mcp-demo/skills/kimi-webbridge/SKILL.md

---
name: kimi-webbridge
description: |
  Kimi WebBridge lets AI control the user's real browser — navigate, click, type, read, screenshot, and interact with any website using the user's actual login sessions. Use this skill whenever the user wants to interact with websites, automate browser tasks, scrape web content, or perform any action requiring a real browser. Also use when the user mentions "browser", "webpage", "open URL", "screenshot", or asks to read/interact with any website. Use even for simple-sounding browser requests — the daemon handles all complexity.
metadata:
  version: "1.11.3"
---

# Kimi WebBridge

Control the user's real browser (with their login sessions) via a local daemon at `http://127.0.0.1:10086`.

## Tools

| Tool | Args | Returns | Note |
|------|------|---------|------|
| `navigate` | `url`, `newTab`(bool), `group_title` | `{success, url, tabId}` | First call opens a tab — see [Tabs](#tabs-and-the-current-tab). `group_title` sets the group's visible label |
| `find_tab` | `url`, `active`(bool) | `{success, url, tabId, borrowed}` | Re-select a tab **this session** opened; `active:true` borrows the tab the **user** is viewing — see [Tabs](#tabs-and-the-current-tab) |
| `snapshot` | — | `{url, title, tree}` with `@e` refs | **Accessibility tree** (text) — use this to read page content and locate elements |
| `click` | `selector` (@e ref or CSS) | `{success, tag, text}` | Synthetic `el.click()` |
| `fill` | `selector`, `value` | `{success, tag, mode}` | Works on `<input>`/`<textarea>` AND `[contenteditable]` (ProseMirror/Lexical/Slate). `mode` is `"value"` or `"contenteditable"` |
| `evaluate` | `code` (supports async/await) | `{type, value}` | |
| `cdp` | `method`, `params` | raw CDP response | Raw `chrome.debugger` passthrough — what `evaluate` is to JS, `cdp` is to CDP. Low-level escape hatch for cases the tools above don't cover |
| `screenshot` | `format`(png\|jpeg), `quality`(0-100), optional `selector` (@e/CSS), optional `path` | `{format, path, sizeBytes, mimeType}` | Returns a file path, not base64 — see [Screenshots](#screenshots) |
| `network` | `cmd`(start\|stop\|list\|detail), `filter`, `requestId` | request/response data | |
| `upload` | `selector`, `files`(string[]) | `{success, fileCount}` | |
| `save_as_pdf` | `paper_format`, `landscape`, `scale`, `print_background`, optional `path` | `{path, sizeBytes, mimeType, pageTitle}` | Render current page → PDF, returns a file path — see [Save as PDF](#save-the-current-page-as-pdf) |
| `list_tabs` | — | `{success, tabs:[{tabId, url, title, active, groupTitle}]}` | Inspect tabs in the current session |
| `close_tab` | — | `{success, closed: bool}` | Close the current tab in the session |
| `close_session` | — | `{success, closed: int}` | Close all tabs in the session — `closed` is the count. See [Sessions](#sessions) for when to call |

### Tabs and the current tab

Single-tab tools (`snapshot`, `click`, `fill`, `screenshot`, `save_as_pdf`) act on the **current tab** — the one you most recently opened with `navigate` or selected with `find_tab`.

- **Opening pages**: use `newTab:true` when pages should coexist (comparing, cross-referencing); omit it to send the current tab to a new URL.
- **Going back to an earlier tab**: call `find_tab` to make a tab **you opened earlier in this session** the current one again. Pass the tab's **full URL** — take it from `list_tabs` or the earlier `navigate` result. A bare root domain (`kimi.com`) may miss a `www.kimi.com` tab, so prefer the exact URL. By default `find_tab` searches **only this session's own tabs** — it never reaches into the user's other tabs or windows.
- **Acting on a page the user already has open**: pass `active:true` ("use my open X tab" / "the X page I'm viewing"). It **borrows** the tab the user is currently viewing (returns `borrowed:true`); the borrowed tab is operated in place — it is not pulled into the session's tab group.
- If `find_tab` errors with "no tab matching … in this session", the page isn't open in this session — `navigate` with `newTab:true` instead.

```bash
curl -s -X POST http://127.0.0.1:10086/command \
  -d '{"action":"find_tab","args":{"url":"https://www.kimi.com","active":true},"session":"k26-research"}'
```

### Call Format

Every command carries a top-level `session` naming the current task — see [Sessions](#sessions) below. The examples in later sections omit it only for brevity; in real calls always include it. The command format depends on the user's OS.

