.2.0" },
     });
     this.notify("notifications/initialized", {});
 
@@ -249,6 +304,195 @@ class StdioMcpClient {
   }
 }
 
+// ── Streamable-HTTP MCP client (remote) ──────────────────────────────────────
+//
+// Per MCP spec 2025-03-26: a single endpoint URL accepts POST with a
+// JSON-RPC body. The server responds either with application/json (a
+// single response) or text/event-stream (an SSE stream containing the
+// response, possibly preceded by notifications, terminated by stream
+// close). We do NOT open a separate GET subscription stream — we don't
+// consume server-initiated notifications today.
+//
+// Session id: if the server returns an Mcp-Session-Id header on
+// initialize, we round-trip it on every subsequent request and DELETE
+// it on stop().
+
+class RemoteMcpClient implements IMcpClient {
+  public readonly serverName: string;
+  private url: string;
+  private extraHeaders: Record<string, string>;
+  private sessionId: string | null = null;
+  private nextId = 1;
+  public tools: McpTool[] = [];
+
+  constructor(serverName: string, url: string, headers?: Record<string, string>) {
+    this.serverName = serverName;
+    this.url = url;
+    this.extraHeaders = headers ?? {};
+  }
+
+  async start(): Promise<void> {
+    await this.request("initialize", {
+      protocolVersion: MCP_PROTOCOL_VERSION,
+      capabilities: {},
+      clientInfo: { name: "pi-mcp-loader", version: "0.2.0" },
+    });
+    await this.notify("notifications/initialized", {});
+    const listed = await this.request("tools/list", {});
+    this.tools = (listed?.tools as McpTool[]) ?? [];
+  }
+
+  async callTool(name: string, args: Record<string, unknown>): Promise<any> {
+    return this.request("tools/call", { name, arguments: args });
+  }
+
+  async stop(): Promise<void> {
+    if (!this.sessionId) return;
+    try {
+      await fetch(this.url, { method: "DELETE", headers: this.buildHeaders() });
+    } catch {}
+  }
+
+  private buildHeaders(): Record<string, string> {
+    const h: Record<string, string> = {
+      "Content-Type": "application/json",
+      Accept: "application/json, text/event-stream",
+      "MCP-Protocol-Version": MCP_PROTOCOL_VERSION,
+      ...this.extraHeaders,
+    };
+    if (this.sessionId) h["Mcp-Session-Id"] = this.sessionId;
+    return h;
+  }
+
+  /**
+   * Re-establish a session after the server returned 404 to a request that
+   * carried our `Mcp-Session-Id`. Per spec 2025-11-25, the client MUST start
+   * a new session by sending a fresh InitializeRequest without a session id.
+   *
+   * Caller must clear `this.sessionId` BEFORE invoking this so the new
+   * initialize POST goes out without the stale id.
+   */
+  private async reinitialize(): Promise<void> {
+    dlog(`${this.serverName}: session lost (404) — reinitializing`);
+    await this.request("initialize", {
+      protocolVersion: MCP_PROTOCOL_VERSION,
+      capabilities: {},
+      clientInfo: { name: "pi-mcp-loader", version: "0.2.0" },
+    }, /*allowReinitOn404=*/ false);
+    await this.notify("notifications/initialized", {});
+  }
+
+  private async request(method: string, params: unknown, allowReinitOn404 = true): Promise<any> {
+    const id = this.nextId++;
+    const body = JSON.stringify({ jsonrpc: "2.0", id, method, params });
+    const sessionAtStart = this.sessionId;
+    let res: Response;
+    try {
+      res = await fetch(this.url, { method: "POST", headers: this.buildHeaders(), body });
+    } catch (err) {
+      throw new Error(`${this.serverName}: fetch failed on ${method}: ${(err as Error).message}`);
+    }
+
+    const sid = res.headers.get("Mcp-Session-Id") ?? res.headers.get("mcp-session-id");
+    if (sid) this.sessionId = sid;
+
+    // 404 + we sent a session id → server forgot us. Drop our id, re-init,
+    // retry once. `allowReinitOn404=false` is passed by the recovery path to
+    // prevent infinite recursion if the server is permanently broken.
+    if (res.status === 404 && sessionAtStart && allowReinitOn404) {
+      try { await res.arrayBuffer(); } catch {}
+      this.sessionId = null;
+      await this.reinitialize();
+      return this.request(method, params, /*allowReinitOn404=*/ false);
+    }
+
+    if (!res.ok) {
+      let detail = "";
+      try { detail = (await res.text()).slice(0, 200); } catch {}
+      throw new Error(`${this.serverName}: HTTP ${res.status} on ${method}${detail ? `: ${detail}` : ""}`);
+    }
+
+    const ct = (res.headers.get("content-type") ?? "").toLowerCase();
+    if (ct.includes("text/event-stream")) {
+      return await this.readSseForResponse(res, id);
+    }
+    if (ct.includes("application/json")) {
+      const json: any = await res.json();
+      if (json.error) throw new Error(json.error.message ?? "MCP error");
+      return json.result;
+    }
+    if (res.status === 202) return undefined;
+    throw new Error(`${this.serverName}: unexpected content-type "${ct}" on ${method}`);
+  }
+
+  private async notify(method: string, params: unknown): Promise<void> {
+    const body = JSON.stringify({ jsonrpc: "2.0", method, params });
+    let res: Response;
+    try {
+      res = await fetch(this.url, { method: "POST", headers: this.buildHeaders(), body });
+    } catch (err) {
+      throw new Error(`${this.serverName}: fetch failed on notify ${method}: ${(err as Error).message}`);
+    }
+    try { await res.arrayBuffer(); } catch {}
+    if (!res.ok && res.status !== 202) {
+      throw new Error(`${this.serverName}: HTTP ${res.status} on notify ${method}`);
+    }
+  }
+
+  private async readSseForResponse(res: Response, expectedId: number): Promise<any> {
+    if (!res.body) throw new Error(`${this.serverName}: SSE response had no body`);
+    const reader = res.body.getReader();
+    const decoder = new TextDecoder();
+    let buf = "";
+    let dataLines: string[] = [];
+
+    const tryDispatch = (): { matched: boolean; result?: any } => {
+      if (dataLines.length === 0) return { matched: false };
+      const data = dataLines.join("\n");
+      dataLines = [];
+      let msg: any;
+      try {
+        msg = JSON.parse(data);
+      } catch {
+        return { matched: false };
+      }
+      if (typeof msg.id === "number" && msg.id === expectedId) {
+        if (msg.error) throw new Error(msg.error.message ?? "MCP error");
+        return { matched: true, result: msg.result };
+      }
+      return { matched: false };
+    };
+
+    try {
+      while (true) {
+        const { done, value } = await reader.read();
+        if (done) break;
+        buf += decoder.decode(value, { stream: true });
+        let nl: number;
+        while ((nl = buf.indexOf("\n")) !== -1) {
+          const rawLine = buf.slice(0, nl);
+          buf = buf.slice(nl + 1);
+          const line = rawLine.endsWith("\r") ? rawLine.slice(0, -1) : rawLine;
+          if (line === "") {
+            const out = tryDispatch();
+            if (out.matched) return out.result;
+          } else if (line.startsWith(":")) {
+            // SSE comment — ignore (often a keepalive)
+          } else if (line.startsWith("data:")) {
+            dataLines.push(line.slice(5).replace(/^ /, ""));
+          }
+          // event:, id:, retry: — ignored; only `data` matters for our use
+        }
+      }
+      const out = tryDispatch();
+      if (out.matched) return out.result;
+    } finally {
+      try { reader.cancel(); } catch {}
+    }
+    throw new Error(`${this.serverName}: SSE stream closed without response for id=${expectedId}`);
+  }
+}
+
 // ── MCP result → pi tool result helpers ──────────────────────────────────────
 
