Merge main skill installation guidance into debugging branch

crates/bsk-cli/skill/SKILL.md

@@ -20,10 +20,11 @@ advice-only tasks. Never extract credentials, cookies, tokens, or other secrets.
 - If a browser profile is required, read [tabs and profiles](references/tabs-and-profiles.md)
   before starting. Verify its instance mapping, bind every new session explicitly,
   and never substitute another instance or omit the selector to recover.
-- Commands normally auto-start the daemon. If the host cleans up background children,
-  read [environment setup](references/environment.md) before any session command.
-  Also read it for remote pairing or startup failures. Never restart a shared daemon
-  or delete runtime files to recover.
+- Installing this skill does not install the `bsk` CLI or browser extension.
+  For a missing CLI, startup or connection failure, or remote pairing, read
+  [environment setup](references/environment.md). Commands normally auto-start the
+  daemon; if the host cleans up background children, read that guide before any
+  session command. Never restart a shared daemon or delete runtime files to recover.
 - Borrow confirmation and human help follow the extension's Automation settings.
   Never change settings or switch browser backends to bypass them.
 
@@ -115,7 +116,7 @@ A task may need more than one reference as it progresses.
 | --- | --- |
 | Website debugging, reproduction evidence, or request rules/replay | [Debugging](references/debugging.md) |
 | Required profile, existing user tab, multiple/background tabs, or remote tab ownership | [Tabs and profiles](references/tabs-and-profiles.md) |
-| Sandboxed daemon startup, connection failure, or remote pairing | [Environment](references/environment.md) |
+| Missing CLI, daemon startup failure, sandboxed startup, connection failure, or remote pairing | [Environment](references/environment.md) |
 | Hover menus/probing, scrolling, `next_cursor`/`@more`, console/network, emulation, evaluation, or recording | [Interaction details](references/interaction-details.md) |
 | Screenshot, full-page capture, or `[visual:screenshot]`/Canvas interaction | [Screenshots and Canvas](references/screenshots-and-canvas.md) |
 | Upload or download | [Files](references/files.md) |

crates/bsk-cli/skill/references/environment.md

@@ -1,7 +1,21 @@
 # Before starting a session
 
+## CLI availability
+
+If `bsk` is not found, check `PATH` and existing installations before installing it.
+The official installers default to `~/.local/bin` (`bsk.exe` on Windows); check
+`BSK_INSTALL_DIR` for a custom location. Reuse an existing installation by fixing
+`PATH` or using the executable's absolute path. If the CLI is missing, follow the
+[installation guide](https://github.com/Tencent/BrowserSkill/blob/main/AGENT_INSTALL.md)
+on the Agent's machine. After installation or a path fix, verify the executable
+with `bsk --version` (or its absolute path with `--version`).
+
+## Remote connection
+
 For remote setup or pairing, follow the [remote guide](https://github.com/Tencent/BrowserSkill/blob/main/docs/remote-extension-connection.md).
 
+## Local daemon startup
+
 Local commands normally auto-start the daemon. If the host terminates background
 children after each shell call, including on Windows, complete these steps first:
 
@@ -29,3 +43,13 @@ Use the same `BSK_HOME` and `BSK_AUTO_START=0` on EVERY sandboxed command;
 environment settings may not persist between shell calls. Keep browser commands
 sandboxed. For other startup failures, retry once, then use `bsk doctor`.
 A local process identity warning permits browser commands when IPC works.
+
+## Extension connection
+
+If the intended extension is still disconnected after the applicable setup above,
+run `bsk doctor` on the Agent's machine using the same daemon environment and
+follow its failure hints. A disconnected extension does not prove it is missing.
+If installation or browser-side connection steps are needed, direct the user to
+the [extension setup guide](https://github.com/Tencent/BrowserSkill/blob/main/AGENT_INSTALL.md#4-connect-the-browser-extension).
+After setup or repair, rerun `bsk doctor` with the same environment and address
+any remaining `fail` checks before starting a session.