**macOS / Linux** — inline JSON is fine:

```bash
curl -s -X POST http://127.0.0.1:10086/command \
  -H 'Content-Type: application/json' \
  -d '{"action":"navigate","args":{"url":"https://example.com","newTab":true,"group_title":"My task"},"session":"my-task"}'
```

**Windows (PowerShell / cmd)** — the shell corrupts non-ASCII characters (Chinese etc.) carried inline in command arguments or pipes; they reach the daemon as `?` and the text is unrecoverable. Send **every** request as a file body instead:

1. Write the JSON body to a **uniquely-named** temp file with your own file-write tool — never with shell `echo`/heredoc, which corrupts non-ASCII the same way. Give **every** request its own filename with a random suffix (e.g. `webbridge-req-<random>.json`) so concurrent requests never share a file and overwrite each other.
2. POST the file with `curl.exe` — always `curl.exe`, never bare `curl`, which Windows PowerShell aliases to `Invoke-WebRequest`:

```powershell
curl.exe -s -X POST http://127.0.0.1:10086/command -H "Content-Type: application/json" --data-binary "@$env:TEMP\webbridge-req-<random>.json"
```

3. Delete the temp file as soon as the request returns — don't leave request bodies on disk.

## Sessions

**One task = one session = one tab group.** A `session` collects every tab the task opens into one tab group, so the user sees a single group for "what the agent is doing right now". Pass it as a **top-level field** of the request body (not inside `args`).

- **Pick one session name at the task's start, put it on every command, and never switch mid-task — even across different sites.** Switching session names per site is the #1 cause of fragmented tab groups.
- Name it after the **task**, not the site (`camping-research`, `phone-compare`). Use multiple sessions only for genuinely unrelated parallel tasks.
- `group_title` is the human-readable group label — write it in the user's language, on the **first** `navigate` of the task.
- When you create the group (the first `navigate` of a task), tell the user once that this task's pages are collected under group «title», and that you'll close them whenever they ask.

```bash
# First tab: set session + a human label (in the user's language)
curl -s -X POST http://127.0.0.1:10086/command \
  -d '{"action":"navigate","args":{"url":"https://www.kimi.com","newTab":true,"group_title":"K2.6 feature research"},"session":"k26-research"}'
# Another site, same task → same session → joins the same group automatically
curl -s -X POST http://127.0.0.1:10086/command \
  -d '{"action":"navigate","args":{"url":"https://www.moonshot.cn","newTab":true},"session":"k26-research"}'
```

Closing is always user-initiated: call `close_session` only when the user explicitly asks ("close those", "clear the tabs"). It clears the whole group in one call.

## Screenshots

The daemon writes the image to disk and returns `{format, path, sizeBytes, mimeType}` — never base64, since the model can't read raw image bytes. Take the `.path` and open it with the `Read` tool to actually see it.

```bash
# Default: PNG of the visible viewport, daemon picks a temp path
curl ... -d '{"action":"screenshot","args":{}}'
# Options (each independent): JPEG quality, element-only via @e/CSS selector, custom output path
curl ... -d '{"action":"screenshot","args":{"format":"jpeg","quality":60}}'
curl ... -d '{"action":"screenshot","args":{"selector":"@e123"}}'
```

A caller-supplied `path` is honored verbatim (parent dirs created, existing file overwritten) — use a unique name to avoid clobbering. `save_as_pdf` follows the same rule.