 function extractText(mcpResult: any): string {
@@ -267,52 +511,107 @@ function namespacedToolName(serverName: string, toolName: string): string {
   // Avoid double-prefix: if the MCP server already names its tools
   // `<serverName>_<...>`, leave them alone.
   const prefix = `${serverName}_`;
-  if (toolName.startsWith(prefix)) return toolName;
+  const raw = toolName.startsWith(prefix) ? toolName : `${prefix}${toolName}`;
-  return `${prefix}${toolName}`;
+  // Sanitize for the strictest tool-name regex we have to satisfy.
+  // Anthropic's Messages API allows `^[a-zA-Z0-9_-]{1,64}$` (hyphens OK),
+  // but AWS Bedrock's Anthropic shim rejects names containing `-` outright
+  // — it accepts `^[a-zA-Z][a-zA-Z0-9_]{0,63}$`. Hyphenated MCP tool names
+  // (context7's `resolve-library-id`, `query-docs`) caused entire turns to
+  // 4xx silently on Bedrock, manifesting as no output at all once the
+  // server was enabled. Replace any non-[A-Za-z0-9_] with `_`, then prefix
+  // a leading underscore with `t` if the result starts with a non-letter.
+  // Truncate to 64 to also satisfy Anthropic's length cap.
+  let sanitized = raw.replace(/[^A-Za-z0-9_]/g, "_");
+  if (!/^[A-Za-z]/.test(sanitized)) sanitized = `t_${sanitized}`;
+  if (sanitized.length > 64) sanitized = sanitized.slice(0, 64);
+  return sanitized;
 }
 
