Reference

Errors and limits

HTTP responses, tool errors, rate limits and how to retry safely.

Kinro reports problems in two places: HTTP status codes from the endpoint, before any tool runs, and tool results with isError: true, after a tool has run. In both cases the text says what happened and what to do next.

HTTP responses

Status	Meaning	What to do
`200`	The JSON-RPC message was handled. Check the result for tool errors.	—
`400`	The body is not valid JSON, or it is a JSON-RPC batch. Batches are not supported.	Send one JSON-RPC message per HTTP request.
`403`	The request came from a web page in a browser. Browser origins are not supported.	Call the endpoint from your server or MCP client, not from page scripts.
`405`	The method was not `POST`. The server offers no event stream to `GET`.	Use `POST`.
`413`	The request body is larger than 30 MB.	Send fewer or smaller inline files per message.
`429`	Kinro's MCP endpoint is at capacity.	Wait for the number of seconds in the `Retry-After` header, then retry.
`503`	Kinro's MCP endpoint is temporarily unavailable. No tool ran.	Retry after a short wait.

A 429 or 503 means the request was not processed, so retrying it is safe. Capacity is shared by all callers and measured over rolling windows; access reopens on its own.

Tool errors

Situation	What the result says	What to do
No conversation	There is no conversation with Kinro yet.	Call `ask_kinro` with the user's message and no `conversation_id`, then reuse the ID it returns.
Still answering	Leo is still answering the previous message.	Call `ask_kinro` without a message to get the reply before sending another message.
Completion unknown	Leo's response could not be retrieved, and Kinro cannot confirm whether the message was handled.	Do not resend automatically. Check with `ask_kinro` without a message, then ask the user.
Document refused	Why a file was refused: type, size, encoding, source, or a daily limit. Nothing was sent.	Tell the user. Resend without the file if they want to continue. See Documents.
Paused	Kinro's connection for this app is paused, and the message was not sent.	Tell the user to try again later or contact Kinro at kinro.com.
Check failed	New messages could not be retrieved.	Check again shortly.

Retrying safely

ask_kinro with a message sends it each time it is called. Never retry it automatically, except after an HTTP 429 or 503, which means nothing was sent.
ask_kinro without a message sends nothing, but it delivers new messages once. Keep checks sequential and save their results; a lost response may not be recovered by checking again. See Conversations.
When Kinro says it is still working on your message, the message was received. Check with ask_kinro without a message; do not resend.