Literal search accepts one-character queries only for live session

What version of Kimi Code is running?

0.39.0

Which open platform/subscription were you using?

Developer / Open Source

Which model were you using?

kimi-for-coding

What platform is your computer?

Linux 6.1.102 x86_64 x86_64

What issue are you seeing?

Literal search (
) behaves inconsistently between live and indexed sessions. A one-character normalized Unicode query (e.g., "苹") is accepted and returns hits when a live session is active (
container.sessionId
points to a live transcript), but the exact same query is rejected with an
invalid_query
error when routed to the search index.

What steps can reproduce the bug?

Reproduction payload:
{
"query": "苹",
"mode": "literal",
"container": { "sessionId": "" }
}

Error message (when not live):

literal queries need at least 2 characters (after Unicode normalization)
(Error code: 40001)
The validation should be centralized to ensure consistent behavior regardless of the session's liveness state.

What is the expected behavior?

Error message (when not live):

literal queries need at least 2 characters (after Unicode normalization)
(Error code: 40001)
The validation should be centralized to ensure consistent behavior regardless of the session's liveness state.

Additional information

No response

Contribution

• I am willing to submit a PR for this bug fix myself (please wait for maintainer approval in this issue first)

Trace literal-query validation for requests with a live container.sessionId and requests routed to the search index, starting from the path that emits invalid_query 40001. Compare the Unicode-normalized length checks and centralize the validation so both paths have consistent behavior, then add or run tests covering the one-character query "苹" in live and indexed sessions.