+// ── Settings.json writer ─────────────────────────────────────────────────────
+
+/**
+ * Flip the `enabled` flag for a server in settings.json and write back.
+ * Preserves all other keys verbatim by round-tripping through JSON with
+ * 2-space indent (matches the file's existing style).
+ */
+function setServerEnabled(serverName: string, enabled: boolean): void {
+  const raw = fs.readFileSync(SETTINGS_PATH, "utf8");
+  const parsed = JSON.parse(raw);
+  if (!parsed.mcp || !parsed.mcp[serverName]) {
+    throw new Error(`server '${serverName}' not in settings.json`);
+  }
+  if (enabled) {
+    // Default is true — clear the explicit flag if present, keep the file tidy.
+    delete parsed.mcp[serverName].enabled;
+  } else {
+    parsed.mcp[serverName].enabled = false;
+  }
+  fs.writeFileSync(SETTINGS_PATH, `${JSON.stringify(parsed, null, 2)}\n`, "utf8");
+}
+
+// ── Per-server runtime state (for /mcp display) ──────────────────────────────
+
+type ServerRuntimeState =
+  | { kind: "running"; toolCount: number }
+  | { kind: "failed"; message: string }
+  | { kind: "disabled" }
+  | { kind: "invalid"; message: string };
+
 // ── Extension entry ──────────────────────────────────────────────────────────
 
 export default async function mcpLoaderExtension(pi: ExtensionAPI) {
   const servers = readMcpServers();
-  const serverNames = Object.keys(servers);
+  const runtime = new Map<string, ServerRuntimeState>();
-  if (serverNames.length === 0) {
+  const clients: IMcpClient[] = [];
-    dlog("no MCP servers configured — nothing to do");
+
+  // Always register /mcp — even when no servers are configured, so users
+  // discover the surface. Handler reads settings.json fresh on each invoke.
+  registerMcpCommand(pi, runtime);
+
+  if (Object.keys(servers).length === 0) {
+    dlog("no MCP servers configured — nothing to load");
     return;
   }
 
-  const clients: StdioMcpClient[] = [];
-
   for (const [name, cfg] of Object.entries(servers)) {
     if (cfg.enabled === false) {
       dlog(`${name}: disabled in settings.json, skipping`);
+      runtime.set(name, { kind: "disabled" });
       continue;
     }
 
+    let client: IMcpClient;
     if (cfg.type === "remote") {
-      warn(
+      const remote = cfg as RemoteServerConfig;
-        `${name}: remote MCP transport not yet supported by mcp-loader (v1 is stdio-only); skipping`,
+      if (typeof remote.url !== "string" || remote.url.length === 0) {
-      );
+        warn(`${name}: remote server missing \`url\`, skipping`);
+        runtime.set(name, { kind: "invalid", message: "remote server missing url" });
         continue;
       }
-
+      client = new RemoteMcpClient(name, remote.url, remote.headers);
+    } else {
       const local = cfg as LocalServerConfig;
       if (!Array.isArray(local.command) || local.command.length === 0) {
         warn(`${name}: invalid \`command\` (must be non-empty array), skipping`);
+        runtime.set(name, { kind: "invalid", message: "command must be non-empty array" });
         continue;
       }
       const [bin, ...args] = local.command;
+      client = new StdioMcpClient(name, bin, args, local.env);
+    }
 
-    const client = new StdioMcpClient(name);
     try {
-      await client.start(bin, args, local.env);
+      await client.start();
     } catch (err) {
-      warn(`${name}: failed to start — ${(err as Error).message}`);
+      const message = (err as Error).message;
-      client.stop();
+      warn(`${name}: failed to start — ${message}`);
+      runtime.set(name, { kind: "failed", message });
+      try { await client.stop(); } catch {}
       continue;
     }
 
     dlog(`${name}: connected, ${client.tools.length} tools`);
+    runtime.set(name, { kind: "running", toolCount: client.tools.length });
     clients.push(client);
 
     // Register each MCP tool as a pi tool.
@@ -355,8 +654,182 @@ export default async function mcpLoaderExtension(pi: ExtensionAPI) {
     }
   }
 
-  // Tear down subprocesses on session shutdown so reloads don't leak procs.
+  // Tear down clients (stdio subprocesses, remote sessions) on session shutdown.
   pi.on("session_shutdown", async () => {
-    for (const c of clients) c.stop();
+    await Promise.allSettled(clients.map((c) => Promise.resolve(c.stop())));
+  });
+}
+
+// ── /mcp slash command ──────────────────────────────────────────────────────
+
+const VAL_ON = "● enabled";
+const VAL_OFF = "○ disabled";
+const VAL_RO = "[read-only]";
+
+function statusLabel(state: ServerRuntimeState | undefined, configEnabled: boolean): string {
+  if (!state) return configEnabled ? "unknown" : "disabled";
+  switch (state.kind) {
+    case "running":
+      return `running · ${state.toolCount} tool${state.toolCount === 1 ? "" : "s"}`;
+    case "failed":
+      return `failed: ${state.message}`;
+    case "disabled":
+      return "disabled in settings";
+    case "invalid":
+      return `invalid: ${state.message}`;
+  }
+}
+
+function registerMcpCommand(pi: ExtensionAPI, runtime: Map<string, ServerRuntimeState>) {
+  pi.registerCommand("mcp", {
+    description: "List and toggle MCP servers configured in ~/.pi/agent/settings.json",
+    handler: async (_args, ctx) => {
+      const servers = readMcpServers();
+      const names = Object.keys(servers);
+      if (names.length === 0) {
+        ctx.ui.notify(
+          `No MCP servers configured. Add an \`mcp\` block to ${SETTINGS_PATH}.`,
+          "info",
+        );
+        return;
+      }
+
+      // Snapshot config-level enabled state (default true if unset).
+      const configEnabled = new Map<string, boolean>();
+      for (const [n, cfg] of Object.entries(servers)) {
+        configEnabled.set(n, cfg.enabled !== false);
+      }
+
+      // Staged state: name → enabled (initialised from configEnabled).
+      const staged = new Map(configEnabled);
+
+      await ctx.ui.custom<void>((tui, theme, _kb, done) => {
+        let statusText = "";
+
+        const items: SettingItem[] = names.map((n) => {
+          const cfg = servers[n];
+          const cfgEn = configEnabled.get(n) ?? true;
+          const state = runtime.get(n);
+          const isRemote = cfg.type === "remote";
+          const isInvalid = state?.kind === "invalid";
+          const transport = isRemote ? "remote" : "local";
+          const desc = `${transport} · ${statusLabel(state, cfgEn)}`;
+
+          if (isInvalid) {
+            return {
+              id: n,
+              label: n,
+              currentValue: VAL_RO,
+              description: desc,
+            };
+          }
+          return {
+            id: n,
+            label: n,
+            currentValue: cfgEn ? VAL_ON : VAL_OFF,
+            values: [VAL_ON, VAL_OFF],
+            description: desc,
+          };
+        });
+
+        const container = new Container();
+
+        container.addChild({
+          render(_w: number) {
+            return [
+              theme.fg("accent", theme.bold("MCP servers — settings.json `mcp` block")),
+              theme.fg(
+                "muted",
+                "  space: toggle (stage) · enter: apply + reload · esc: cancel",
+              ),
+              "",
+            ];
+          },
+          invalidate() {},
+        });
+
+        const settingsList = new SettingsList(
+          items,
+          Math.min(items.length + 2, 20),
+          getSettingsListTheme(),
+          (id, newValue) => {
+            const isInvalid = runtime.get(id)?.kind === "invalid";
+            if (isInvalid) {
+              settingsList.updateValue(id, VAL_RO);
+              statusText = `⊘ ${id}: invalid config — fix in settings.json`;
+              tui.requestRender();
+              return;
+            }
+            const stagingEnabled = newValue === VAL_ON;
+            staged.set(id, stagingEnabled);
+
+            const drift: string[] = [];
+            for (const n of names) {
+              const s = staged.get(n);
+              const c = configEnabled.get(n);
+              if (s !== undefined && s !== c) drift.push(`${n}→${s ? "on" : "off"}`);
+            }
+            statusText = drift.length ? `pending: ${drift.join(", ")}` : "";
+            tui.requestRender();
+          },
+          () => {
+            done(undefined);
+          },
+        );
+
+        container.addChild(settingsList);
+
+        container.addChild({
+          render(_w: number) {
+            if (!statusText) return [""];
+            const colored = statusText.startsWith("⊘")
+              ? theme.fg("warning", statusText)
+              : theme.fg("muted", statusText);
+            return ["", colored];
+          },
+          invalidate() {},
+        });
+
+        return {
+          render(width: number) {
+            return container.render(width);
+          },
+          invalidate() {
+            container.invalidate();
+          },
+          handleInput(data: string) {
+            if (matchesKey(data, Key.enter)) {
+              const errors: string[] = [];
+              let applied = 0;
+              for (const n of names) {
+                const s = staged.get(n);
+                const c = configEnabled.get(n);
+                if (s === undefined || s === c) continue;
+                try {
+                  setServerEnabled(n, s);
+                  applied++;
+                } catch (err) {
+                  const msg = err instanceof Error ? err.message : String(err);
+                  errors.push(`${n}: ${msg}`);
+                }
+              }
+              done(undefined);
+              if (errors.length) {
+                ctx.ui.notify(`mcp: ${errors.join(" | ")}`, "error");
+              } else if (applied > 0) {
+                ctx.ui.notify(`mcp: applied ${applied} change(s); reloading…`, "info");
+                ctx.reload().catch((err) => {
+                  const msg = err instanceof Error ? err.message : String(err);
+                  ctx.ui.notify(`reload failed: ${msg}`, "error");
+                });
+              }
+              return;
+            }
+            settingsList.handleInput?.(data);
+            tui.requestRender();
+          },
+        };
+      });
+    },
   });
 }

