MessageParseError on rate_limit_event message type terminates async generator #601
Description
Description
The CLI emits a rate_limit_event message at session start on every run. The SDK's parse_message function does not handle this message type, hitting the catch-all case in its match statement and raising MessageParseError. Since this exception occurs inside the async generator, it terminates the stream and the consumer never receives the ResultMessage with output, cost data, or session ID.
This is not triggered by actually hitting a rate limit. It's an informational status message emitted on 100% of sessions.
Payload
{
"rate_limit_info": {
"isUsingOverage": false,
"overageDisabledReason": "org_level_disabled",
"overageStatus": "rejected"
},
"type": "rate_limit_event",
"uuid": "edf7a929-4317-4642-85e2-3bd9ee2b97b9"
}
Repro
from claude_agent_sdk import query, ClaudeAgentOptions
async for message in query(
prompt="What is 2 + 2?",
options=ClaudeAgentOptions(allowed_tools=["Bash"]),
):
print(message)
Raises MessageParseError before ResultMessage is received.
Environment
claude-agent-sdk==0.1.39- Python 3.14.3
- macOS (Darwin)
- Claude Code CLI in PATH, authenticated via OAuth token
Suggested fix
Handle rate_limit_event in parse_message by either returning a SystemMessage with the payload or silently skipping it. The data is informational and should not terminate the stream.