adk web: asterisks in user messages rendered as Markdown italic instead of literal text

[Subhamkp]

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triaging. Requests without complete information may be rejected / deprioritized.
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Describe the Bug:
The adk web chat UI interprets asterisk (*) characters in user messages as Markdown italic formatting instead of displaying them as literal text. Math expressions like 2*3*4*5 are rendered as 234*5 in the chat bubble.

Steps to Reproduce:

1. Create any ADK agent
2. Run adk web
3. Open http://localhost:8000 and select the agent
4. Type 2*3*4*5 in the chat input and send
5. Observe the user message bubble renders as 234*5

Expected Behavior:
The user message bubble should display the literal text 2*3*4*5 exactly as typed.

Observed Behavior:
The asterisks are consumed as Markdown italic markers. 2*3*4*5 becomes 2 + 3 (italic) + 4 + 5 → displays as 234*5. The agent receives the correct input (verified in the event panel on the left side), so this is purely a frontend rendering issue.

Environment Details:

• ADK Library Version (pip show google-adk): 1.27.1
• Desktop OS:** macOS
• Python Version (python -V): 3.12

Model Information:

• Are you using LiteLLM: No
• Which model is being used: gemini-2.5-flash

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Regression:
N/A (first time using adk web)

Logs:
N/A — no errors in logs, this is a frontend rendering issue only.

Screenshots / Video:
If applicable, add screenshots or screen recordings to help explain
your problem.

Additional Context:
Add any other context about the problem here.

Minimal Reproduction Code:
Please provide a code snippet or a link to a Gist/repo that isolates the issue.

# Any agent will reproduce this. Minimal example:
from google.adk.agents import LlmAgent

root_agent = LlmAgent(
    model="gemini-2.5-flash",
    name="test_agent",
    instruction="You are a helpful assistant.",
)
# Run: adk web
# Type: 2*3*4*5

How often has this issue occurred?:

• Always (100%)

[sanketpatil06]

Hello @wuliang229 ,
I have verified the Request Trace, and the data looks perfect on the backend—both the Input and Output is exactly what it should be. The problem is definitely in the UI; the Markdown parser is misreading asterisks (*) as a command to make text into Italics instead of just showing the symbol.

Since the actual data is fine, we need to prioritize this UI fix so users don't think their information is being corrupted or displayed incorrectly.

Could you please take a look? Thanks!

Evidence: