Send a follow-up message into a run (retired)

**Retired — always returns `410 Gone`.**

POST /api/v1/runs/{runId}/messages

Retired — always returns 410 Gone.

This forwarded the message into the run’s PTY as if typed. Runs are no longer interactive: they are driven by the Claude CLI in stream-json mode, which reads its prompt once and has no input channel.

The route returns an error rather than being removed because the old behaviour could not fail honestly — delivery was reported against the container’s socket, not against anything that read the message, so a call would have kept returning 202 delivered: true while the message went nowhere.

Use POST /api/v1/flows/{flowId}/chat with a stable sessionId.

Authentication

Requires a project API key — see Authentication.

Parameters

NameInTypeRequiredDescription
runIdpathstringrequiredUUID of the run.

Responses

StatusDescription
410Endpoint retired; use the chat endpoint.

Tag: Interactions