ui-send-message

name	ui-send-message
description	Send a message in the active session of the Claude Code WebUI. Use when typing and sending a message to Claude, submitting a prompt, interacting with an active session, or waiting for the assistant to finish responding.
allowed-tools	["mcp__chrome_devtools__wait_for","mcp__chrome_devtools__click","mcp__chrome_devtools__type_text","mcp__chrome_devtools__press_key","mcp__chrome_devtools__take_snapshot","mcp__chrome_devtools__evaluate_script","mcp__chrome_devtools__take_screenshot"]

ui-send-message

Send a message in the active session and optionally wait for the assistant to finish responding.

Inputs

• message (required) — Text to send
• wait_for_idle (optional, default: true) — Wait for the assistant to finish before returning

Prerequisites

A session must be active and selected. Run ui-navigate with the appropriate project and session arguments first if needed.

Steps

1. Verify Session is Ready

Check that the active session chip exists and is NOT in processing state:

wait_for(selector=".agent-chip.active", timeout=5000)

Check the input area is enabled. Wait for the textarea to not be disabled:

wait_for(selector="#message-input:not([disabled])", timeout=10000)

If the input is still disabled after 10s: take a snapshot and report "Input area is disabled. Session may be processing, disconnected, or starting."

2. Click the Input Area

click(selector="#message-input")

3. Type the Message

Use type_text to enter the message content. This appends to whatever is in the field:

type_text(text=<message>)

If the input needs to be cleared first, use evaluate_script:

const input = document.querySelector('#message-input');
input.value = '';
input.dispatchEvent(new Event('input', { bubbles: true }));

4. Send the Message

Press Enter to send (preferred method — matches normal user behavior):

press_key(key="Enter")

Alternative: click the Send button:

click(selector=".input-container .btn.btn-primary")

Note: The Send button shows text "Send" when idle, and is replaced by "Stop" when processing. Only click the Send button if it shows "Send" text.

5. Wait for Processing to Start

After sending, wait briefly for the session to enter processing state (purple dot):

wait_for(selector=".agent-chip.active .ac-status-sq.active-processing", timeout=5000)

If the processing indicator never appears within 5s, the message may have been sent to a queued session or the session started very fast. Continue to the idle check regardless.

6. Wait for Idle (if wait_for_idle is true)

Poll for the session to return to idle state (green dot, not processing). Do NOT use a fixed sleep.

wait_for(selector=".agent-chip.active .ac-status-sq.active:not(.active-processing)", timeout=120000)

Wait up to 120 seconds for the assistant to finish. If timeout: take a screenshot, take a snapshot, and report "Session did not return to idle within 120s. May still be processing. Check for permission prompts (.ac-alert.permission)."

Permission detection during wait: If the session enters .paused state while waiting:

// Check for paused state (amber dot)
.agent-chip.active .ac-status-sq.paused
// or permission alert badge
.agent-chip.active .ac-alert.permission

If paused, report "Session is paused awaiting permission. Use ui-permission-respond to handle the permission request before continuing."

7. Confirm Response Received

Take a snapshot to verify a response appeared in the message area:

wait_for(selector=".messages-area", timeout=5000)

Use evaluate_script to check the last message:

const msgs = document.querySelectorAll('.messages-area .message-item');
const last = msgs[msgs.length - 1];
last?.textContent?.trim().substring(0, 100)

Idle State Detection

The session is idle (ready for next message) when:

• .agent-chip.active .ac-status-sq.active exists (green dot)
• AND .agent-chip.active .ac-status-sq.active-processing does NOT exist

Use evaluate_script for explicit check:

const chip = document.querySelector('.agent-chip.active');
const sq = chip?.querySelector('.ac-status-sq');
sq?.classList.contains('active') && !sq?.classList.contains('active-processing')

Error Handling

• Input disabled: Session may be in starting or terminating state. Wait or run ui-navigate to select a valid active session.
• Message not sent: Verify #message-input received the text. Check for validation errors.
• Session stuck in processing: After 120s take a screenshot. Check for permission modal in the activity timeline.
• Permission required: Pause and invoke ui-permission-respond with appropriate action.

Queue vs Send

If the session is processing when you call this skill and you want to queue the message rather than wait:

• Click the "Queue" button (.btn.btn-info with text "Queue") instead of Send
• Queued messages are delivered automatically when the session returns to idle