## Prefer snapshot over CSS/JS selectors

`snapshot` returns interactive elements with `@e` refs based on semantic role/name. Use them directly with click/fill — they survive CSS class hash changes that break manually-written selectors.

Fall back to `evaluate` (JS) only when:
- The target has no `@e` ref in the snapshot
- You need attributes not in the snapshot (e.g., `href`)
- You need to dispatch complex event sequences, or scroll

## Evaluate Tips

- Always use compact `JSON.stringify(data)` — never add `null, 2` formatting. Indentation and newlines can inflate the response several times over, causing truncation during transmission.
- `evaluate` calls share the page's JS realm — re-declaring the same `const`/`let` across two calls throws `SyntaxError`. Wrap in an IIFE for a fresh scope: `(() => { const x = ...; return x; })()`.

## Text input — use `fill`

`fill` (selector = CSS or `@e` ref, plus the value) works on `<input>`/`<textarea>` (returns `mode: "value"`) and on `[contenteditable]` rich editors — ProseMirror, TipTap, Lexical, Slate, Quill, etc. (returns `mode: "contenteditable"`), firing the right input events so the page reacts.

`fill` is **clear-and-insert**: existing content is replaced. To append, read the current value via `evaluate`, concatenate, then `fill` with the result.

## Form submit / special keys

There's no separate "press Enter" tool. To submit a form, click the submit button directly (`click` on the @e ref or selector). To dispatch a key event programmatically (e.g. Escape to close a modal):

```bash
{"action":"evaluate","args":{"code":"document.activeElement.dispatchEvent(new KeyboardEvent('keydown',{key:'Escape',bubbles:true}))"}}
```

## Save the current page as PDF

`save_as_pdf` renders the current page to PDF and returns the file path. All args optional:
- `paper_format`: `letter` (default) \| `a4` \| `legal` \| `a3` \| `tabloid`
- `landscape`: `false` (default)
- `scale`: `1.0` (default), range `[0.1, 2.0]`
- `print_background`: `true` (default) — keep background colors
- `path`: caller-supplied output path; if absent, daemon picks a default under OS temp dir using the page title as the filename

`path` semantics match `screenshot`: written verbatim, parent dirs auto-created, existing files overwritten.

Decoded PDF cap is 100 MB. Above that the daemon refuses; reduce `scale` or split the page.

## Known limitations

- **Sites that strictly check `event.isTrusted`** (some banking portals, captchas) ignore `click` / `fill` because those fire DOM-level synthetic events (`isTrusted=false`). For these, tell the user the page needs manual interaction. (Trusted input is possible at the protocol level via the `cdp` escape hatch, but treat that as advanced.)
- **Cross-origin iframes**: `fill`, `click`, `evaluate`, and `snapshot` operate on the top frame. If a target element lives in a same-page iframe from a different origin (e.g. embedded sandbox demos), navigate to the iframe's URL directly instead.

## If a tool call fails (daemon or extension not ready)

**If a tool call can't reach the daemon (connection refused), start it yourself — don't ask the user. This is safe to run anytime: it no-ops if the daemon is already up.**

**macOS / Linux:**

```bash
~/.kimi-webbridge/bin/kimi-webbridge start
```

**Windows (PowerShell):**

```powershell
& "$env:USERPROFILE\.kimi-webbridge\bin\kimi-webbridge.exe" start
```

Then retry the tool call. If it still fails — or the browser extension won't connect — point the user to the help page instead of deep-troubleshooting:

- English: https://www.kimi.com/features/webbridge
- 中文: https://www.kimi.com/zh-cn/features/webbridge

Never run `stop` / `restart` / `uninstall` automatically — those kill a running daemon. See `references/operations.md` for anything deeper.

## Version mismatches

If a tool returns an error containing **"Please update the Kimi WebBridge extension"**, the user's browser extension is older than this skill. Don't try to reconcile versions yourself — just tell the user, in their language, to update the extension and retry:

- English: https://www.kimi.com/features/webbridge
- 中文: https://www.kimi.com/zh-cn/features/webbridge