Kimi Webbridge

Kimi WebBridge

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

Health check (always do this first)

~/.kimi-webbridge/bin/kimi-webbridge status

Then act on the result:

• `running: true` and `extension_connected: true` — healthy. Proceed with the tool calls below.
• Anything else (command not found, running: false, extension_connected: false, errors) — Read `references/operations.md` in this skill directory. It has the install / start / diagnose routing table.

Don't guess fixes here — every non-healthy state is handled in references/operations.md.

Tools

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 already opened the current one again. Pass the tab's full URL — take it from list_tabs or the earlier navigate result. A bare root domain (zhihu.com) may miss a www.zhihu.com tab, so prefer the exact URL. active:true picks the tab the user is currently viewing — use it when they say "用我打开的 X" / "在我当前的 X 页面上"; otherwise the leftmost match wins.
• If find_tab returns "no open tab found", the page isn't open — navigate with newTab:true instead.

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

Call Format

Every command carries a top-level session naming the current task — see Sessions below. The examples in later sections omit it only for brevity; in real calls always include it.

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"}'

Sessions

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

Rules:

1. Pick one session name when the task starts, put it on _every_ command, and never change it mid-task. 2. One task uses one session — even across multiple sites. Searching on Google and then opening results on three different domains all share the same session and land in the same group. Do not switch session names per site — that is the #1 cause of fragmented tab groups. 3. Name the session after the task, not the site or domain — e.g. camping-research, phone-compare. 4. group_title is the human-readable label shown on the group in the browser. Write it in the user's language (match the conversation — Chinese or English). Pass it on the first navigate; later calls in the same session don't need it. 5. Use multiple sessions only when the user asks for several unrelated tasks at once — one session per task.

# First tab of the task: set session + human-readable label (in the user's language)
curl -s -X POST http://127.0.0.1:10086/command \
  -d '{"action":"navigate","args":{"url":"https://www.google.com/search?q=tents","newTab":true,"group_title":"Camping gear research"},"session":"camping-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.zhihu.com/search?q=tents","newTab":true},"session":"camping-research"}'

# Every later command carries the same session
curl -s -X POST http://127.0.0.1:10086/command \
  -d '{"action":"snapshot","args":{},"session":"camping-research"}'

When the task is finished and the user no longer needs these pages, close_session clears the whole group. If they might want to look further (a follow-up question, inspecting a result), deliver your answer first and leave the tabs open — closing too eagerly throws away the work the user can still see.

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.

# 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 handles all three text input shapes. Pass selector (CSS or @e ref) + value:

fill is clear-and-insert: existing content is replaced. For "append to existing text", 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):

{"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, captcha challenges) reject fill and click because both go through DOM-level synthetic events (isTrusted=false). This is a product boundary, not a bug — no automation primitive that runs on the user's machine without stealing OS focus can produce trusted events on these sites.
• 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.

Versions

Daemon, extension, and this skill share a 1:1 version string. Read both via:

~/.kimi-webbridge/bin/kimi-webbridge status
# {"version":"<daemon>", "extension_version":"<extension>"}

If a tool returns an error containing "Please update the Kimi WebBridge extension", the user's extension is older than this skill. Tell the user:

请更新 Kimi WebBridge 浏览器扩展后重试：https://kimi.com/features/webbridge

Don't retry the failed tool. Don't auto-switch skill versions based on extension_version — the pairing protocol isn't finalized.

Operations: install, lifecycle, diagnose

Read this file when the health check in SKILL.md indicates the daemon is missing, not running, or the extension isn't connected — or when the user explicitly asks to install, start, stop, restart, or troubleshoot kimi-webbridge.

Path convention

The kimi-webbridge binary always lives at ~/.kimi-webbridge/bin/kimi-webbridge, regardless of how it was installed. Status, PID, and logs live under ~/.kimi-webbridge/.

Routing table (what to do based on status)

Run: ~/.kimi-webbridge/bin/kimi-webbridge status

/status JSON fields

• running (bool) — daemon listening on :10086
• port (int) — 10086
• version (string) — daemon build version
• extension_connected (bool) — a WebSocket client is attached
• extension_id (string) — the Chrome/Edge extension ID, empty if none
• uptime_seconds (int)

Daily operations

• Check status: ~/.kimi-webbridge/bin/kimi-webbridge status
• Start: ~/.kimi-webbridge/bin/kimi-webbridge start (idempotent — safe to call when already running)
• Stop: ~/.kimi-webbridge/bin/kimi-webbridge stop
• Restart after unexpected state: ~/.kimi-webbridge/bin/kimi-webbridge restart
• View recent logs: ~/.kimi-webbridge/bin/kimi-webbridge logs -n 100
• Follow logs live: ~/.kimi-webbridge/bin/kimi-webbridge logs -f
• View previous run's logs: ~/.kimi-webbridge/bin/kimi-webbridge logs --prev

Install flags (install.sh)

When running install.sh:

• Default: install binary + start daemon + install skills to all detected AI agents
• --no-start: install binary + skills, but don't start the daemon
• --no-skill: install binary + start daemon, but skip skill installation
• -h or --help: show usage

Diagnosing common failures