extensions/notify.ts

@@ -13,7 +13,7 @@
  *   otherwise       → OSC 777  (iTerm2, WezTerm, Ghostty, rxvt-unicode)
  */
 
-import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
 
 // ── Notification backends ─────────────────────────────────────────────────────
 

extensions/ssh-controlmaster.ts

@@ -31,7 +31,7 @@ import { spawn } from "node:child_process";
 import { writeFile, unlink } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
-import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
 import {
   type BashOperations,
   createBashTool,
@@ -41,7 +41,7 @@ import {
   type EditOperations,
   type ReadOperations,
   type WriteOperations,
-} from "@mariozechner/pi-coding-agent";
+} from "@earendil-works/pi-coding-agent";
 
 // ── Types ────────────────────────────────────────────────────────────────────
 

extensions/todo.ts

@@ -10,9 +10,9 @@
  * correct for that point in history.
  */
 
-import { StringEnum } from "@mariozechner/pi-ai";
+import { StringEnum } from "@earendil-works/pi-ai";
-import type { ExtensionAPI, ExtensionContext, Theme } from "@mariozechner/pi-coding-agent";
+import type { ExtensionAPI, ExtensionContext, Theme } from "@earendil-works/pi-coding-agent";
-import { matchesKey, Text, truncateToWidth } from "@mariozechner/pi-tui";
+import { matchesKey, Text, truncateToWidth } from "@earendil-works/pi-tui";
 import { Type } from "typebox";
 
 interface Todo {

install.sh

@@ -41,7 +41,7 @@ link_into_repo() {
 require_pi_installed() {
     if [[ ! -d "$PI_AGENT_DIR" ]]; then
         err "pi not detected at $PI_AGENT_DIR"
-        printf '    Install pi first: https://github.com/mariozechner/pi-coding-agent\n'
+        printf '    Install pi first: https://github.com/earendil-works/pi\n'
         printf '    Re-run after `pi --help` (first run creates ~/.pi/agent/).\n'
         exit 4
     fi